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THE NEW GEOGRAPHY DICTIONARY KEY GEOGRAPHICAL TERMS FOR THE 21ST CENTURY

J e ff H a r t e


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Copyright © 2003 Geography Teachers’ Association of New South Wales Inc. All rights reserved. No reproduction, copy or transmission of this publication may be made without written permission No paragraph or section of this publication may be reproduced, copied or transmitted save with written permission or in accordance with the provisions of the Copyright Act of 1996 (as amended) Copying for educational purposes Where copies of part or whole of this book are made under Part VB of the Copyright Act, the law requires that prescribed procedures be followed. For information, contact the Copyright Agency Limited. Acknowledgments The author and publisher wish to thank • Nyree Malone for carefully crafting all diagrams and line drawings • Nick Hutchinson, President of the Geography Teachers’ Association of New South Wales, for his initial and ongoing support of this project as well as Geoff Paterson for his meticulous editing • Figure 62 – reproduced with permission Geoscience Australia • Figures 63, 67 and 69 – source ©Land and Property Information, Panorama Avenue, Bathurst 2795 www.lpi.nsw.gov.au • Figure 64 – reproduced with permission of the Department of Defence, Australia • Figure 65b – reproduced with permission Geography Teachers’ Association of NSW (P Skinner and A Mahler) • Figure 68 – base map reproduced with permission of TASMAP *** Every effort has been made to trace and acknowledge copyright material. The author and publisher would welcome any information from people who believe they own copyright to material in this dictionary. Additional copies of this dictionary can be obtained by contacting: GTANSW c/- Gladesville Public School PO Box 602 Gladesville NSW 1675 National Library of Australia Cataloguing-in-Publication data The New Geography Dictionary – Key Geographical Terms for the 21st Century ISBN 0 9751105 0 0 1. Geography Dictionary 2. Key Terms in Geography Cover, text layout, design and typesetting by: Imagine Success, Paradise Point, Queensland 4216 — imagine@jaywey.com Printed by: Fergies the Printers, Brisbane Published by: Geography Teachers’ Association of New South Wales Inc.

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PREFACE Author’s Note Initially conceived as a much smaller project, this Dictionary is the result of a perceived need for Geography students to improve their use of appropriate Geographic terminology, their comprehension, and overall Geographic literacy. There is a variety of excellent Geography textbooks for students, many of which provide key-word glossaries. There is, however, no central source for students to access the necessary terminology. As a result, a much larger volume has evolved. The key terms included here, and necessary to succeed in Geography, address the themes of ‘environments’, ‘communities’ and ‘changing environments and communities’. Within these themes a major focus has been given to terms relating to the atmosphere, lithosphere, hydrosphere, biosphere and the human environment. Although there is a range of dictionaries available to students, there is no dictionary that currently meets the needs of Australia’s young Geographers. There are dictionaries on areas such as ‘the environment’, ‘the ecosystem’, ‘Human Geography’ and ‘Physical Geography’ – but none that address the vocabulary needed to succeed in the learning sphere of most concern to students. Students need to grapple with the intricacies of the biophysical environment, population and settlement, development, globalisation and even geopolitics as stipulated by the various syllabuses throughout Australia and around the world. The entries in The New Geography Dictionary are necessarily brief but they can be enhanced with reference to supporting italicised terms. Sufficient detail is provided to meet the needs of most Geography students. A variety of approaches has been included beyond straight definitions – these include tabular summaries such as in ‘contemporary geographic issues’ and the ‘geologic timescale’, illustrative summaries such as in coastal terrains and the general circulation of the atmosphere, as well as tables, photographs and graphs. Many entries make reference to illustrative material. This material has been included because the author acknowledge that students absorb and comprehend material in different ways. Sketch-diagrams, tables and photographs add to an enhanced understanding of the terms addressed. Some this illustrative material is provided in full colour. These items are referred to in the text and can be located in the full colour sections of this dictionary. Students using this Dictionary will find the key terms are highlighted in bold followed by a concise definition. Many definitions include specialist terms and have their own family of related concepts. For example, the ‘family’ of terms associated with ‘dune’ include: seif dune, barchan dune, frontal dunes, and foredunes. Readers are referred elsewhere in the Dictionary for an explanation of these related terms with the term italicised. Also included at the end of this Dictionary are some standard abbreviations, prefixes and conversions that students will find useful.

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‘Populations of all countries of the world’ are also included with comparisons made between 1999 figures and projected 2050 figures. While the terms included in this Dictionary are those most Geography students will encounter in their studies they are by no means exhaustive. For more detailed explanations and a broader, academic, treatment of Geographic terminology readers are referred to M. Allaby’s Dictionary of the Environment, A. Goudie’s Encyclopedic Dictionary of Physical Geography and R. Johnston’s Encyclopedic Dictionary of Human Geography. Syllabuses throughout Australia are increasingly focusing on not only developing key competencies (skills), but also providing students with the opportunities to apply these skills. Not just map, graph and statistical skills but also skills that develop effective communication – both oral and written. These include encouraging and enhancing students’ literacy skills. In this way students can be more effective agents of change, and contribute positively to community understanding. This relevant and up-to-date dictionary provides students with the necessary tools to be effective Geographers and to better understand and participate in the world around them. Improving literacy is increasingly a driving force in education today. Being familiar with subject-specific terminology and using it correctly and in the right context is a major challenge for today’s students. It is hoped that this Dictionary will go some way in meeting this challenge. Jeff Harte Moriah College, 2002

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LIST OF FIGURES 1 Adiabatic lapse rates 2 The vertical structure of the atmosphere 3 Banksia serrata 4 Stages in the development of successive parallel dunes 5 Beaufort scale 6 Bedding planes and vertical joints 7 Biological Oxygen Demand for various organic pollutants 8 Looking up to the canopy 9 The carbon cycle 10 The four, eight and sixteen point compass 11 Inland and coastal catchment areas 12 Techniques for determining climate change 13 Common types of clouds 14 A coastal terrain 15 A woodland – a type of vegetation community 16 Contemporary geographic issues 17 Plate tectonics and continental drift 18 Examples of correlation 19 The Nile delta 20 An arid terrain 21 A dissected plateau – the Shoalhaven River, 22 Examples of drainage patterns 23 El Niño / Southern Oscillation (the ENSO cycle) 24 Faecal coliform counts for selected rivers and lakes 25 A fluvial terrain 26 The general circulation of the atmosphere 27 Geologic time scale 28 A glacial terrain 29 A snow covered glacial valley 30 The greenhouse effect 31 Honeycomb weathering 32 The hydrologic cycle 33 Interlocking spurs 34 The distribution of island-arcs in the Pacific Basin and a cross section across an island-arc 35 Kata Tjuta 36 Climate and lake levels at Willandra

Lakes, New South Wales 37 Latitude and longitude 38 Lianas in a rainforest 39 Cross section (A) and a plan view (B) of the Lake Mungo Lunette, Willandra Lakes, NSW, Aust. 40 Map references 41 Misfit streams 42 The monsoon 43 Open-cut mining in Western Australia 44 The Pacific Ring of Fire – the distribution of earthquakes and volcanoes 45 Petroglyph 46 The Phosphorus Cycle: flows between sources and sinks, Australia-wide 47 Pleistocene sea level changes 48 World population growth 49 Examples of population pyramids 50 Types of precipitation – orographic, frontal and convectional rainfall 51 Types of shore platforms 52 A shore platform 53 A soil profile 54 A speleothem – a limestone column 55 Example of a synoptic chart 56 The tombolo of Palm Beach, NSW 57 Examples of urban hierarchies 58 Urban models of the internal structure of cities 59 The von Thünen landuse model 60 A wetland 61 A zetaform beach 62 Satellite Image – Cairns, Qld 63 Vertical aerial photograph – Port Kembla, NSW 64 Topographic map – Jim Jim Creek, Northern Territory. 65 a) Ground-level photograph, The Pinnacles, W.A. b) oblique aerial photograph, Barrenjoey Headland, NSW 66 Satellite image – Sydney, NSW 67 Vertical aerial photograph – Coffs Harbour, NSW 68 Topographic map – Mersey, Tasmania 69 Orthophotomap – Morpeth, NSW

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ABBREVIATIONS USED < > = % â&#x2C6;&#x17E; asl. APEC

less than greater than equal to percent infinity above sealevel Asia Pacific Economic Cooperation BOD Biological Oxygen Demand BP Before Present CBD Central Business District CFC chlorofluorocarbon CGI contemporary geographic issue cm centimetre CSIRO Commonwealth Scientific and Industrial Research Organisation DO Dissolved Oxygen eg for example ELR environmental lapse rate ENE east north east ENSO El Nino Southern Oscillation ESE east southeast GDP Gross Domestic Product GL gigalitre gm grams GPS Global Positioning System hPa hectopascal HYV high yielding variety ie that is Is. Isle (island) IPCC Intergovernmental Panel on Climate Change kg kilogram kl kilolitre km kilometre square kilometre km2 cubic kilometre km3 (Figure 26 ) (see figure 26 ) (figure 26 colour)

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Lat. Long. L m m2 m3 mg ML mm Mt mya NGO NNE NNW OPEC pop. R. sq. km sq. m SSE SSW SW UN UNCED UNESCO UNEP UNHCR USSR WNW WSW WTO

latitude longitude litre metres square metre cubic metre milligrams megalitre millimetres mount million years ago non-government organisation north northeast north northwest Organisation of Petroleum Exporting Countries population river square kilometre square metre south southeast south southwest southwest United Nations United Nations Conference on Environment and Development United Nations Educational, Scientific and Cultural Organisation United Nations Environment Program United Nations High Commission for Refugees (former) Union of Soviet Socialist Republics west northwest west southwest World Trade Organisation

figure directly related to this entry figure includes this entry figure in colour section


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new geography dictionary geography dictionary new dictionary new geography

A

aa — a blocky, angular form of lava flow abiotic — a term used to refer to those non-living parts of the biophysical environment (see biotic and ecosystem) ablation — the removal of the surface layer of ice due to melting and evaporation. It also refers to the removal of loose material from the land by wind (see deflation) aborigine — an indigenous person of an area eg the Inuit in Alaska and northern Canada; the Koori in Australia abrasion — the wearing down or wearing away by friction. The rubbing of particles on the Earth’s surface, when transported by water or wind, wears away or abrades the surface that these particles come into contact with – such as a sea cliff absolute humidity — the actual amount of water in the air usually expressed as grams (of water) per cubic metre (of air) absolute location — the specific location of a point such as its latitude and longitude, grid reference or area reference (see relative location) absolute zero — theoretically the lowest temperature that can be achieved; that is 0ºK (Kelvin) or -273ºC. Absolute zero indicates the absence of heat and by definition all motion abyssal plain — the flat, sediment covered, sea floor at depths of up to 2–3 kilometres acacia — a type (genus) of tree found in drier subtropical and temperate areas. Acacias are common in Australia in the drier interior of the continent but also in more moist areas where drier microclimates are common such as the

dry exposed areas of plateaus. Acacias are more widely known as Wattles accelerated soil erosion — erosion, beyond that of natural erosion, caused by the activities of people (eg gully erosion, sheet erosion) acclimatisation — adaption by the body to different climatic conditions such as high and low temperatures and high altitude acculturation — the process in which immigrants/indigenous people adopt some of the cultural traits of the dominant culture accumulation — the main aim of capitalism, where capital is reproduced in a ever increasing circle through reinvestment of surplus value or profit acidic rock — an igneous rock containing more than 10% quartz acidity — a term to describe the pH of a soil or water; a pH below 7.2 indicates acidic conditions (see acid soil and pH) acid rain — rainfall with a pH of less than 5.6. This is the pH level in precipitation under natural conditions. Acid rain, or acid precipitation, occurs as a result of the addition of particular chemicals into the atmosphere, such as sulphur and nitrogen oxides. These chemicals are released into the atmosphere as a result of the burning and combustion of fossil fuels. Mixed with water vapour in the atmosphere weak sulphuric and nitric acids are produced with precipitation then having a pH below 5.6. The significance of this is that water received on Earth, such as in lakes, is harmful to fish. Received on land acid rain affects the The New Geography Dictionary

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ability of plants to photosynthesise. Also the weak acid attacks and dissolves any carbonate cements used in building construction (see carbonation) acid soil — a soil that has a pH below 7.2 acid sulphate soils — soils rich in acid sulphide found in tropical and subtropical regions. They are relatively stable under a cover of water but the sulphide forms sulphate and sulphuric acid when they are drained adiabatic — a term used to describe the process where a parcel of air rises, heats up or cools with no gain or loss of heat to the surrounding atmosphere (see adiabatic lapse rate) adiabatic lapse rate — the change in temperature with height as a parcel of air is forced to rise (Figure 1). When air is forced to rise by convection, frontal uplift or by orographic uplift the air rises into an area of lower pressure. The air then expands. As it expands the heat energy within it has to heat a larger volume. So the overall temperature falls. This is adiabatic cooling. Air cools at an adiabatic lapse rate. However two rates apply. If air is

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forced to rise but water vapour within it does not condense the air simply rises, expands (because it rises into an area of lower density) and cools at a rate of 10°C per kilometre. This is called the Dry Adiabatic Lapse Rate. However if, when the air rises, it cools sufficiently so that condensation does occur the air then cools at a different rate. Latent heat is released as a result of condensation; the air is then warmed and so cools at a slower rate of 5.5°C per kilometre. This is called the Moist (or wet) Adiabatic Lapse Rate. As air descends through the tropopause air warms and the reverse process occurs (see subtropical high pressure cell) adobe — bricks made from sun-dried earth or clay. A lot of houses in villages of the developing world have been built using adobe because other materials are not available or are far too expensive advection fog — low cloud or fog produced as a result of warm, moist air moving over cold land. For example when warm, humid air moves onto the land from the sea, the lower levels of the atmosphere are cooled by

Figure 1 – Adiabatic Lapse Rates

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contact with the ground. The air soon reaches dew point and condensation occurs with a low fog blanketing the land. The fog is commonly 1–10 metres deep but can be over 100 metres deep when blanketing a city. Advection fogs roll over coastal areas especially in winter when the ground is very cold aeolian — relating to the wind. For example aeolian landforms such a sand dunes or aeolian processes such as wind erosion aerial photograph — a photograph taken from the air (eg a vertical aerial photograph) at heights such as 1000 metres, 5000 metres etc (see figures 63 and 67 colour) aerial photography — photography taken at a high altitude. Typically these photographs are taken from planes. Where photographs are taken vertically above the ground (eg at 3000 metres) these are called vertical aerial photographs aerial roots — a type of plant root that does not usually grow in the ground but absorbs moisture from the air aerobic — a term to describe conditions that exist in the presence of oxygen. An aerobic environment is one in which oxygen is available for life (see anaerobic) aerological diagram — a graph on which the slope of parts of temperature and moisture profiles that have been recorded by a radiosonde can be read and interpreted. In this way the relative stability/instability of the atmosphere can be determined aerosol — a particle in the atmosphere, for example a dust particle or pollen. The brown haze, especially over cities, and clouds are the result of the accumulation of aerosols in the atmosphere. Aerosols find their way into the atmosphere as a result of volcanic eruptions and dust storms in arid and semi-arid areas. The activities of people also add aerosols to the atmosphere as a result of land clearing

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as well as the pollutants from industrial activity and the burning of fossil fuels such as in cars. These aerosols also act as condensation nuclei in the atmosphere aestivation — see Estivation ageing population — a population where the average age of the population increases over time. For example if 10% of the population is over 55 years of age this year and in 10 years time 15% is over 55, then this is an ageing population (see old population) agglomeration — a term used when various types of activity concentrate in one area. An example of agglomeration is firms concentrating in an area and quite often they do so because they either specialise in a similar type of economic activity or are taking advantage of what other businesses have to offer agglomeration economy — an advantage received from agglomeration. For example firms may concentrate in one area and receive reduced transport rates, cheaper power or reduced land tax. In this sense an economy is an advantage or benefit. Economies of agglomeration often mean reduced costs that may be seen as reduced prices to customers aggradation — the building up of the land by various processes such as deposition and mountain building. Aggradation can occur as the result of the deposition of sediment in a stream or by the wind to form a sand dune or a glacier forming a moraine (see degradation) aggrade — to build up (see aggradation) agistment — the grazing of animals, such as cattle, on someone else’s land for payment. This is done, for example, in times of drought when one farmer pays another farmer to use their land as a source of pasture feed. In other circumstances cattle are agisted in the short term when a farmer may have a large number of

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cattle that need extra feed before transport to a market agrarian — relating to agriculture eg the agrarian revolution agribusiness — a type of commercial farming. Farming is considered a business with land owned by large corporations that have diversified into agricultural activity. These types of farms are typically large scale, land is intensively farmed, there is a high input of chemical fertilisers and pesticides, production is capital intensive with the heavy use of machinery and high-technology agricultural land use — also referred to as farming. Examples of agricultural land use include dairy farming, wheat farming and coffee plantations A-horizon — the upper part of a soil profile consisting of organic material and where the processes of leaching, soil creep and slope wash are common. The organic activity of plant roots and the activities of worms and insects dominate the A-Horizon (see figure 53) air mass — a parcel of air that has similar conditions at any horizontal position even though separated by tens or hundreds of kilometres. An air mass may extend for over 1000 kilometres and may extend from ground level up to 5 kilometres in altitude. Temperature and humidity characteristics are similar across the air mass at 1 kilometre; temperature and humidity conditions are similar across 3 kilometres altitude etc. Air acquires the characteristics of the surface over which it passes. So a parcel of air that lies over the Coral Sea off northeast Australia for a few days has characteristics that are warm and moist. The air mass may move onto the coast and inland. The land then becomes relatively moist air pressure — the weight of the air above. The weight of the atmosphere exerts a pressure; this is measured using a barometer in units called hectopascals (eg 1000 hPa)

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albedo — the proportion of solar radiation reflected from the surface. Lighter coloured surfaces have a higher albedo than darker coloured surfaces • Snow reflects 40-70% of radiation; this explains the glare of snowfields • Forests reflect approximately 15% of radiation • Tarred roads reflect 5-10% of radiation because so much radiation is absorbed rather than reflected. Dark surfaces such as these become very warm algae — a group of simple plants that contain chlorophyll enabling them to photosynthesise. Algae can be found in aquatic areas such as rivers or any moist areas alkalinity — a term to describe the pH of a soil or water; a pH over 7.2 indicates alkaline conditions (see acid soil and pH) alliance — a political association between two ‘states’ (countries, provinces etc) for mutual benefit such as political alliances and military alliances (eg ANZUS, NATO) allochthonous — usually referring to sediment, allochthonous material is that which has been transported from one place, deposited and then forming rock. For example sediment transported from mountains, deposited in the form of a delta, then after million of years forming sandstone (see autochthonous) alluvial — related to sediment that has been deposited by flowing water alluvial fan — a low, cone-shaped, deposit on land formed where a sediment-laden stream deposits its load as a result of an abrupt change of slope. For example in arid environments alluvial fans are common where a mountain stream deposits its sediment on a low-lying plain at the foot of a mountain or mountain range alluvial soil — soil that has developed from material than has been deposited


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by flowing water such as a stream. Alluvial soil is very fertile and is used for various types of intensive agriculture such as rice growing. Also settlement in many developing countries tends to be very dense on the fertile alluvial floodplains of rivers such as the Ganges River and river deltas such as the Mekong River delta (see alluvium) alluvium — unconsolidated (loose) material, such as sand, gravel and clay, that has been deposited by water. Alluvium can be deposited on the floodplain of a river following floods (see figure 25) alp — referring to high mountain peaks such as the Himalayan Alps and the European Alps. In many instances ‘alps’ are referred to as the pasture for cattle grazed under transhumance alphanumeric — a location system based on a grid. Unlike grid references points are located using letters across the top of a map and numbers along the side or sides (as in a street directory) alpine — relating to mountain environments; strictly that area above the tree line and below the area of permanent snow altimeter — an instrument in aircraft and used by land surveyors in determining height above sea level altiplano — a windswept, almost treeless, high altitude plain in Bolivia. The dominant form of land use is that of grazing llamas, alpacas and sheep altitude — the vertical height of the land above sea level Amazon River — located mainly in Brazil, South America, the Amazon is the second longest river in the world and with the largest discharge of 5,600 km3 anabatic wind — a warm wind blowing upslope. When valley slopes are heated, for example by the Sun, the warm air rises causing a wind to blow up the slope. Such warm winds are dangerous in areas prone to bushfires (see föhn effect and katabatic wind)

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anabranch — the name given to a stream that leaves the main river channel then joins up with it further downstream. Anabranches are common in areas such as where a stream (or glacier) flows into an area of much lower gradient. The low gradient and high sediment load, such as on river deltas (eg the Ganges /Brahmaputra delta) as well as at the foot of glaciers, where there is often sediment-laden snowmelt, lead to many interconnecting and crisscrossing channels (see braided river) anaerobic — a term used to describe conditions where oxygen is not available. Anaerobic conditions commonly exist in the deep waters behind the walls of dams and at the bottom of peat bogs and swamps (where little or no life exists) (see aerobic) anastomosing — referring to anastomosing channels. As some streams divide, especially in their lower reaches, sediment-laden waters form many interlocking channels as in braided streams ancillary services — additional services that a firm needs to function more effectively — beyond the main services provided to it Angkor Wat — a stone temple in Cambodia once part of the Khmer Republic which flourished between the seventh and twelfth centuries angle of repose — usually defined as the angle at which sediments come to rest. The angle of repose is the maximum angle that grains remain in place without collapsing downslope. However the maximum angle that grains are at rest may be greater than the angle of repose due to internal friction and the shape of individual grains animate energy — human labour and draught animals are the main forms of animate energy (as opposed to inanimate energy such as oil, coal and natural gas)

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animism — a system of belief in which natural objects such as trees and rocks are said to have spirits annual temperature range — the difference between the highest and lowest temperatures over a year Antarctic Circle — an imaginary line of latitude at 66½°S (see Arctic Circle) Antarctic Convergence — lies within the Southern Ocean surrounding the Antarctic continent, where the cold surface waters of the south (2°C) meet the warmer surface water of the north (4°C). This area is rich in marine life and forms an obvious boundary between flora and fauna to the north and south Antarctic Treaty — an international agreement between nations for the protection of Antarctica and Antarctic resources. The treaty was signed in 1961 with the objective of maintaining Antarctica for peaceful purposes and providing for the protection of its flora and fauna. It was signed by 16 nations engaged in Antarctic research – Argentina, Australia, Belgium, Chile, (former) Czechoslovakia, Denmark, France, Japan, the Netherlands, New Zealand, Norway, Poland, South Africa, United Kingdom, USA and (the former) USSR. No country owns Antarctica or a piece of Antarctica; rather various countries such as Australia have laid claim to various parts of Antarctica in the event that the continent may be ‘split up’ at some future date. Australia has by far the largest claim antecedent drainage — a drainage system that has maintained its course despite localised uplift of land antecedent stream — a stream that has maintained its course despite localised uplift; its course has not been diverted anthropogenic — a term used to describe those features that are a result of human activity. For example an anthropogenic effect is the construction of buildings anticline — the arch in a fold of sedimentary rock where rock layers

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have been forced to rise in mountain building (see fold mountains) anticyclone — an area of high pressure (see figure 26) antipodes — places on the Earth’s surface directly opposite each other such as China and Argentina. Australia is sometimes referred to by the British as the antipodes ANZUS — ANZUS Council; treaty signed by Australia, New Zealand and the United States apartheid — a system of racial segregation; an example of this was its adoption by the largely Afrikaner National Party of South Africa in 1948 APEC (Asia Pacific Economic Cooperation) — created in 1993 forming an important economic and trade association for Asia-Pacific nations – New Zealand, Japan, South Korea, Canada, China, Taiwan, Mexico, Papua New Guinea, Chile, Thailand, Philippines, Malaysia, Singapore, Brunei and Indonesia apedal — soil material showing no internal organisation in the form of peds (see pedal). Soils dominated by sand are often apedal aphelion — the point at which an orbiting body, such as the Earth or a comet, is furthest from the Sun. On Earth it occurs on approximately 4 July – at 152 million kilometres aphotic zone — area of a body of water that light does not penetrate, such as below approximately 200 metres in the open ocean (see photic zone) apogee — the point at which an orbiting body, such as the Moon, is furthest from a planet such as the Earth Appalachia — that area of the eastern United States that includes the area of the Appalachian Mountains (including states such as Virginia and Pennsylvania) applied geography — the application of geographic knowledge and skills in the acquiring of new knowledge and the solving of problems in the biophysical, social and economic environment. Examples where the


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application of geographic knowledge and skills is incorporated is in the areas of town planning, Environmental Impact Statements, land use zoning, population studies, census analysis and in the large field of tourism aquaculture — the commercial growing of marine or freshwater animals and plants in water eg oyster growing and trout farming (see mariculture) aquatic — a term relating to water or living in a water environment. For example fish are aquatic animals (see terrestrial) aquiclude — an impermeable barrier that restricts the flow of groundwater in an aquifer. A rock type such as shale may restrict the flow of water from sandstone aquifer — a permeable rock formation that stores and transports groundwater and is often used for irrigation (eg the Great Artesian Basin in Eastern Australia). Different types of aquifers include: • Surficial Aquifers – occur in alluvial deposits in river valleys, deltas and some sand dunes. These large aquifers such as on Fraser Island (Qld) provide a permanent water source for many perennial rivers • Sedimentary Aquifers – occur in consolidated sediments such as sedimentary rocks as in the Great Artesian Basin covering much of the eastern half • Geologic Aquifers (or Fractured Rock Aquifer) – occur in some igneous rocks that have been modified by Earth movements and trapping some water. These are limited in extent and occur far less frequently than other types of aquifers arable — a term used to describe land that is able to grow and support crops. The land has characteristics such as gently sloping land, fertile soils and a temperate climate (one lacking extremes of temperature and rainfall)

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arboriculture — the cultivation of trees (see silviculture) arboreal — relating to trees arboretum — a collection of living plant species such as trees and ferns for both study and the display of their diversity of form archipelago — a large group of islands such as the Indonesian archipelago and Philippine archipelago Arctic Circle — an imaginary line 66½°N. North of the Arctic Circle there is one 24-hour period when the Sun does not set and one 24-hour period when the sun does not rise area reference — a four figure map reference used on a topographic map eg 2475 (see figure 40) arête — a very sharp, rocky mountain ridge in a once glaciated upland region arid environment — a dry environment. Arid environments such as deserts are characterised by low average annual precipitation and a sparse vegetation cover Aristarcus — Aristarcus of Samos (the Mediterranean) approximately 2200 years ago was the first person to suggest that the Sun rather than the Earth is at the centre of the planetary system and that all the planets revolve around the Sun rather than the Earth (see Copernicus) arithmetic mean — the average of a set of numerical data; eg scores of 5, 8, 9, 9, 10, 13 have a average or arithmetic mean of 9 – that is the sum of the scores (54) divided by the number of scores (6) arroyo — a dry river bed with steep sides in an arid or semi-arid environment. It typically flows after short intense bursts of rainfall; the term is used mostly in SW USA and Mexico (see wadi) arterial roads — the main roads transporting the bulk of vehicular traffic artesian well — a well that penetrates an aquiclude to reach the aquifer below that releases water to the

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surface that has been held under pressure asbestos — a fibrous form of some minerals such as chrysolite, a fibrous serpentine mineral. It has been used as a form of insulation in houses as well as part of the constituents of some roofing materials. Prolonged exposure to asbestos can lead to Asbestosis as well as the cancerous Mesothelioma asbestosis — a disease of the lungs caused by the inhalation of asbestos fibres. As the fibres scar the lung chronic breathing difficulties occur ASEAN — Association of South East Asian Nations Ash Wednesday — the name used to refer to the devastating fires in Victoria and South Australia, 16 February 1983. Seventy-six people died, over 3500 were injured, 17,000 homes were destroyed and 300,000 sheep and 18,000 cattle were killed aspect — the direction that a feature, such as a building or hill slope, faces. Slopes, for example, can be described as having a northerly aspect. This

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means that the slope faces north. The aspect of a slope influences its microclimate. A north-facing slope in the Southern Hemisphere will be warmer than slopes with a southerly aspect. Slopes with a northerly aspect as a result tend to be drier. Slopes are also described as having a sheltered or an exposed aspect. A slope with a sheltered aspect is protected from the elements of the weather such as strong winds and high temperatures. Slopes with an exposed aspect receive the extremes of weather such as high and low temperatures and strong winds asthenosphere — a zone of very hot, partially molten, rock within the Earth’s upper mantle (extending from approximately 100-300 km below the surface to a lower limit of 700 km). It is often described as ‘plastic’ because the rock seems to flow as a result of the internal heat of the Earth – and provides part of the driving force behind plate movement over the Earth atmosphere — the gaseous envelop surrounding the Earth (Figure 2). The Earth’s atmosphere consists of, by volume, 79.1% Nitrogen, 20.9%

Figure 2 – The Atmosphere

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Oxygen, 0.03% Carbon Dioxide and traces of other gases such as water vapour, Ozone, Argon, Krypton, Xenon and Helium. The atmosphere extends upwards of 120 km and includes the Troposphere, the Stratosphere, the Mesosphere and the Thermosphere atoll — a continuous, unbroken coral reef enclosing a lagoon attrition — the wearing or rubbing away by the friction of a particle or particles against another. When particles such as sand, or even large rocks, are transported by rivers, waves, wind or even glaciers the particles are worn down by their rubbing against each other Aurora Australis — white and coloured lights in the upper atmosphere (the Ionosphere) south of the Antarctic Circle. Solar radiation entering the Earth’s atmosphere interacts with molecules to produce what are also known as the southern lights Aurora Borealis — white and coloured lights in the upper atmosphere north of the Arctic Circle (see Aurora Australis) Australopithicus — an ancestor of the species Homo (of which people are a part). It is assumed that Australopithicus was an evolutionary dead end and was replaced approximately 1.8 million years ago by the species Homo autochthonous — usually referring to sediment, autochthonous material is that which has developed in situ (it has not been transported to the present site by agents such as wind or water). Evaporites are examples of autochthonous materials

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automation — the introduction of machinery into the production process. Automation has increased in many industries such as the car industry and in the production of electronic equipment, with the introduction of devices such as robots in car production and the use of computer technology. This has had the effect of reducing production costs, increasing output and producing materials of a uniform quality autotroph — an organism that is able to produce its own food. The various species of vegetation are autotrophs. They produce their own food via the process of photosynthesis (they are also called self-feeders). Autotrophs are commonly referred to as ‘the producers’ (see heterotrophs) autumnal equinox — an event that is the result of the Earth’s revolution around the Sun. In the Southern Hemisphere this event occurs 20-21 March. At this time the Sun is directly over the equator (see spring equinox) avalanche — the fast, down slope movement of soil and rock or snow (also called a debris avalanche) average — see arithmetic mean azimuth — the horizontal angle measured in a clockwise direction from true north to another point. As a result the azimuth of a point of 0º is north, 90º is east, 180º is south azonal soil — a young soil lacking definite horizons. These soils lack full development and occur outside climate and vegetation zones suggested by the zonal model of soil formation

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new geography dictionary geography dictionary new dictionary new geography

B

backswamp — low-lying, swampy areas on the floodplain of a stream. These areas can cover a wide area especially between the channels of meandering streams or the vast plains beyond a river’s levee bank. These areas are sometimes used for agriculture because of the often alluvial soil available or even for settlement (although the area is very flood prone) (see figure 25) backwash — the return flow of water back down the beach face after a wave has broken (see also swash) badlands — areas of extremely eroded land. The land shows evidence of deep gully erosion over a wide area (a term originally applied to the area of southwest USA) bahada — a landform at the foot of a highland area where a number of alluvial fans has coalesced (or joined) balance of payments — the difference between the value of the import and export of goods. A ‘favourable balance of payments’ is when exports exceed imports of goods; an ‘unfavourable balance of payments’ is when imports exceed exports of goods balance of trade — the difference between the value of the import and export of goods and services ball and chain — an indiscriminate form of land clearing whereby two tractors or bulldozers, linked by a chain 50 m to100 m long, with a large sold metallic ball at the centre of the chain. All in the path of the ball and chain is felled baobab — a large tropical African tree with a very large trunk Banksia — a native Australian plant named after Sir Joseph Banks (figure 3 16

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colour). The Banksia can range in form from a shrub to a small tree. Its coneflowers and rough bark make it distinctive in vegetation communities. Some varieties of this species are the Banksia serrata with its distinctive cream-coloured flower cone and serrated leaves, Banksia ericifolia with its large orange coloured cone and small thin leaves and Banksia marginata with its much smaller cream/yellow cone and under leaf silver colour bar — an accumulation of sediment (usually sandy material) within streams or offshore from the beach (see figure 14) barchan dune — a crescent-shaped sand dune moving across the surface with its ‘arms’ pointing downwind (typically found in the Sahara and Kalahari sandy deserts in Africa) (see figure 20) bare fallow — a fallow period where the soil has no vegetation or crop cover barefoot doctor — during the 1960s Mao Tse Tung introduced a program to improve the health of rural people. Local people were allowed to treat minor illnesses while still engaging in their agricultural lifestyle. These people became known as barefoot doctors. There are almost three million barefoot doctors in China today barrage — a large structure across a river to both impound the water and to make the body of water deeper than that of the original river. Barrages have typically been associated with the generation of hydroelectric power as a result of the energy created by the rise and fall of the tides (especially) at an estuary. This energy is used to turn


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turbines to generate electricity (eg La Rance estuary, France) barrier beach — a long narrow sandy beach parallel to the shore-line which is permanently above sea level – often with a lagoon between it and the land behind. In this case it is often called a barrier island. Along the NSW coast, Australia, there are two distinctive sand systems – an inner barrier and an outer barrier. The outer barrier is a narrow dune system close to the coast developed over the last 4000–6000 years ie after the sea level rise following the last glaciation. The inner barrier is further inland (seen especially on the North Coast of NSW) and about 1–2 metres higher than the surrounding land. It is believed that this sand system formed as much as 80,000 years ago during the last interglacial when sea level was about 2–3 metres above present levels (see figure 14) barrier island — a long narrow island, parallel to the shoreline, composed of sand, built by wave action and protecting the coastline from erosion by wave action (see figure 14) basalt — a fine-grained volcanic rock formed from a lava flow. The small crystals in basalt are the result of fast cooling near or on the Earth’s surface that inhibits crystal growth baseflow — the water supplied to a stream from groundwater. Baseflow provides a constant contribution to overall discharge in a stream. The rises and falls in the amount of water flowing in a stream are the result

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of rapid changes in precipitation and runoff within the stream’s catchment area base level — the lowest level to which a river will erode. A river will erode its bed until its outlet reaches base level. This is usually sea level. In a graded river base level is reached but the upper reaches of the river have the characteristic of the river being able to transport its load (sediment) but it does not have the energy to erode its bed. In areas of internal drainage a river’s base level may be a lake such as Lake Eyre, South Australia batholith — a large mass of igneous rock formed at great depth beneath the Earth’s surface. It may extend for tens or hundreds of square kilometres bathytherm — a line joining places of equal water temperature (especially in the oceans) bazaar economy — an economy in which local trade is very informal and goods are exchanged after much faceto-face haggling over price beach — an accumulation of sediment derived from a water source such as a river or sea waves. Although sediment is commonly sand-sized particles, beaches can be composed of larger materials such as pebbles 5–10 cm diameter to large boulders (see Table page 19). Sediment is typically moved by waves, currents or tides. Beaches are part of a larger beach system. Offshore sand can accumulate forming an offshore bar over which waves can break as the water becomes shallower. As the waves

Figure 4 – Stages in the Development of Successive Parallel Dunes Metres

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5

0

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Figure 5 – The Beaufort Scale Official wind speed symbol on weather map

Description

How to recognise wind speed

Comfort to people walking

0–0.5

Calm

Smoke rises vertically

No noticeable wind

1

0.5–1.5

Light air movement

Smoke drifts, leaves move

2

1.5–3.5

Light breeze

Flags flutter, small branches move

Wind felt on face

3

3.5–5.5

Gentle breeze

Flags extended

Clothing flaps

4

5.5–8.0

Moderate breeze

Wind sock lifted halfway up

Hair blown about

5

8.0–10.5

Fresh breeze

Crests (white horses at sea)

6

10.5–13.5

Strong breeze

Wind whistles, big branches sway

You have to lean against the wind when walking

7

13.5–17.0

Near gale

Wind sock extended, whole trees sway

Umbrellas blow inside out, difficult to walk steadily

8

17.0–20

Gale

High waves at sea

Difficult to balance in gusts

9

20.0–25.0

Strong gale

Tiles are blown from rooftops

People are blown over

10

More than 25.0

Storm

Trees uprooted

Beaufort Force

Wind speed (m/s)

0

1 half feather

1 full feather

2 full feathers

3 full feathers

1 flag 1 flag and 1 full feather

Admiral Beaufort devised this scale for measuring winds at sea in 1805. His scale was given symbols and adapted for use on land. We still use it today. Source: J Frew, Geography fieldwork projects, Nelson 1999, p 34.

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Sediment texture classes and related particle size Texture Class Size of Particles (mm) Boulders >256 Cobbles 64 Gravel 2 Coarse Sand 0.2 Fine Sand 0.02 Silt 0.002 Clay 0.0002 Source: J.P. Harte and J.D. Taggart eds, Approaches to fieldwork in senior geography, GTANSW, 1986, page 62.

break and surge towards the shoreline the swash brings with it sand to build up the beach face (and the backwash returns sand seaward). As sediment is built up a large sand deposit, a berm, forms. This berm comprises what most people associate as ‘the beach.’ At the back of the beach (or berm) more sand deposits accumulate forming a series of sand dunes such as embryo dunes and foredunes (Figure 4). A distinctive profile can be built up of a beach system each different according to the processes operating and the materials available (such as sand or pebbles) beach cusp — see cusp beach face — the zone on a beach where the water moves up the beach (the swash) and water returns down the slope (the backwash) to the surf zone bearing — an angle in degrees which gives the direction of one point on the Earth’s surface to or from another point Beaufort scale — a scale used for recording wind speed (Figure 5). A scale often used with each number indicating the effect of the wind on various features that we can see bed — a layer of sedimentary rock bedding plane — a flat, parallel surface i) separating different grain sizes in rocks that have been laid down under different conditions; or ii) indicating successive layers of sediment laid down

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under particular depositional environments (such as by a river, lake or wind). Bedding planes can be seen on the exposed areas of rock cuttings along the sides of some major roads as well as the steep walls of some river valleys (figure 6 colour) bedload — the sediment carried by a body of water such as a river along its bed or bottom. Particles that are moved in this way are too heavy to be transported in suspension so they slide or roll along the bed of the stream. A river might be transporting sediment in suspension but if the velocity of the flow decreases the river cannot carry the heavy particles. The particles then drop to the bed of the river and can be rolled along in the current bedrock — the solid rock beneath unconsolidated material such a soil Benioff zone — a long zone that forms deep within a subduction zone where one plate plunges under another. It can extend to a depth of 700 kilometres where heat is generated due to friction and the radioactive decay of sediment. The Benioff zone is also the source of deep focus earthquakes (see figure 17) benthic — a term used to apply to features at the bottom of water bodies such as lakes, rivers and oceans benthic-macro-invertebrate — bottom dwelling invertebrates in streams that can be seen with the naked eye. Benthic-macro-invertebrates include the Mayfly, Stonefly and Dragonfly nymphs as well as Waterstriders, Water Beetles and Yabbies. These and other organisms are useful as indicators of water quality in many streams benthos — a term used to refer to organisms living at the bottom of water bodies bergschrund — a crevasse occurring between the ice of a cirque and the mountain wall behind it; this has formed because the ice naturally moves downslope under the influence of gravity

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Bermuda Triangle — an area of the western North Atlantic Ocean (off the southeast coast of the USA) where a number of planes and ships have supposedly disappeared. The triangle is generally bounded by the lines between Cape Hatteras (North Carolina), Bermuda and Miami (Florida) Bhopal — a town in India that was the site of a major pesticide disaster December 3, 1984. The release of toxic fumes from a factory owned by Union Carbide led to more than 2500 people dying and over 200,000 people injured B-horizon — a layer in a column of soil material, below the A-Horizon, that has undergone complete weathering. The character of this horizon is dependent on a number of factors such as parent material (bedrock), slope, climate, vegetation and the time taken to produce this soil. For example soil developed on shale will have a high clay content. The Bhorizon shows evidence of vertically operating processes such leaching and illuviation (see figure 53) biface — a stone tool that results when two faces have been worked or chipped away so as to give a sharp edge. Bifaces are common tools used by early Aboriginal groups for skinning animals and for use as weapons bifurcation ratio — the ratio of the number of streams in one order to the number of streams in the next highest order

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bilby — a small native marsupial found in small scattered colonies, in desert and semi-desert areas of Australia bilateral agreement — an agreement between two nations (see multilateral agreement) bilateral aid — see foreign aid billabong — a waterhole that fills during floods and usually formed from a former river (meander) channel (see oxbow lake) bimodal — in a set of statistical data where there are two common scores the set is said to be bimodal (see mode) binary settlement pattern — where there exist a few large cities and a long tail of much smaller cities (as in Australia); (see primate city, rank size, figure 57) bioaccumulative — the characteristic of some substances, such as lead (and other heavy metals), to accumulate in the tissue matter of animals. In many instances, bioaccumulatives are harmful to life biocide — a chemical used to kill living things such as insects biodiversity — the variety of all lifeforms; the plants, animals and micro-organisms and the genes they contain as well as the variety of ecosystems they form biogas — gas generated from the breakdown (fermentation) of organic waste. The gas produced (largely Methane) is used for heating and cooking in many rural areas of developing countries

Figure 7 – Biological Oxygen Demand for various pollutants (mg per litre)

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biogeochemical cycle — the cycling of minerals and nutrients (organic materials) in the global ecosystem. The products from the weathering of materials and the breakdown of organic matter are cycled and recycled through the atmosphere, hydrosphere, lithosphere and biosphere to maintain the functioning of the biophysical environment. Examples include the carbon cycle, the nitrogen cycle and the phosphorus cycle (see figures 9 and 46) biological diversity — see biodiversity biological oxygen demand — a measure of the amount of dissolved oxygen in waterways such as rivers (Figure 7). Such dissolved oxygen is used by fish, microorganisms as well as in the decomposition of organic matter. There is a large BOD involved in the breakdown of fats in water, for example. Where there is a large BOD the loss of dissolved oxygen can lead to the waterway being unable to support a diverse aquatic life. In areas where BOD is low only a small variety of low, oxygen-tolerant species survive such as in the deep, cold oxygen-poor waters behind dam walls (see eutrophication) biomass — the total weight of organisms in a particular area. biome — a vegetation community occupying a large area of the Earth’s surface. Examples of biomes include tropical rainforests, grasslands, tundra and temperate forests biophysical environment — an alternative term used for the natural environment. The biophysical environment is made up of the atmosphere, lithosphere, hydrosphere and biosphere. There are many features that make up the biophysical environment. Biophysical environments include forests, deserts and oceans. Biophysical features include mountains, clouds, sand dunes, rivers and plants bioremediation — using biological techniques to overcome environmental problems; for example

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planting saltbush to address dryland salinity; to introduce a competitor to control an insect pest biosphere — that part of the biophysical environment made up of living things. The biosphere includes parts of the atmosphere, the lithosphere and the hydrosphere — because various types of life exists is these ‘spheres’ biosphere reserve — an area established with the primary aim to preserve this representative area as a major ecological resource. The concept of Biosphere Reserves was put forward by UNESCO in response to worldwide environmental degradation and the unacceptably high rate of species extinction. Australia has twelve biosphere reserves — Uluru and the Tasmanian Wilderness are also World Heritage Sites; most are national parks biota — plant and animal life located in a particular area at a particular time biotic — a term used to refer to the living parts of the biophysical environment (see abiotic and ecosystem) bituminous coal — commonly known as black coal; a higher quality coal than lignite black economy — that part of the job market where information is provided to the government for the reason of evading taxation. The Black Economy operates side by side with the legal economy but it exists because of the legal tax it avoids paying black ice — a thin sheet of frost (ice) without the usual white colour usually associated with frost. Black ice is sometimes very difficult to see while travelling on roads bloc — a group such as countries or commercial organisations that, under formal agreement, operate as one body with similar objectives. This is often seen as a group making decisions for the mutual benefit of each member of the group. There are trading blocs such as OPEC and economic blocs such as the European Union (EU)

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block fault — vertical movement in the Earth’s crust along almost parallel fault lines leading to a series of uplifted blocks of land often with steep escarpments. In many cases these escarpments have been eroded leading to much more gentle slopes but the fault areas can nevertheless be determined via geological fieldwork block lava — lava that has solidified forming a rough and jagged surface (see aa) block mountain — a mountain or area of high relief that has been uplifted by Earth movements along fault lines blockstream — a stream-like accumulation of large rocks greater than 30 cm across which are more extensive downhill than across the slope and are more or less channeled. Blockstreams are typical of periglacial environments blowhole — a hole or vertical column in a sea cliff through which large waves force water upward by hydraulic action boat people — refugees that leave one country and arrive in another by boat. People leave their home country with very few personal possessions and on an often less-than-seaworthy boat. Many boat people have arrived in Australia since the 1970s from Kampuchea, Vietnam and China – and more recently from southwest Asia such as Afghanistan BOD — see biological oxygen demand bog — a lowland area saturated with water with decaying vegetation producing relatively acid soil material bolson — an inland basin surrounded by mountains found in arid and semi arid environments (a term used especially in SW USA and Mexico) bolus — soil material that is worked or rubbed in the hand to determine soil texture. A palm-full of soil is collected from a particular soil horizon; a small amount of water can be added. The material is then squeezed and rubbed between the thumb and forefinger. This is a bolus. The material is then rubbed between the thumb

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and forefinger to ensure the bolus is well-mixed. The bolus can then be rubbed between the palms to determine if a ‘ribbon’ can be formed (ie a length of material that looks like a ‘skinny sausage’ (see soil texture) bore — a deep drill hole tapping an aquifer (see tidal bore) boreal — a term describing a feature that belongs ‘in the north.’ Boreal is typically applied to those cold areas of northern North America, Europe and northern Asia and in particular to the coniferous forests of these areas brackish — a term used to describe water that has a high concentration of salt in solution but is not as saline (or salty) as sea water braided river — a river that divides into many interconnected channels. They are typically found in areas of low gradient and where the sediment load of the river is high. An example where braided streams can be found is on low-lying plains where a river has passed through an area of severe erosion (eg the mouth of the Ganges River (Padma River) and the Brahmaputra River in Bangladesh) Brandt line — an imaginary line drawn on a world map separating developing countries from developed countries. In 1980 the Brandt Commission published a report called ‘NorthSouth’ highlighting the great disparities between countries in various development indicators and particularly the plight of the developing world in terms of malnutrition, illiteracy, low incomes and high birth and death rates. The Brandt line highlights the developed countries (called The North) and the developing countries (called The South) breccia — a type of rock consisting of many angular fragments within a much finer matrix — very different to conglomerate rock that consists of much more rounded pebbles typically a result of fluvial erosion and deposition


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brigalow — a type of scrub found in central and southern Queensland and northern NSW. It consists mainly of low acacia (wattle) trees and bushes broadacre farms — commercial farms covering a large area especially in the drier mid-latitude areas with land devoted to crops such as wheat and cotton brown haze — a form of air pollution found especially over cities. Fine particles in the air from natural sources, such as dust, pollens and salt, as well as from human sources, such as car exhausts and incineration, has the effect of reducing visibility. Sea breezes contribute to brown haze along the coast bringing high concentrations of salt onshore. Brown haze is so common over cities now that the increasing mix of chemical pollutants from cars and industry has contributed to a much more severe type of pollution called Photochemical Smog built environment — that part of the environment around us created by people eg factories and cities bund — a low earth wall constructed around a field such as a padi field to control the flow and level of water necessary in crop production

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Burgess, E.W. — in 1924 Burgess attempted to identify and explain urban areas within Chicago, USA based upon the outward expansion of the city and the socio-economic groupings of its inhabitants. His research led to the development of a model of urban structure comprising of a series of concentric zones; the model became known as the concentric zone model (see figure 58) bustee — a name for shanty towns in India butte — a flat topped hill that is taller than it is wide commonly found in arid environments. A butte is formed mainly by the lateral, or sideways, erosion at the base of an outlier, or small hill. In many cases lateral erosion has been more rapid than erosion at the surface due to a more erosion resistant ‘capping’ such as laterite on the surface (see figure 20, mesa) Buys Ballot’s Law — this law states that if you stand with your back to the wind in the Southern Hemisphere low air pressure will be on your right and high pressure will be on your left by-law — a law made by a local authority for the control of its own affairs

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new geography dictionary geography dictionary new dictionary new geography

C

cadastral map — a large scale map showing land ownership. Individual landholdings can be identified calcareous — any substance, such as a rock or soil, containing a large proportion of calcium carbonate caldera — a large basin-shaped depression resulting from the explosion or collapse of the centre of a volcano Callistemon — a vegetation species commonly called ‘bottlebrush’ calving — the separation of ice from the front of a glacier. Where the front of the glacier reaches the sea the ice breaks off and may float in the ocean in the form of an iceberg Cambrian Period — a period of the Geological time scale extending from about 570 million years ago to 500 million years ago. The Cambrian Period saw an explosion in the number and diversity of life on Earth (see figure 27) campos — a tropical grassland in Brazil (South America) south of the lush equatorial rainforests, similar to the savanna in Australia cane toad — an animal introduced into Queensland Australia in 1935 in an attempt to control the Cane Beetle that threatened the sugar cane industry. Now the Cane Toad has become a pest and a major environmental problem as it poses a serious threat to many native animal species (in Queensland, northern New South Wales and eastern Northern Territory) canopy — the top layer of a closed forest consisting of the bulk of leaves and branches (figure 8 colour) 24

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Cape Horn — the southern-most point of South America capital intensive — refers to production such as sheep farming or building construction where a lot of capital equipment (such as machinery) is used as opposed to a lot of labour. Capital intensive production is common in more developed countries, such as Australia (where more machinery is used) than developing countries such as those countries of Southeast Asia (where more physical labour is used); see labour intensive carbon credit — a permit granting the holder a right to emit a specific amount of greenhouse gas (such as carbon dioxide and methane). The Kyoto Protocol was agreed to in December 1997 where it assigned amounts, or quotas, of emissions agreed to by developed countries. Carbon credits are obtained via the process of carbon sequestration; ie any process that lowers the atmosphere’s concentration of greenhouse gases. The Australian Government has indicated a plan to introduce ‘carbon credit trading’ in order to meet international obligations under the Kyoto Protocol. World policy makers are in the process of creating a global market for carbon. carbon cycle — the cycling or movement of carbon through the environment (Figure 9). Carbon exists in many forms and is stored within the biosphere, lithosphere, atmosphere and biosphere. Carbon in the form of carbon dioxide occurs in the atmosphere and dissolved in the oceans. A large proportion of carbon is stored within the lithosphere. Calcareous sediments on the ocean


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floor eventually turn to rock such as limestone. Carbon from decomposed vegetation has formed coal seams and oil and natural gas deposits within the Earth’s crust over millions of years. These are unevenly distributed around the world in areas called sedimentary basins such as beneath the Middle East. Carbon is transferred through the biophysical environment. Following mining and its use as a heating source (such as in coal-fired power stations) and as an energy source for transport, carbon is added to the atmosphere. The carbon dioxide occurring naturally in the atmosphere as well as that added from the burning of fossil fuels is taken up by vegetation around the world in the process of photosynthesis. Plants absorb carbon dioxide producing tissue matter. This is later returned to the lithosphere as a result of decomposition. carbon dioxide — a minor gas (by volume) in the atmosphere comprising one carbon atom and two oxygen atoms. Carbon dioxide is stored in the lithosphere (eg as oil, coal and natural gas), in the atmosphere, in the oceans as well as in the biosphere (eg vegetation). Carbon Dioxide is released into the

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atmosphere by the burning of fossil fuels and the burning and clearing of vegetation (see carbon cycle). It is a major greenhouse gas contributing to global warming (see Greenhouse Effect) carbonation — a process whereby dissolved carbon dioxide in water acts as a weak acid and dissolves particular minerals. Carbonation is a chemical process that leads to the weathering of minerals in some rocks. For example the carbon dioxide in the atmosphere can dissolve in water droplets. This water becomes slightly acid (see acidity). When this weak acid (called a weak carbonic acid) comes into contact with carbonate minerals that make up limestone, for example, these minerals dissolve. In urban areas the cements used in building materials, relying on carbonates, are dissolved by the acid in acid rain eventually weakening the building structure. carcinogen — a cancer-producing substance eg asbestos and radioactive materials cardinal points — the four main directions shown on a compass – north, south, east and west (Figure 10) carnivore — an organism that consumes meat. Carnivores, such as lions and hyenas, consume herbivores

Figure 9 – The Carbon Cycle

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as a food source to gain nutrients and energy carrying capacity — the maximum number, or amount of activity that the land can support as a result of factors such as such as climate, soil, vegetation and water availability. Beyond this number or amount the land is unable to cope; it responds in various types of land/water/atmospheric degradation such as accelerated soil erosion, dieback and water eutrophication cartel — a group of individuals, companies or countries that together control the production, distribution, marketing and even pricing of particular goods. OPEC is an example of a cartel that controls aspects of oil production and pricing cartographer — a person who works with and/or constructs maps cartography — the making of maps and graphs for charts

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cash crop — a crop grown with the objective of producing a surplus for sale. Cash crops are grown primarily, but not always, as a single crop such as sugar cane, wheat, and canola. Cash crops are characterised by a high input of technology (such as High Yielding Varieties as a result of genetic engineering) and capital equipment such as machinery. Plantations in many developing countries are dominated by cash crops such as rubber, cocoa and oil palm Casuarina — a tree species commonly called a ‘she-oak.’ Casuarinas can be found in a variety of environments such as the taller Forest Oaks on the slopes of protected valleys and the smaller trees on drier plateau surfaces. They are adapted to relatively dry conditions by having long thin stems divided into segments. When broken these segments reveal small leaves (less than a millimetre in length) to reduce transpiration loss

Figure 10 – The four, eight and sixteen point compass

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catastrophism — the ideology or belief that Earth surface processes are not constant or uniform. The term is used to refer to the study of sudden events of large magnitude – intensive processes that have the effect of altering existing processes. For example earthquakes and tropical cyclones that occur suddenly with devastating force altering environments in such a way as to put into place new processes such as erosion creating unstable hillsides or river channels being directed on different paths (see uniformitarianism) catchment area — the total area from which material is received (Figure 11). With respect to a stream, a stream’s catchment area is the total area from which it receives water. The catchment may cover one square kilometre for a suburban creek or tens of thousands of square kilometres for rivers such as the Amazon River. The catchment area of the MurrayDarling river system is over one million square kilometres and extends from the southern part of Queensland to most of New South Wales, northern Victoria and southeast South Australia (see total catchment area)

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catena — a sequence of soil types that occur across a slope having developed over similar bedrock but reflect differences in vegetation cover, infiltration and the slope of the land cay — a cay is a low coral island formed when eroded coral debris, formed by the erosion of a coral reef, is washed to and collected in a particular area by the action of waves. They are known as coral cays CBD — see Central Business District CCAMLR — see Convention on the Conservation of Antarctic Marine Living Resources celsius (or Centigrade) scale — a temperature scale used around the world that shows the freezing point of water at 0°C and the boiling point of water at 100°C at sea level. With changing altitude the boiling and freezing point of water changes. For example as altitude increases water boils at a lower temperature. To convert to Fahrenheit temperatures to Celsius see the ‘conversions’ section in the Appendix of this dictionary census — the organised collection and collation of population numbers of an area such as a country

Figure 11 – Catchments

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Central America — a region of the North American continent that includes all countries between Mexico in the north and Panama in the south inclusive Central Business District — the main commercial, financial and retail area of a town or city. The CBD is often the site of initial settlement and with ready access to transport and communication links for the efficient transfer of goods, services and information central place — an urban centre that serves communities in its surrounding hinterland providing central goods and services central place theory — in the early 1930s an economic geographer, Walter Christaller, proposed an idea to explain the spatial arrangement of urban places across the landscape. He stated that urban centres, called central places, would provide goods and services to their hinterland. However those larger urban places providing higher order goods would have greater trading areas because people would be willing to travel greater distances to purchase such goods. As a result urban places would be located at distances reflecting the threshold population needed to support goods and services being provided by the central place. The range of these goods and services determines the trading area of that central place. These trading areas, in turn, are influenced by the range of the goods and services provided. Those centres with small threshold populations and small ranges will be more common and spaced more closely together; while those with large threshold populations and large ranges will be much fewer in number and spaced more widely apart. In this way a hierarchy of settlements develops. The theory is very unrealistic because of the many assumptions that have to be made such as central places located

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on a flat plain with no variation. We know however that such features as hills and rivers can influence the size and spacing of settlements (see high order goods) centrally planned economy — an economic system where the factors of production (land, capital, labour and entrepreneurial skill), marketing, distribution and consumption are controlled by a central government. Examples of Centrally Planned Economies are former communist China and Cuba centrifugal force — a force that encourages people and economic activity to leave an area; for example pollution, traffic congestion, transport costs – also called push factors. These forces also contribute to the process of counterurbanisation centripetal force — a force that attracts people or economic activity into an area (eg tax incentives, access to infrastructure, employment opportunities and educational facilities) — also called pull factors CFCs — Chlorofluorocarbons. A range of compounds of carbon, chlorine and fluorine. CFCs are used as refrigerants in fridges, freezers and air conditioners but also in plastic foams that make up many disposable cups and packaging. When released into the atmosphere the molecules that make up the CFC are split by ultraviolet radiation from the sun. This releases atoms of chlorine that attack the ozone molecules in the Stratosphere, leading to a thinning of the ozone layer, allowing increased amounts of potentially harmful ultraviolet light to reach the surface of the Earth (see Ozone Hole) chain migration — movement of people (migration) from a village to a large city in a series of steps; eg from a village to a smaller town, a larger town, a large city Chandler Wobble — the variation in the rotation of the Earth due to a slight wandering of the poles relative to the


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Earth’s surface. The Earth’s axis ‘wanders’ approximately 0º 0' 5" over a period of 14 months chelate — see chelation chelation — a process in which rock and soil material is broken down (weathered) as a result of the action of organic material. When water passes through leaf litter or decomposed organic matter generally it picks up organic acids. These organic acids combine with metallic elements in the soil forming what is called a chelate. The type of organic material influences the strength of this chelate and therefore the latter’s ability to break down the rock or soil material cheluviation — under the influence of gravity, the downward movement of dissolved minerals within soil material. As decomposing organic matter produces humic acids, especially in humid environments, these acids attack clays and rock minerals releasing iron and aluminium oxides (called sesquioxides). The deposition of this material (along with eluviated material) can produce a variety of hardpans within a soil profile chemical weathering — the break down of minerals into more simple minerals. Chemical weathering includes the processes of oxidation and carbonation. In a rock such as limestone (CaCO3 – calcium carbonate) acids in water breakdown (or dissolve) the limestone. The calcium ends up in solution in the water and the carbonate is given off as a gas chemotrophic — a term used to describe organisms that obtain their energy from a source other than light. They do this by using the energy from simple chemical reactions Chernobyl — a site in the Ukraine where one nuclear reactor hall of a nuclear power plant exploded on April 26, 1986, leading to the release of a radioactive cloud over the capital Kiev and later spreading over central and northern Europe. Many cancerrelated deaths have resulted

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chernozem — a fine-grained fertile soil, dark brown in colour and covering an extensive area in Eastern Europe such as the Ukraine, Romania and Hungary. These soils, often called Black Earths, are also found in the grasslands of North America and Australia where grasses provide rich humus material in the A-horizon to act as nutrients for any agricultural crops in these areas chinook — a dry warm wind blowing off the Rocky Mountains in North America. The normally cold air over the Rocky Mountains of the USA and Canada is warmed adiabatically as it is flows rapidly down the mountain slopes. The Chinook literally means ‘snow eater’ (see föhn) chlorofluorocarbons — see CFCs chlorophyll — the green colour in plants from algae to trees. They absorb sunlight in the process of photosynthesis C-horizon — the lower part of a soil profile, below the B-Horizon consisting largely of unweathered or only partially weathered bedrock (parent material) and little or no vegetation matter with the exception of some plant roots (see figure 53) chloroplast — part of a plant cell where photosynthesis takes place choropleth map — a map that uses changes in shading to show variations over the area of a map. A chorchromatic map uses various colours to show such variations over the map Christaller, W. — a German geographer who in the early 1930s proposed a model explaining the network of urban centres. Based on research conducted in southern Germany he proposed that there was an orderly spatial arrangement of urban centres over the landscape. His model became known as central place theory (see Lösch, A) cirque — a bowl-shaped, steep-walled feature on a mountain slope formed by the erosion of a small glacier – often containing a small lake (see figure 28)

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cirrus — a thin, wispy cloud typically seen at over 6 km altitude CITES — Convention on the International Trade in Endangered Species (of wild flora and fauna). The convention seeks to protect various species from excessive global trade contributing to their endangered status or their extinction

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citizenship — membership of a nation state that brings certain rights and privileges. Active and informed citizenship involves participation in community activities and public affairs (NSW Board of Studies) Ciudades Peridisdas — an illegal squatter settlement in Mexico City

Classification of Coasts – I

PRIMARY

COASTS: CONFIGURATION RESULTING FROM NON-MARINE PROCESSES

A: Land erosion coasts. Shaped by erosion of the land surface and subsequently drowned by sea-level rise sinking of the land, or the melting of ice caps i) Drowned river cut valleys – shallow estuaries; V-shaped valleys (ria coastlines such as eastern Australia) ii) Drowned glacial erosion coasts – deep water estuaries; U-shaped valleys (fiords such as the southwest coast of the South Island of New Zealand) iii) Drowned karst topography – embayments with oval depressions such as sinkholes (eg the Dalmatian coast along the Adriatic Sea) B: Land depressed coasts. Shaped by land-derived sediments that prograde to the sea coasts i) River deposition coasts a) Deltaic coasts form a lobe into the sea eg Mississippi Delta, Nile Delta b) Compound alluvial fan. Coastal plain at the base of mountains eg east coast of the South Island of New Zealand c) Outwash plain. Alluvial deposition formed on the outer margins of large glaciers eg glaciers in Alaska ii) Glacial deposition coasts a) Partially submerged moraine. Hummocky topography and straightened by marine deposition and/or erosion eg Long Island, New York b) partially submerged drumlins iii) Wind deposition coasts a) Dune prograded coast. Rare: part of Namibian coast (Africa) b) Dune coast. Where dunes are absorbed by a beach. The mouths of many river valleys iv) Landslide coasts. Masses fallen from cliffed coast eg Oregon (USA) C: Coasts shaped by volcanic activity i) Lava-flow coasts eg Hawaii ii) Volcanic collapse or explosion coasts. Concave bays on the side of a volcano eg Hanauma Bay Honolulu iii) Tephra coasts. Where fragments of volcanic material have built up the coast eg west Mexico D: Coasts shaped by diastrophic movements i) Fault coast. Straight fault scarps continuing below sea-level ii) Fold coasts. Where the coast has been recently folded iii) Sedimentary intrusion coasts a) Salt domes eg small islands in the Persian Gulf b) Mud lumps. Small islands resulting from the upthrust of mud. Short-lived eg near the mouths of the Mississippi estuaries E: Ice coasts. Where glacier fronts extend into the sea eg along most of the Antarctic coast Continued next page

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civic centre — that part of a town or city (usually in the centre) where there is a concentration of public buildings such as the town hall, public library and council offices civics — an identifiable body of knowledge, skills and understandings relating to the organisation and working of a society, including a country’s political and social heritage, democratic processes, government, public administration and justice system (NSW Board of Studies) clastic — related to sediment or rocks composed of fragments that have been derived from the weathering and erosion of pre-existing sediments or rocks – typically transported by water, gravity or ice to the present site clearfelling — the removal of all trees in an area typically as a result of the use of machinery by people cleavage — a tendency of minerals to split along a particular plane according to their internal structure. These lines of cleavage, showing lines of weakness, are not related to larger scale features such as bedding planes or joint lines climate — the average condition of the atmosphere over the long-term.

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A place is described as having a desert climate because it has been dry, or arid, for a long time eg for decades, hundreds or thousand of years climate change — the long term change in the processes operating in the global atmosphere as seen in changes such as in temperature and precipitation (see figure 12 ‘Techniques used for determining climate change’, Quaternary Period) climatic graph — a graph providing a summary of climate information about a place, such as temperature and precipitation climax community — a community of organisms that form the final stage of a natural plant succession. The vegetation is in balance with the surrounding natural environment; for example a woodland on a coastal foredune clinometer — an instrument to measure the angle of a slope closer settlement — see urban consolidation cloud — concentrations of water vapour in the atmosphere (Figure 13). As air is forced to rise it cools; water vapour condenses around condensation nuclei.

Classification of Coasts – II

SECONDARY

COASTS:

CONFIGURATIONS

RESULTING MAINLY FROM MARINE AGENCIES OR ORGANISMS

A: Wave erosion coasts i) Straightened by erosion. With gently sloping sea floors and rock platforms ii) Coasts made irregular by erosion B: Wave deposition coasts i) Coastal flats or plains built seaward by waves. Broad beaches upcurrent of groynes and the flats upcurrent ii) Barrier coasts. Separated from the mainland by lagoons or marshes eg eastern NSW Australia iii) Cuspate forelands. Large projecting sand spits with or without lagoons behind iv) Mud-flats or salt marshes eg northwest Australia C: Coasts prograded by organisms i) coral reef coasts eg Palau and the islands of the southwest Pacific Ocean ii) mangrove coasts eg Gulf of Carpentaria (northern Australia) D: Man-made coasts. Configurations resulting mainly from human activity eg reclaimed coastlines such in the Netherlands Source: R.U. Cooke & J.C. Doornkamp, Geomorphology in environmental management: a new introduction, Oxford University Press 1990, p272–273

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FIGURE 12 â&#x20AC;&#x201C; Techniques used for determining climate change

Climates change over the surface of the Earth over both short and long time scales. Many techniques are available to determine the chronology and changing environments of the Quaternary Period (the last 2 million years). Some of these include: i) Dendrochronology: also known as tree ring analysis this is an attempt to correlate the annual growth rings of trees with that of past temperature and precipitation levels in an area. Reconstructing past climates in this way can extend back 3000â&#x20AC;&#x201C;4000 years with some species of tree such as the Bristlecone Pine in southwestern USA ii) Varves: these are layers of sediment of different composition and texture reflecting the seasonal variations in glacial meltwaters. Coarse material is deposited at the foot of a glacier during warmer periods because the greater discharge can transport heavier sediment. As temperatures cool, less water drains from glaciers leading to only fine sediment being transported. In this way, pairs or couplets of alternating fine and coarse sediment reflect relatively warm or cool temperatures iii) Palynology: also known as pollen analysis this technique involves analysing pollen grains within sediment. Evidence of previous rainforest vegetation in a present-day environment may be the result of local or global climate change. Used with other evidence, such conclusions can be confirmed or dismissed iv) Macrofossils: a particular site today may be relatively warm and dry; whereas the remains of particular fauna can suggest earlier wet conditions (such as the megafauna at Riversleigh, Queensland, Australia). Marine molluscs have been used to indicate whether warm or cool fauna existed at a particular time v) Radiometric Dating (or isotopic dating): this type of dating depends upon the radioactive decay of an element, such as Potassium (K) into Argon (Ar) or Uranium (U) into Lead (Pb). The rate of decay of elements is known. Since the 1960s K/Ar dating has been used for dating materials rich in potassium such as basalts; Thorium/Uranium dating is used for dating corals and hence determining rates of sea level change. This method is useful for up to 200,000 years The time interval between the present and the time when the element was fixed can be determined. By determining the age of material a chronology of climate events can be made. vi) Tephrochronology: volcanic eruptions can provide lava and volcanic ash that can act as stratigraphic markers for the Quaternary Period. This marker can be dated via K/Ar. Material above this marker is younger than the marker; material below the marker is older. vii) Deep Sea Cores: these can be dated by such techniques as radiometric or palaeomagnetic methods (see below). Climate-sensitive species can give an indication of temperatures in the oceans at particular times. The shells of some organisms such as Foraminifera coil in different directions. For example, with Globorotalia truncatulinoides left coiling shells indicate cool temperatures; right coiling shells indicate warm temperatures. viii) Oxygen Isotope Method: when ice cores are drilled into ice caps or glaciers the ratio of two oxygen isotopes (160 and 180) within the oxygen bubbles trapped in the ice since the iceâ&#x20AC;&#x2122;s formation can be determined. Low 180 values indicate low temperatures. This method suggests that the last cold phase on Earth started approximately 75,000 years ago and ended about 11,000 years ago ix) Aeolian Sediment: when windblown, sediment can give an indication of past climates. In areas where very fine sediment (typical of glacial till) is found in 32

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vast sand sheets, such as the loess deposits in northern China and Canada, cold dry glacial conditions once prevailed – at least upwind of the site identified. Sediment typical of arid environments has been found in the seas adjacent to continents such as the Tasman Sea. When dated these sediments indicate arid conditions on that part of the continent from which the sediment originated. x) Lacustrine Sediment: evaporites indicate dry conditions in lake areas with minerals such as gypsum and halite forming as a result of high rates of evaporation. Sandy sediments on the edges of former lakes indicate former wet conditions with the formation of ‘beaches.’ xi) Palaeomagnetic Calendar: currently the Earth is said to be in a Normal magnetic field. However, sometimes the Earth’s magnetic field reverses. Sediments consisting of iron minerals record these polarity reversals or Normal and Reversed magnetic fields. A long time scale can be determined with rocks dated as younger or older than these observed reversals.

K/Ar age (year) Millions of years BP

0.7 1

BRUNES (normal) ———— MATUYAMA (reversal)

2 ———— 2.4 3 4

GAUSS (normal) ———— GILBERT (reversal)

xii) Geomorphic/pedologic evidence: fossil sand dunes and landforms such as the now submerged sand dunes on the continental shelf of NW western Australia suggest previously low sea level and arid conditions; glacial cirques in mountain areas suggest previous snowlines and glacial conditions where they may not now exist. The presence of deep weathering soil profiles may suggest previous warm and wet conditions.

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Different types of clouds form depending on the rate of uplift, the rate of cooling, the amount of water vapour in the air, and altitude. Cumulus cloud, Stratus cloud, Cirrus cloud, mist and fog are all examples of cloud (see cirrus, cloud, condensation) cloud seeding — the addition of various substances such as dry ice (solid carbon dioxide), silver iodide and salt into the air (by planes) to act as condensation nuclei in order to increase rainfall. Cloud seeding has been trialled by the CSIRO and is undertaken especially in drier areas coast — that area forming the seaward limit of the land. The coast includes that transition zone between the mainly terrestrial and mainly marine environments. For example the coast, or coastline, includes those coastal forms and processes such as the beach

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(sand, pebbles, mud etc), sea cliffs and sand dunes which show progressively less marine influence and more terrestrial influence the further inland one moves coastal terrain — a landscape dominated by coastal landforms (eg a beach, sea cliff and sand dunes) and coastal processes such as beach and cliff erosion, wind deposition and wave action forming a unique and distinctive suite of landforms (compare this with an arid terrain and a fluvial terrain). Coastal terrains may be dominated by the sweeping zetaform beaches, sand dunes and lagoons; they may be characterised by kilometres of sea cliffs; they may show the dense growth of mangrove communities and broad tidal flats. Like all terrains a coastal terrain is a reflection of the processes and available materials at a particular site (see figure 14)

Figure 13 – Common types of clouds

Source: J Frew, Geographical fieldwork projects, Nelson 1999, p 69

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cohort — a group of people who have a common experience in a period of time. Commonly used when discussing population age groups (based on years of age). For example ‘the 15 years age cohort’, or ‘the 25–29 years cohort’ col — in mountain areas a saddleshaped gap between two mountain peaks (see figure 28) cold front — the boundary between an advancing cold air mass and air ahead of it. The air behind a cold front has very different characteristics than the air ahead of it. Behind a cold front the air is normally cooler and often with higher relative humidity. In Australia, cold fronts approach from the southwest with winds bringing cooler temperatures and sometimes precipitation in the form of rainfall and snow.

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In Australia cold fronts are the result of the interaction between the warmer and drier air coming from the north such as central Australia and the cold sub-polar air from the south. The cold dense air from the south forces the warmer, less dense air of the north to rise. Precipitation often results that is usually more intense but lasts for a shorter time than that of warm fronts (see precipitation and synoptic chart) collective farming — a system of agriculture where the land is farmed by a group of people who work together using shared resources, having shared and allocated tasks in production and sharing of materials produced such as food and any profits. Collective farms can vary in size greatly from small communitybased cooperatives to large-scale

Figure 14 – Coastal Terrain

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communes such as within former Communist China colluvium — deposits of material that have been transported and deposited on a slope as a result of various types of mass movement; for example by water (slopewash) and gravity (slumping) colonialism — a name given to describe the colonisation of one country (often a developing county) by another country (often a developed country) as well as the subsequent political, economic and social control the colonising country has. The term is often used to describe the power of the developed over the developing countries during the 1700s, 1800s and 1900s (see neocolonialism) colony — i) a settlement in a new country by a group of people forming a distinct community. In many ways this colony reflects major characteristics of the country from which the group originated; ii) a group of people with a common heritage forming a distinctive and often isolated group within a wider community column — an example of a speleothem. A column forms as a result of the joining of a stalactite from the ceiling and a stalagmite from the cave floor (see figure 54 colour) columnar basalt — following the extrusion of magma cooling creates long vertical joints with hexagonal cross-sections. After erosion of material around this basalt, vertical towers can be seen such as the Giant’s Causeway, Ireland commensalism — a term used to describe the close association between two different species where there is a benefit to at least one of the species. For example, where an insect lives on cattle and feeds on any parasites on the cattle; where fish in the immediate area of a shark feed on the discarded material of a shark kill; where angelfish and coral share the same habitat (coral providing angelfish protection from predators, angelfish providing food for the coral polyps)

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commercial farming — the growing of crops or the raising of cattle for sale. Examples include in Australia are dairying, where milk is produced for sale to large urban markets, and wheat farming where wheat is sold to local as well as overseas markets commercial grazing — the raising of cattle for sale commodity prices — prices received from the sale of primary products eg crops such as wheat and minerals such as tin common(s) (The Commons) — traditionally this has referred to as an area of land that belongs to the local community rather than one individual person or group and open to be used by all people. More recently, ‘the commons’, or ‘global commons’ has, been recognised where global resources such as the atmosphere, space and the oceans are considered to belong to the global community rather than to an individual commune — a large area of land that is owned and controlled by the community living on it. Communes have been introduced into some communist countries in order to increase food production (such as through collective farming). These large areas of land have been selfgoverning with schools, health services and industry established largely independent of national government. The Chinese communes are an example of this community — a naturally occurring group of organisms occupying a particular environment: i) vegetation – a community is not just a stand of trees but the suite of vegetation species in an area including trees, shrubs, grasses as well as the different species of each (see figure 15 colour); ii) settlement – a group of people with a shared history, beliefs and aspirations. Many communities can be identified on the basis of shared space, religion, ethnicity and socio-economic status commuting — the process whereby people travel long distances to work from their place of residence


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competence — the ability of a stream to transport its sediment load. The higher the velocity (or energy) of the stream the greater the competence and so the greater the load that it can carry composite volcano — a large volcano built by the extrusion of alternating large deposits of ash and lava (see shield volcano) concentric zone model — this model of the internal structure of cities was proposed by E.W. Burgess attempting to explain land use patterns with increasing distance from a city centre (Figure 58). The location of particular land use activities will be influenced by their economic return and their ability to pay (or bid) for a piece land. Assuming an isotropic surface concentric land use zones surround the city. The model, although not close to reality for most urban areas, can be used to explain the location of some land use types. Recognising variations in the biophysical environment, government policies and human behaviour some understanding of spatial distribution of economic activity in urban areas can be achieved (see Burgess, E.W., multiple nuclei model, sector model, figure 58)

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concept diagram — a summary diagram where the main idea (or concept) is highlighted, often in the centre of the diagram, with a number of subtopics or related ideas identified and placed around it. For example in addressing population (as the key concept) related ideas such as population growth, urban sprawl, age structure, rural-urban differences and housing may be drawn with lines linking the main topic and the subtopics. In this way an ordered understanding and a structured presentation of an issue can be made condensation — the process describing the physical change of water vapour from a gas to a liquid. Condensation occurs when the air has become saturated (where relative humidity exceeds 100%). When the relative humidity of the air is 90% condensation does not occur. When the air is cooled further 100% relative humidity may be reached and condensation may occur in the form of cloud, mist or fog. Further cooling may see precipitation in the form of rainfall from clouds or even dew from fog or mist condensation nuclei — particles in the atmosphere such as dust and pollen

Dimensions of Continents

Source: With modifications from Jeans D. (ed) Australia: a Geography, Sydney University Press, 1976

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ENVIRONMENTAL SOCIAL Land degradation Indigenous Peoples Water Quality Population Growth Industrial Trade Waste Refugees Urban Effluent Tourism Greenhouse Recreation Resources Ozone Depletion Amenity Deforestation Community Special Technology Loss of Wetlands Interest Groups Photochemical Smog Ethnic concerns Land/water Disease Species Loss Sahel, Sydney, Los Angeles Synfuels, Chernobyl Indonesia, Sth Pacific Indochina, Highlands Islands, East Africa Central America

ECONOMIC Rates of Use Employment International Debt Economic Growth vs Development Cost-Benefit Analysis Land use Conflict Economic vs Opportunity Costs Environmental Quality Middle East, Malaysia, Debt for Nature Swaps

POLITICAL International Treaties Political Blocs Development of Infrastructure 'Dams vs Habitat' Control of International Waters

The New Geography Dictionary Green Politics State's Rights Political Tensions Philippines, OPEC, LAFTA, Mekong Dams

Papua

New

SE NSW Forests,

Sewage Disposal Infrastructure vs Eutrophication

Guinea

Filtration

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Solar energy Water

TECHNOLOGICAL Alternatives Application of Technology Change over time Renewable vs Non-Renewable

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(various concerns people have concerning water)

I S S U E S

Issues relating to water are largely the result of conflicting and competing perceptions and priorities of water as a natural resource. These manifest themselves as local to international issues affecting environments, individuals and communities. They are all interrelated with common goals of improving environmental quality and the quality of life of people through ecologically sustainable practices. As with all issues there is a spatial dimension which needs to be addressed â&#x20AC;&#x201C; ie the issue occurs at a place and has environmental as well as social consequences.

Figure 16 â&#x20AC;&#x201C; Water: a contemporary geographic issue

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around which water vapour condenses to form water droplets. It does not matter how much water vapour is in the air, if there is no condensation nuclei condensation will not occur; rainfall will be non-existent. The lack of condensation nuclei can lead to prolonged droughts (see cloud seeding) conduction — heating as a result of direct contact. For example the heating of the atmosphere by direct contact with the land Conference for Sustainable Development — following on from the Rio Conference (Earth Summit) and the Kyoto Conference the CSD was held in Johannesburg in 2002 addressing the need to improve the quality of life of people especially in developing countries confluence — the point where to rivers meet to merge as one — eg where the Darling River meets the Murray River at Wentworth, NSW, Australia conglomerate — a type of sedimentary rock; a rock formed from the weathered and eroded fragments of other rocks. Unlike other sedimentary rocks of relatively uniform grain size

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conglomerate rocks usually consist of a mixture of larger and smaller sediment conifer — a cone-bearing tree such as a pine tree. Conifers grow well in cooler climates such as in northern North America and Scandinavia in Europe conservation — a management strategy to maintain the quality of an area through its controlled use following an environmental ethic. This is very different from preservation which has the philosophy of excluding all human activity in order to maintain an area such as a forest in its pristine or natural state conservation tillage — farming carried out with the objective to reduce various types of land degradation such as soil erosion by retaining the stubble (stalks) of harvested crops. Water is able to infiltrate into and be retained by the soil consumers — a term used in the study of ecosystems, used to refer to those organisms that do not produce their own food (such as plants) but consume (eat) plants and/or other animals to gain food and energy. In ecosystems these are the herbivores,

Figure 17 – Plate Tectonics and Continental Drift

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carnivores and omnivores. The term also applies to those people or groups that use (or consume) goods and services — such as natural resources contemporary geographic issue — something of concern in the local, national or global community about which there are spatial implications (Figure 16). In the world today, the quality of the environment is considered to be a CGI because it is of a concern to people around the world but also at the local community level. Urban poverty is a CGI because many people are concerned about the inequalities of income in communities and the social problems that can arise from this. This is a CGI because it occurs at a place and is of concern to people local and global levels. There are many CGIs in the natural and human environments. Look at some of the CGIs that can arise as a result of water use (eg water supply, water quality, flooding, irrigation and recreation) (see figure 16) continent — a very large body of land. There are seven — Africa, Europe, Asia, Australia, Antarctica, North America, South America. There is no specific upper or lower limit as to the size of a continent. However, the smallest continent is Australia at 7.8 million km2 (including Tasmania) while Greenland is the largest island at 2.1 million km2. The continents make up more than 98% of all land. Continents extend beyond the continental shelf. The table on the previous page shows various continental indicators. Strictly speaking Europe and Asia are in fact the one continent called Eurasia (the name ‘Europe’ created in the 1700s) continental climate — a term used to describe the conditions as one moves further inland away from the coast. A continental climate has a variety of characteristics • low total annual precipitation • large annual temperature ranges (ie hot summers, cold winters) and

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• large diurnal temperature ranges (see maritime climate). Central Asia has an extreme continental climate with annual temperature ranges being over 50°C and the large distances from the sea leading to annual rainfall figures of less than 100 mm per annum in Far Western China continental crust — the upper part of the Earth’s surface consisting of the continents. Continental crust is about 20 km deep – much thicker than oceanic crust (see sial) continental drift — the process whereby the continents drift across the surface of the Earth. Continental rocks (see sima) being less dense than oceanic rocks (see sial) rise above the ocean floor moving across the crust of the Earth (Figure 17). More than 200 million years ago all present-day land made up one landmass called Pangaea. This super continent then split into a northern landmass called Laurasia and a southern landmass called Gondwana. The southern continents then split apart; Australia separating from what is now Antarctica about 55 million year ago. Australia is drifting north at a rate of 7 cm a year. The mechanism for the movement of continents and the plates on which they ‘ride’ has been confirmed with the acceptance of plate tectonics continental island — an island that is near a continent but is linked to that continent geologically. In almost all cases these islands are separated from the mainland by an arm of the ocean or shallow sea (such as Sri Lanka, Japan and the British Isles) continentality — refers to the effect of distance from the sea on the climate experienced by a place on the Earth. An area located close to the sea is said to have a much more maritime climate whereas a place located much more inland is said to have a continental climate. Places experiencing a continental climate have the following


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characteristics compared with those of a maritime climate: • lower average annual rainfall total • greater annual temperature range • greater diurnal temperature range Places with continental climates include inland Australia and inland North America. The reason for these

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climates include: • inland areas are further away from rain bearing winds near the coast • the land heats up much more quickly and loses its heat much more quickly than the sea. As a result, more coastal locations are cooled in summer and warmed in winter, whereas more inland areas

Figure 18 – Examples of correlation Correlation is a measure of the relationship between one variable and another. Where one variable and another increases there is said to be a positive correlation (eg in Graph 1 the number of road accidents increases as the number of cars increase). Where one variable increases and the other tends to decrease, there is said to be a negative correlation (eg in Graph 2 the number of species tends to increase as the number of forests cleared decrease) – see Box

Correlation gives an indication of whether a trend can be seen in two sets of data; as variables in one set of data increase the variables in the other set of data may increase or decrease – there may be no relationship at all. However just because there is a positive or negative correlation between two sets of data, this does not mean that one item causes the other; where such a conclusion is drawn from two unrelated sets of data, this is called a spurious (or false) correlation – there may be, and usually are, other factors involved.

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heat up very quickly during summer and during the day; and cool down very quickly during winter and at night continental shelf — the area of low gradient around the continents submerged by the sea. Beyond this lie the greater depths of the ocean such as the deep ocean floor contour interval — the vertical interval in the height of the land as indicated by the different contour values; eg contour values of 10 metres, 20 metres, 30 metres indicate a contour interval of 10 metres contour line — a line joining places of equal height above sea level contour map — a map, using contour lines, showing the height of the land over a particular area contract farming — a type of farming where individual farmers and agribusiness companies are contracted to supply food such as vegetables and meat to large food companies and/or supermarkets contrail — the name given to the condensation trail left be aircraft as a result of water vapour condensing behind the aircraft at high altitude conurbation — the continuous built-up urban area, the result of the merging of two or more urban centres (for example the Tokyo–Yokohama conurbation) conurbanisation — the process of the merging of two or more previously independent urban centres. In eastern Australia the continuous urban sprawl of Sydney and Newcastle may see the merging of these two urban areas into a conurbation convection — the upward movement of material, such as air, as a result of heating from below. On the Earth the land tends to heat up relatively quickly. As it does the air is heated and so becomes less dense than the air above it. The lower air rises in what is called a convection current and may produce rainfall (see convectional rainfall)

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convectional rainfall — rainfall that results from air being heated by the sun, then rising, cooling and eventually producing precipitation. Convectional rainfall commonly occurs in the low latitudes between 0° and 20° north and south of the equator. However it also occurs where any localised heating of the ground occurs such as during summer in the midlatitudes (see frontal rainfall, orographic rainfall, figure 50) Convention on the Conservation of Antarctic Marine Living Resources — a convention or agreement signed in 1982 to protect living resources such as krill and whales from overfishing in Antarctic waters. The primary aim of the convention (signed by Australia) is to ensure the long-term viability of these resources in this fragile environment Copernicus, Nicholaus — a Polish cleric, he confirmed the hypothesis of Aristarcus (1800 years earlier) that the Sun is the centre of our solar system and that all planets rotate around the Sun coral — material formed from the hard outer skeletons of animals called coral polyps coral cay — see Cay corcas — salt marshes along the banks of rivers cordillera — a series of mountain ranges consisting of near parallel ridges and plateaus – for example the large and continuous mountain chains of the Andes and Rocky Mountains Coriolis force — the apparent deflection of a body moving over a rotating surface. The Earth rotates from west to east. In the Southern Hemisphere as air moves north or south the air appears to be deflected to the LEFT; in the Northern Hemisphere the air appears to be deflected to the RIGHT. In the Southern Hemisphere the Coriolis force effect leads to winds blowing anticlockwise around a high pressure cell and clockwise around a low pressure cell (and vice versa in the Northern Hemisphere)


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corporatisation — the transformation of a state owned enterprise or agency into a legal entity subject to company law, including formal separation of ownership and management responsibility, for example through a board of directors or other body corrasion — the wearing away of rock by smaller rock particles; a type of physical weathering correlation — a statistical term which provides a measure of the degree to which two or more features are related (Figure 18). A positive correlation exists where as one variable increases another variable increases. A negative correlation exists where as one variable increases another variable decreases. Where there appears to be no relationship there is said to be zero correlation. However, whether there is a correlation or not between variables, there is not necessarily any causal relationship between the two variables. For example, over the past decade incomes have increased and the number of frog species that have become extinct has increased (a positive correlation). This does not mean that frog extinction has increased because of rising incomes corrie — see cirque cottage industry — where people produce goods for sale but typically work in their own homes and use their own equipment. Goods are normally, but not always, sold locally. Often goods are sold to a retail outlet for distribution. Cottage industries include some clothes production, pottery and supply of artwork counterurbanisation — this represents a net gain in migration down the urban hierarchy. It is not essentially a return to rural areas but rather a movement to the coast or regional centres away from the major urban metropolitan centre. Since the 1980s there has been a return to rural/regional areas from urban areas because of greater crime,

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pollution and congestion in the cities and a perceived improved lifestyle in rural areas; counterurbanistion is common in developed countries. Exurbanisation is a related movement but in this case people settle outside the outer suburban regions of the metropolitan area either in small towns or rural areas country — an independent state whose sovereignty and right to selfgovernment is recognised by other nations coupe — an area of forest to be harvested in one operation eg an area of 200 hectares craton — a very large area of the Earth’s surface that has remained geologically stable for hundreds of millions of years. Mountain building has not occurred since Precambrian times. These relatively flat ancient rocks form the core of major continental areas such as the Western Shield in Western Australia and the eastern part of Canada Cretaceous Period — a period of geologic time 144–66.4 million years ago (see figure 27) crevasse — a deep chasm or gap within a glacier croft — a small parcel of land (up to 2 hectares) used for the growing of crops with an adjoining residence in the Highlands of Scotland cross section — a graph that shows the shape of the land usually drawn from the contours of a topographic map crude birth rate — the number of births measured against the total population. The CBR is commonly expressed as the number of births per thousand people in the total population crude death rate — the number of deaths measured against the total population. The CDR is commonly expressed as the number of deaths per thousand people in the total population (see Infant Mortality rate) cryosphere — the area of the Earth’s surface permanently frozen eg the ice caps of Antarctica and Greenland

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cryophyte — a plant adapted to living in areas of snow or permanent ice cuesta — a ridge with one long gentle slope and a much shorter steeper slope. These ridges are much different from the more symmetrical slopes of ridges in the Eastern Highlands, Australia. Cuestas can be seen in areas such as the Grampian Ranges in southwest Victoria, Australia cultivation — the preparation of the land and the growing and harvesting of crops (eg wheat cultivation) cultural capital — people’s acquired knowledge and skills that are increasingly used in order to gain economic wealth cultural globalisation — globalisation in the for of increased migration, tourism and telecommunications. Globalisation has much more than economic and political implications. It also allows for increasing intercultural exchanges associated with with 'a shrinking world cultural landscape — a term used to describe those parts of the environment that have been significantly modified by human activity; this contrasts with the natural landscape

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culture — a set of common behaviour patterns exhibited by a group current bedding — layers formed as a result of the accumulation of sediment in water such as in a stream or the ocean. Current bedding can be seen on the bed of streams in the form of ripple marks and in near shore areas such as in larger sandbars. The thin layers produced are often less than a millimetre and can give both direction and velocity of flow cusp — a coastal feature; a crescentshaped depression on the seaward facing side of a sandy beach (see figure 14) cyanobacteria — also known as bluegreen algae cyberbia — human society living in an information based, electronic world cyberspace — the area in which all cybernetic (computer) data are stored cycle of erosion — see Davis, William Morris cyclone — an area of low pressure. A tropical cyclone is a very intense area of low pressure occurring in the tropics

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new geography dictionary geography dictionary new dictionary new geography

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Darwin, Charles — in 1859 Charles Darwin published ‘On the Origin of Species by means of Natural Selection’ launching the theory of organic evolution and changing the world and the way it thinks database — an ordered collection of data – such as a computer database datum — any feature or quantity that acts as a reference point from which other features are measured. Sea level can be considered the datum from which altitude is measured Davis, William Morris — a geologist/geomorphologist W.M. Davis provided a new method to describe and explain the surface features of the Earth at the dawn of the 20th century. He identified a ‘geomorphic cycle’ – a process of landscape evolution progressing from the rugged mountains of youth, to the rounded forms of maturity, to the worn-down plains of old age. What became known as ‘the cycle of erosion’ was initially proposed for humid terrains but eventually gained acceptance for a wide variety of landscapes. However ‘the cycle of erosion’ hindered much geomorphic research and such a synthesising model of landscape evolution stalled much research and understanding of the land. Field studies and more empirical research have enhanced our knowledge of Earth surface processes and landscape evolution Dead Sea — located adjacent to Jordan, Israel and Palestine, at 398 metres below sea level, this is the lowest point

on the Earth’s surface. Salinity levels are up to ten times that of the oceans debt for nature swaps — where a low income country agrees to protect a designated area in return for part of its foreign debt being paid by an agency or organisation from a richer country deciduous — a term used to describe trees that lose their leaves in a particular season. In cool environments such as occurs in autumn and winter, in more alpine areas and in areas of higher latitudes, it is common for particular tree species to lose their leaves when temperatures fall. The alpine areas of the Snowy Mountains in NSW, Australia, and the higher latitudes of Tasmania, Australia as well as Canada and countries of Europe are all dominated by deciduous vegetation (see evergreen) decile — a statistical term referring to the tenth part in a ranked array of data. For example in ranked data the first ten values are considered to be in the first or top decile, the next ten values are considered to be in the second or next decile deflation — the process describing material removed from the surface by wind; another term for wind erosion defoliant — a herbicide used to remove the leaves of trees and shrubs and to kill various types of vegetation. Examples of defoliants are 2,4-D and 2.4.5-T a weed killer to control woody weeds and regrowth after clearing deforestation — the clearing of vegetation on a large-scale. Around the world, forests are being cleared to accommodate urban sprawl, agriculture as well as to repay foreign debt.

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Deforestation is most severe in rainforest areas such as in Southeast Asia where over 300 million hectares of land are degraded as a result of deforestation. The Amazon Basin and the forests of Indonesia account for approximately 50% of global deforestation degradation — i) the wearing away or lowering of the surface of the land. Degradation can occur as a result of erosive power of water, ice or wind. The continents are being eroded or degraded by approximately two centimetres per year; ii) the reduction or deterioration in the quality of the Earth’s surface. Degradation can be seen in the deteriorating quality of the land due to soil salinity, and accelerated soil erosion

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deindustrialisation — a process to describe the decline in the importance of manufacturing sector within the economy. Characteristics of countries undergoing deindustrialisation include a decline in the number and percentage of the total workforce employed in manufacturing, a decline in manufacturing output and a decline in the number of manufacturing enterprises. Deindustrialisation has occurred in Australia, for example, with the decline in steel production in Newcastle and Wollongong and the decline in the car industry in South Australia. Many areas undergoing deindustrialisation have high unemployment and see shifts in the type of work undertaken by the workforce. Many

Figure 19 – Delta system

Source: E.C.F. Bird, Coasts, Second Edition, Australian National University Press, 1976, p 207

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areas see a shift in the workplace concentrating on the service sector delta — a cone-shaped landform formed from the deposition of sediment in a body of water (Figure 19). A stream will flow downstream carrying its load of sediment. As the velocity of the stream slows down as it approaches and meets the sea, the stream deposits it load. It does this because it no longer has the energy to carry so much sediment. The landform that results from this deposition is a delta – this name because it resembles the shape of the Greek letter delta demographic change — the change in the characteristics of a population such as population numbers, age and sex structure and growth rates. Identifying change in population characteristics is useful in predicting future population patterns and structure allowing for long-term planning by government and nongovernment organisations (such as analysing census data) demographic transition model — a model used by population geographers to describe and explain the changing birth and death rates over time. Initial populations are fairly stable with high birth and high death rates. However, over time as the population expands, death rates slow down followed by declining birth rates. Low birth and death rates later coincide with populations that grow relatively slowly. As populations grow in developed countries, declining birth rates occur for reasons such as lower death rates following improved health care and birth control demography — the study of population. In particular the manipulation of statistical data to identify patterns and trends in population data. Demographers analyse this data, not only to describe populations but to also make predictions as to population

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trends and to provide data for community planning decisions dendritic — a term used for a river drainage pattern where many smaller rivers, of tributaries, flow into a larger river. It may be seen as a tree-like pattern (see figure 22) dendrochronology — a branch of study that uses the analysis of tree rings as a dating technique as well as a strategy to understand earlier climatic conditions. For example widely spaced tree rings tend to indicate favourable growing conditions, a faster growing cycle, and therefore wetter conditions. More closely spaced tree rings indicate less favourable growing conditions such as drought or even cooler conditions (see figure 12) denitrification — the process whereby nitrogen is removed from the soil having been converted into a gas. The nitrogen would otherwise have been used as a nutrient for plants dense — closely spaced. For example, a dense settlement has a lot of buildings in a small area (see sparse) density — the number of features in an area for example “a density of 5 buildings per km2 means that there are on average 5 buildings in a square kilometre” (5 per square kilometre) deposition — the accumulation of sediment by the action of agents such as water and wind. Water can deposit sediment to build landforms such as deltas; wind can deposit sediment, such as sand, to build sand dunes depositional site — in the study of soil materials these are areas such as river floodplains and coastal sand dunes where the dominant process is that of deposition by wind or water or gravity. The soils have a typically uniformly coarse or uniformly fine texture with little pedal development. Soils formed in depositional sites include podsols within dune sands as well as alluvial soils along river flats (see residual site and transportational site)

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depreciation — the reduction in the value of an asset as a result of its use. This is often expressed as a percentage per year. For example machinery may depreciate in value 10% per year as a result of its use over time depression — an area of relatively low atmospheric (air) pressure (also called a low) desert — an area where permanent vegetation cannot be supported because of one or more of a number of factors eg annual precipitation may be too low or soils may be very poor in nutrients (see figure 20). There are hot deserts such as the Sahara Desert in Africa and the Great Sandy Desert in Australia. There are also cold deserts such as the Antarctic continent – the driest continent on Earth. In both cases, average annual precipitation is very low. Beaches are also considered deserts because the

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nutrient poor environment prevents much vegetation growth desert varnish — a thin coating on rock surfaces in arid environments. The coating, often less than a millimetre in thickness, is made up of varying combinations of silicate clays and iron and manganese oxides desertification — the intensification or spread of arid conditions. The process of desertification can occur in already arid or desert areas where average rainfall declines over time. For example the Great Sandy and Simpson deserts of central Australia may become even drier than they are today (desertification is occurring, arid conditions are more intense). Desertification can also occur as arid conditions extend over a larger area. For example over time western New South Wales becomes drier than normal; the desert appears to be expanding.

Figure 20 – Arid Terrain

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The process of desertification has been blamed on natural climatic conditions; for example high pressure cells become more intense and hence drier in the mid-latitudes. Desertification has also been blamed on human activity in semi-arid areas around the world; for example clearing of woodland in marginal areas and the movement of refugees and associated population pressures that follow. Desertification has led to the loss of much land around the world both for agricultural production as well as that being available for settlement. East Africa, southwest USA and western NSW and Queensland have been subject to desertification dessication — the process of drying out; often used when referring to arid or semi-arid environments detritus — decomposing plant and animal material, such as leaf litter detritivore — an animal that feeds on dead and decaying plant and animal matter (eg in leaf litter on the forest floor) developing country — a term used for a country with relatively poor quality of life as shown by various socioeconomic indicators such as inadequate housing, very low incomes per head of the population, disease, and low life expectancy. Developing countries in Southeast Asia, Central and South America, and Africa tend also to show poor levels of environmental quality such as poor drinking water development — a process of positive change with social, economic, environmental and personal wellbeing improving over time. Development is a dynamic process proceeding at different and uneven rates from local to global scales Devils Lair — a cave in southwest Western Australia with evidence of animal bone dating back more than 30,000 years (70–2040 individual animals per square metre).

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There is the suggestion that this may be a ‘kill site’ with evidence of tools such as split pointed bone (shaped by people) dating at 29,500 years old – an important archaeological site Devils Marbles — located in the Northern Territory, Australia these are piles of rounded granite boulders up to three metres diameter surrounded by an extensive eroded flat plain. Aborigines see them as the eggs of the ‘Rainbow Serpent’ dew point — the temperature at which the air becomes saturated with water vapour (or relative humidity reaches 100%). Below this temperature condensation occurs and dew forms diastrophism — tectonic processes within the Earth leading to processes such as mountain building, faulting and folding. As plates collide, such as the Indian Plate with the Asian Plate, mountains such as the fold mountains of the Himalayas are formed; as plates move strains are placed on the Earth’s crust leading to faults such as those of the Great Rift Valley in East Africa and the San Andreas Fault of North America. These are the result of diastrophism diatreme — a general term used for the vents through sedimentary strata caused by volcanic activity dieback — a process leading to the widespread death of trees. Dieback is seen as trees prematurely losing their leaves. The trees start to dieback from the tips of leaves and shoots, eventually along longer stems and finally the whole tree. A large area of defoliated trees may be evidence of dieback. The eucalypts (gum trees) of the northern and southern tablelands of NSW as well as the southwest forests of Western Australia are severely affected by dieback. The cause of dieback is not known. It has been attributed to various causes that include the: • short-term climate change such as the drought in eastern Australia

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during the 1980s from which certain tree species have not been able to recover • age of such species reaching a point whereby the species is no longer viable — considering the widespread loss of both similar species and species of similar ages • large-scale clearing of surrounding land altering water balances and associated biophysical processes • selective removal of other species following land clearing which, in the past, provided mutual protection from the invasion of pests and disease These are only assertions; the cause or causes may lie elsewhere diffusion — the spread or movement of a feature, such as population, away

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from a point such as a city or throughout the rural hinterland. Diffusion includes the movement of people and the spread of settlement over an area but it also includes the transmission of information by word of mouth as well as electronically such as via the media and the Internet dike — see dyke Diprotodon — the world’s largest (extinct) mammal — part of Australia’s extinct megafauna 75,000 years ago. These were browsers of plants built like a wombat but the size of a rhinoceros – an adult weighed up to two tonnes discharge — the amount (or volume) of water flowing in a river over a particular period of time.

Figure 22 – Examples of drainage patterns

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For example the Amazon River has a discharge of approximately 5600 km3 of water per year; the Nile approximately 90 km3. Discharge of local rivers is often expressed as cubic metres per second dispersed — spread out; as in a dispersed population dissected plateau — a once large and extensive plateau that has been eroded by rivers forming deep and often steep river valleys in its surface (figure 21 colour). The surface of the plateau is marked by the interfluves of these rivers. The similar height of these interfluves indicates that the land was previously a relatively flat or level surface dissolved oxygen — oxygen molecules that are dissolved in water. Dissolved oxygen is important to aquatic life. The dissolved oxygen content of water is higher in flowing water as there is a constant interaction and mixing between the atmosphere and the water. Low values are recorded following outbreaks of algae as they use up oxygen (this poses a threat to marine and river life). The very still and deep waters behind the walls of dams have little or no dissolved oxygen. These areas are sometimes known as aquatic deserts because very little life exists distribution — the spread of features over an area; they may be spread out (sparsely distributed) or very close together (dense) (see dispersed, sparse) diurnal — relating to the differences between day and night (rather than relating to a year) diurnal temperature range — the difference between the maximum daytime and minimum night-time temperatures (see annual temperature range, temperature range) diversification — i) a process where, for example, a business expands into a different line of business. Instead of a car manufacturer expanding by buying

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up other car manufacturing businesses the business might expand by purchasing or establishing an Internet company; ii) evidence of the greater variety of plant and animals in an area such as a rainforest biome – as in a diversified ecosystem division of labour — a term used to describe the specialisation of labour (or the workforce) into specific parts of the production process. A single worker or group of workers may specialise in one aspect of production. This division of labour is common in the agricultural, industrial and service sectors of he economy. It has the effect of utilising the specific skills of individuals but can also lead to individuals gaining greater skills in specific tasks in which they are engaged DNA — deoxyribonucleic acid doldrums — an area on the Earth’s surface between 5°N and 5°S latitude. In this area the variable winds are very light because the pressure gradient is so small and the coriolis effect is negligible doline — a funnel-shaped sinkhole where a surface depression leads to surface waters flowing rapidly into the hole beneath the surface (typical of karst topography) doughnut effect — the loss of population and urban services from the city centre to the city outskirts dormitory — an area where people sleep (eg a dormitory suburb is one where people live but travel to another suburb to work) drainage — i) the runoff of water from an area by streams; ii) the use of artificial pipes to drain excess water from the land drainage basin — see catchment area drainage pattern — as a result of water flowing in channels across the land it is possible to recognise a pattern that the streams make (see figure 22). The New Geography Dictionary

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Types of drainage patterns include: annular, barbed, dendritic, parallel, pinnate, rectangular, radial and trellis. These drainage patterns give an idea of the type of land through which the stream is passing drainage system — the main river channel and all of its tributaries; this drainage system exists within a drainage basin and can form a distinctive drainage pattern Dreamtime — the ancient time referred to by the Australian Aborigines of the creation of all things. ‘The Dreaming’ refers to the spiritual beliefs of Australian Aboriginal people dreikanter — a stone found on the surface of desert areas with marks characteristic of wind abrasion drip irrigation — the irrigation of individual plants by the use of a piping system feeding water directly to the roots of plants (this is very different to spray irrigation) drumlin — a smooth mound of material deposited by a glacier and elongated in the direction of previous glacial movement dryland salinity — a type of secondary salinity. Under normal conditions the water table is kept below the surface as a result of deep-rooted plants taking up moisture. The clearing of these trees destroys the root systems and so allows the water table to slowly rise up to the surface. Water evaporates leaving a thin film of salt crystals on the surface. Very little can grow on this saline (or salty) bare surface. The erosive action of wind and water makes the land affected by dryland salinity useless for activities such as agriculture. Dryland salinity is a very serious problem in not only Australia but worldwide (see irrigation salinity) dual economy — where two economies exist in the same area such as in a city. In many newly colonised countries the traditional (indigenous) economy

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exists side by side with the new introduced economy with very little contact between the two dual occupancy — an example of urban consolidation that has the advantage of allowing relatives to live with their families but in separate dwellings. There is also the advantage of providing for additional rental accommodation for people who cannot afford their own home. Problems associated with this include increasing pressure on community infrastructure such as water supply, neighbourhood traffic congestion and recreational amenity dune — a landform composed primarily of sand having been deposited by wind or water. In arid environments, such as in deserts or even the back of beaches, large deposits of sand occur as a result deposition by wind – (see seif dune and barchan dunes in deserts and frontal dune and foredune on beaches) dune stabilisation — the prevention of sand dune erosion by a variety of techniques. These include planting of vegetation providing roots to bind the sand together. Eventually the dune will be colonised by deeper-rooted plants such as trees duplex soil — a soil characterised by a texture contrast between the A- and Bhorizons. Typically a coarse sandy /sandy loam overlies a finer clay/clay loam. The boundaries between the A- and Bhorizons are clear to sharp. The distance between the bottom of the A- to the top of the B-horizon is less than 10 cm. In many instances the duplex is the result of both weathering of bedrock in situ (leading to a clayey B-horizon) and surface processes such as slope wash and soil creep (leading to sandy A-horizon) — see also texture contrast soil


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duplex texture — see duplex soil, uniform texture and gradational texture duricrust — the hard surface of the land in some environments that have formed as a result of the cementing of iron or silica minerals. This hard capping protects the surface from various types of erosion. Examples of types of duricrust are silcrete and laterite dust bowl — originally the ‘Dust Bowl’ was an agricultural area in central USA in the 1930s. A long drought saw the natural vegetation die off and when the land was then ploughed again to plant crops the topsoil was lost due to prolonged wind erosion. Less fertile

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subsoil was exposed which was useless for farming. More recently, those areas subjected to widespread wind erosion, leading to very poor quality land, have been referred to as dust bowls dyke — i) an artificial embankment built to prevent the flooding of land; ii) an intrusion of igneous material which cuts across already existing rock structures. In many instances the more resistant dykes can be seen as a landform rising above the general level of the land where less resistant material has been weathered and removed by various processes of erosion eg the Warrumbungle Mountains, NSW Australia

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earthflow — the down slope mass movement of waterlogged earth. A bowl-shaped scar on the land is usually left upslope from which the earth has detached, and a large mound of earth at the toe (bottom) of the earthflow. Earthflows are very common in temperate areas subjected to excessive grazing where the topsoil has been left vulnerable due to loss of a protective vegetation cover earthquake — the result of shock waves passing through the Earth’s crust following movement within the Earth’s crust or upper mantle. The location of initial movement within the crust is called the earthquake’s focus and the point immediately above at the surface is called its epicentre. Earth Summit — an international conference held in Rio de Janeiro (Brazil), June 1992. The objective of the conference (also known as the Rio Conference) was to assess the status of global resources within the atmosphere, the lithosphere, the hydrosphere and the biosphere. Chaired by the then Norwegian Prime Minister, Gro Harlem Brundtland, the conference produced a book called Our Common Future providing an inventory of global natural resources and strategies to ensure their longterm viability (see Rio Declaration) Earth System Science — the study of the integrated physical and social systems that operate on a global scale. Rather than the simplistic study of how people modify the biophysical environment and vice-versa the earth is seen as a single integrated system much like an organism as suggested

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with the Gaia hypothesis. Earth System Science is a major discipline in attempting to understand the functioning of the Earth East Antarctica — that part of the Antarctic continent also known as Peninsula Antarctica. East Antarctica extends along its Pacific Ocean coast from the Ross Ice Shelf at approximately 160ºW longitude through to the Ronne Ice Shelf at approximately 70ºW longitude inland to the South Pole (see West Antarctica) East Asia — that part of Asia comprising China, Taiwan and Mongolia (see South Asia, Southeast Asia and West Asia) Eastern Highlands — a much better descriptive term used than the ‘Great Dividing Range’ in eastern Australia and one increasingly used – because there is no great dividing range along eastern Australia but rather a series of flat to undulating highland areas separated by broad valleys East Pacific Rise — a mountain chain under the eastern part of the Pacific Ocean extending for over 5000 kilometres separating the Pacific plate to the west and the Nazca, Cocos and North American plates to the east (see continental drift, Mid-ocean Ridge, plates) ebb tide — the falling tide (see tides) eclipse — see lunar eclipse; solar eclipse ecological dimension — in studying a particular geographic issue the study includes a consideration of the biophysical environment and in particular relationships been people and the biophysical environment ecological footprint — the hinterland and natural resource base an urban area depends on to sustain its population and economic activity


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ecological sustainability — the use of natural resources of the environment, such as flora, fauna, water and the atmosphere, in such a way and at such a rate as to ensure the long-term availability and quality of this resource. As an environmental resource in its own right this ensures it being available for future generations e-commerce — electronic commerce. Increasingly businesses are using electronic technology to conduct business (eg computers and email) economic development — an unfortunate, misused term not used a great deal today. Previously it was synonymous with economic growth, with development based only on economic indicators such as GDP per capita and income levels. A much better term, that reflects other indicators such as life expectancy and levels of political freedom, is development economic geographer — a person who studies the spatial patterns of economic activity. Themes include urban development, industrial activity and agricultural patterns economic growth — a process of increased output of goods and services (GDP). Usually GDP is expressed as a percentage compared to the previous year. For example ‘Economic Growth has increased by 2%.’ economy of scale — the advantage received from being large. A large company can achieve an economy of scale by producing goods at lower costs as a result of purchasing its raw materials in bulk and so reducing its costs. Economies of scale can lead to goods being produced more cheaply and increasing a company’s profits ecosphere — another name used for the biosphere ecosystem — a community of interacting plants and animals. An ecosystem includes interactions between the biotic (living) parts of an area as well as between these biotic parts and abiotic (non living) parts eg soils, rocks, streams and sunlight

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ecotone — that area which marks a gradual transition between two distinctive plant communities. The ecotone is not a sharp boundary but shows gradual change in features such as soil type, aspect and microclimate as one moves for example from a woodland to a grassland ecotourism — tourism that is based on the appreciation of the natural environment and has, as an important component, education and the understanding of the natural environment. The objective of ecotourism is to ensure ecological sustainability. edge city — an office, entertainment and shopping area that is primarily a work centre rather than a residential suburb. A place that developed to challenge the dominance of the Central Business District ecumene — the inhabited areas of the Earth’s surface edge wave — an oscillatory standing wave produced parallel to the shoreline with crests of waves at right angles to the shoreline. They are common on steeper beaches and strongly influence the location and spacing of rip currents effective precipitation — that part of precipitation that is available for plant growth after water loss from evaporation. Actual precipitation may be 650 mm per year but if evaporation is 400 mm per year then the effective precipitation is only 250 mm Ehrlich, Paul — published the controversial book ‘The Population Bomb’ providing convincing arguments to show that one day the human population on Earth must stop growing at its present rate as such growth is unsustainable EIS — see Environmental Impact Statement Ekman spiral — the swirling or spiral effect of parts of the ocean due to the Coriolis Effect. In the middle of the North Atlantic Ocean ocean currents move in a clockwise direction. As they move the surface layers are The New Geography Dictionary

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deflected to the right. Layers below the surface are dragged in this direction too. However these currents are again deflected to the right. This continues as depth increases. The net effect of this spiral is for the water to be directed to the centre of the spiral and for surface material such as any seaweed to collect there. The Sargasso Sea in the North Atlantic Ocean is a result of the Ekman Spiral El Niño — this occurs along the coasts of Peru and Ecuador in South America (Figure 23). The warm ocean currents along the coast are replaced by cold water from the depths of the Pacific Ocean.

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The name means ‘the Christ Child’ following the fog produced by the cold current and the fact that an El Niño event occurs around the Christmas period every 5–7 years. An El Niño event often leads to areas of higher pressure over Indonesia and northern Australia often leading to widespread drought in eastern Australia (see figure 23, ENSO, La Niña) eluviation — the downward movement of soil particles under the influence of gravity through a soil profile (see illuviation and figure 53) embryo dune — a small, recently formed sand dune found at the back of the beach.

Figure 23 – El Niño/Southern Oscillation (the ENSO Cycle)

Source: J. & M. Gribbin New Scientist, 22 May 1999

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The dune is composed mainly of fine, windblown sand with little or no evidence of recent stabilisation by any colonising grasses. After initial colonisation and eventual stabilisation the embryo dune may eventually develop into a larger foredune emergency aid — see foreign aid emigration — the movement of people out of an area. Emigration can be viewed as: • voluntary emigration such as the movement of people out of one country in search of a better lifestyle, job opportunities or even a family reunion. Such international emigration occurred from European countries to Australia in the 1950s and more recently from areas of Southeast Asia • forced emigration such as people leaving a country because of religious persecution (such as from the Middle East) or political persecution (such as from South Africa) or even environmental degradation (such as from Ethiopia). Such forced emigrants are often called refugees (see immigration)

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enclave — a small area or territory within a larger area or territory. Traditionally this has referred to a small state within another such as Vatican City surrounded by Rome, Italy. Enclaves can also be used to refer to small groups within a city distinguished by features such as a culture, ethnictiy or age, hence ‘ethnic enclave’ endangered species — these are species (plants and animals) that are under threat from the activities of people such as land clearing and poaching. Examples include the Giant Panda (China), the Black Rhinoceros (Tanzania) and the Yellow-footed Rock Wallaby (Australia). The greatest threat to species around the world is due to habitat loss as a result of forest clearance and urban sprawl endemic — occupying a specific region only endemism — belonging exclusively or confined to a particular place endothermic — a term applied where heat or energy is absorbed (such as by an organism) enhanced greenhouse effect — the result of the addition of greenhouse

Some Endangered Species around the World CONTINENT Europe Asia

Australia North America South America Africa

SPECIES Hermit Beetle, Luells’ Sea Anemone, Spanish Lynx, Common Sturgen, Danube Salmon, European Mink Tiger, Wild Yak, Snow Leopard, Indian Elephant, Giant Panda, Chinese Alligator, Amber-coloured Salamander, Taiwan Macaque, Sun Bear, Mudora Crocodile, Black Spotted Cuscuss, Sumatran Rhinoceros, White Cockatoo, Giant Bandicoot, Grey Wolf, Prezewalski’s Horse, Orangutan Mary River Cod, Yellow-footed Rock Wallaby, Northern Hairy-nose Wombat, Black-striped snake, Greater Bilby, Helmeted Honeyeater, Pygmy Possum, Mahogany Glider, Koala Polar Bear, Wooping Crane, Bald Eagle, Gila Trout, North American Bison, Muddy rock Snail, Eastern Couga, Bolson Tortoise Longhaired Spider Monkey, Greybacked Hawk, Indigo Macaw, Maned Sloth, Giant Otter, Giant Armidillo, Jaguar Cuvier’s Gazelle, Cheetah, Pygmy Hippopotomus, Gorilla, Gelada Baboon, Black Rhinoceros, Cave Catfish, African Elephant, Aye Aye (Madagascar), White Rhinoceros

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gases by human activity (see greenhouse effect) ENSO (El Niño – Southern Oscillation) — the changing conditions of the lower atmosphere across the Pacific Ocean. The usually strong easterly trade winds become much weaker during an ENSO event. As a result the atmospheric pressure over the central Pacific Ocean is low and unusually high air pressure occurs over northern Australia. Drought conditions in eastern Australia are then common (see El Niño, figure 23, La Niña, Walker Circulation) environment — the biophysical surroundings and the community in which people live environmental audit — i) an inventory of existing environmental factors such as soils, forest and wildlife; ii) a review of a company’s activities to ensure that it is complying with existing environmental standards as laid down in legislation environmental cost — the result of an activity that reduces environmental quality. The construction of a water supply dam may incur the environmental cost of increased soil erosion in the area and loss of habitat environmental ethic — having a concern for the quality of the natural environment; this environmental ethic influences the actions of people towards the environment and its resources environmental flow — the volume of water required in a river, or wetlands generally, to maintain its quality. In many rivers water has been extracted for irrigation reducing the amount of water in these rivers. This has led to the loss of aquatic life, such as fish and vegetation, and in some cases posing threats to the activities of people such as the river’s use for recreation and as a source of drinking water. This is particularly the case of the Murray River, Australia. Environmental flow in the Murray River is attempting to be restored with government

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regulation restricting the amount of water lost to irrigation farmers environmental impact statement — a document that must be prepared by a company or organisation where a proposed development may have various environmental impacts. Besides giving a brief outline of the proposed development an EIS must outline and assess the positive and negative effects of the proposal, any short- and long-term impacts, as well as any associated local or national scale impacts. An EIS must be undertaken to ensure environmental as well as social implications of a proposal are considered as well as economic and technological considerations. The document must be prepared; however its findings do not have to be implemented environmentalism — a philosophical concept that stresses the importance of the environment in the affairs of people and the need to maintain the quality of the environment to ensure a sustained positive quality of life of all people. Extreme environmentalism is known as environmental determinism whereby it is suggested that key environmental processes determine the activities of people environmental lapse rate — the change in atmospheric temperature with height. Under normal conditions in the atmosphere, where air is not rising, the temperature decreases with height. The ELR varies around the world (between 6–8°C in the troposphere) but the average figure is taken as 6.5°C per kilometre. When air is forced to rise such as by convection, orographic uplift or frontal uplift the lapse rate is much different (see adiabatic lapse rate) ephemeral — short lived i) a plant that flowers after a short period of rain; ii) a stream that flows only during or after a brief period rain


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epicentre — the point on the Earth’s surface directly above where an earthquake originated (focus) deep below the surface. The epicentre of an earthquake is usually where the strongest force of the earthquake is felt epicormic buds — buds under the surface of a tree (usually the trunk of the tree) that sprout after the tree has been damaged by fire epiphyte — a plant that grows on another tree using the tree to anchor itself. An orchid perched high up in a tree’s canopy is an example of an epiphyte. It has attached itself to the tree only to gain sunlight and to collect falling leaf litter and moisture equator — an imaginary line around the Earth (0° latitude) dividing the Earth into two hemispheres. This is properly known as the geographic equator (see heat equator) equifinality — a term used to indicate that despite different initial conditions similar or identical results occur; for example both increasing forest clearance and urban sprawl can lead to the similar end result of species extinction equinox — with the tilt of the Earth at approximately 23½°S the Sun appears to be over the equator on two days each year — 21 March and 22 September. In the Southern Hemisphere 21 March is called the Autumnal Equinox and September the Spring Equinox. At these times the Sun is directly over the equator and all places have 12 hours of daylight and 12 hours of night Eratosthenes — a geographer, philosopher and mathematician 2200 years ago who was the first person to determine the circumference of the Earth — with two wells, the Sun and two sticks. At approximately 40,000 km he was right erg — a large area covered by sand as in parts of the Sahara Desert and the Namib Desert in Africa (see figure 20)

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erosion — the picking up (or entrainment) and removal of material. Erosion is a natural process and is best called normal erosion. Erosion occurs as a result of the action of wind, water, ice or gravity picking up material (erosion) making it available for transport by wind, water, ice or gravity. With the activities of people such as vegetation clearing, agriculture and the construction of roads and buildings, normal erosion is increased; this additional erosion as a result of human activity beyond normal erosion is called accelerated soil erosion. Examples of erosion include soil erosion, such as gully erosion and deflation erratic — a rock (or boulder) that has been transported to its present position by a glacier that no longer exists in the area. Erratics indicate the former presence of glaciers in an area esker — a long sinuous (windy) hill in the form of a sand or gravel ridge deposited by the meltwater at the front, or toe, of a glacier. When identified today in non-glaciated areas eskers indicate the former presence of a glacier; and so give an indication of climate change estate — in agriculture, a large farm covering a large area. In tropical and subtropical areas these are commonly called plantations estivation — a dormant state of some animals in summer in arid environments during long dry periods; a type of adaptation of desert animals (see hibernation) estuary — the wide, lower part of a river where it meets the sea and where it is influenced by the properties of the sea — such as the water being relatively saline (salty) and the water rising and falling with tides. Many rivers in temperate latitudes have wide estuaries where they meet the sea. This is because, during the last ice age, rivers flowed across the exposed continental shelf and cut deep valleys through them.

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When sea level rose these valleys were flooded and became estuaries such as Sydney Harbour, NSW Australia (see figure 25) ethnic cleansing — the annihilation, or forcible removal from a country or region, of one ethnic group by another often more dominant group ethnic minority — a small group of people in a wider community distinctive on the basis of a combination of features such as race, language and history EU — European Union; an organisation comprising 15 countries of Western Europe where cooperation and integration of social, economic and political life is being promoted. One of the main features of the EU is the removal of trade barriers between member countries. The member countries are Spain, Sweden, Greece, Portugal, Finland, Luxembourg, France, the Netherlands, Belgium, Austria, the United Kingdom, Ireland, Germany, Denmark and Italy eucalypt — a tree species commonly referred to as a ‘gum tree.’ Some examples of Eucalypts include Blackbutt (Eucalyptus pilularis), Iron Bark (Eucalyptus paniculata), Red Bloodwood (Eucalyptus gummifera) and Scribbly Gum (Eucalyptus haemastoma) eulittoral zone — the portion of the coastal zone that extends seawards from the high tide mark down to the limit of attached plants (can be as deep as 60 metres)

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eustatic — related to worldwide changes in sea level eutrophication — the nutrientenrichment of water and/or land. There is a natural level of nutrients in water; this is called natural eutrophication. However, when additional nutrients are added as a result of the activities of people, cultural eutrophication occurs. Eutrophication results from sewage outflows into streams; domestic detergents and waste from farm dairies. The addition of phosphorus and nitrogen eutrophies waterways as well as the land. Such eutrophication can lead to algal blooms that can become toxic. In waterways, water loses most dissolved oxygen in breaking down the nutrients and from the photosynthetic process of algae. The water becomes an aquatic desert in which very little life can be supported. In a similar way, land can be eutrophied with nutrient spills and leaks from municipal tips (see leachate). Where these nutrients have spilt and formed part of the surface or groundwater runoff native vegetation invariably dies because it is not adapted to these nutrient rich conditions evaporation — the loss of moisture in its liquid form from the surface of an object to the atmosphere in the form of water vapour (gas) — such as from a lake, river, the ocean or even soil. Water can evaporate off the surface of leaves of plants; but the loss of

Common Weeds in Australia and Preferred Habitat

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Prickly acacia (small tree/shrub)

Mitchell grasslands

Para grass (semi aquatic)

Wetlands and streams

Buffel grass (ground cover)

River banks in semi arid areas

Bitou Bush (small shrub)

Coastal dunes (foredunes, dry heath and littoral rainforest)

Water Hyacinth (aquatic)

Still water surfaces, high in nutrients

Salvinia (aquatic)

Still or slow flowing water bodies, high in nutrients

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moisture from within the plant is known as transpiration. The loss of moisture and the rate of loss of moisture is influenced by a number of factors such as the: • input of energy to heat the water (eg from the Sun) • the character of the surface from which the water is evaporating • slope of the land • type of soil and • the vegetation cover These can significantly affect the rate of evaporation. In more humid climates precipitation exceeds evaporation (P>E); P may be 1200 mm per annum, E may be 500 mm per annum – there is excess water available; that is why rivers flow permanently. However in more arid environments (P<E); any precipitation quickly evaporates. Precipitation may be 400 mm per annum but because of high temperatures there may be the potential to evaporate 750 mm per annum. In these areas there is the potential to evaporate much more water than is available. In arid environments, such as central Australia, potential evaporation is high (see evapotranspiration) evaporite — a mineral that has been dissolved in water and has precipitated out to form a rock compound of these minerals especially in hot arid areas — in the same way as salt crystallises when sea water evaporates on a rock platform on the coast. Sodium Chloride (common table salt) is an evaporite as is Calcium Sulphate (gypsum) evapotranspiration — a major process in the hydrologic cycle in transferring water from one place to another. Evapotranspiration is the combined loss of moisture from the earth – from the land and water surfaces such as the oceans and lakes (evaporation) and from vegetation (transpiration)

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evergreen — a term used for trees that retain their leaves all year round. Evergreen trees typically occur in relatively warm, moist areas; for example at low elevations in temperate climates and in relatively low latitudes where temperature ranges tend to be small exfoliation — a type of physical weathering where the outer layers of rocks such as boulders peal off like the layers of an onion. This is also called onion skin weathering. Stresses are caused in the outer layers of the rock as a result of either heating and cooling or the outer layers being subject to continuous wetting and drying exosphere — the outer most layer of the Earth’s atmosphere exothermic — a term applied where heat or energy is released (such as by an organism) exotic — not native to an area. Exotic plant and animal species have often been introduced from another area such as from overseas. Examples include the Cane Toad and the rabbit, and weeds Lantana and Patersons Curse exotic river — a river in a relatively arid area that receives its water from another area usually more humid. The Nile River in Egypt is an exotic river; it flows northward through the deserts of Sudan and Egypt after receiving its water form the wetter equatorial areas of Uganda and the highlands of Ethiopia expatriot — a person who decides to live or work away from his/her native country. Expatriot Australians in New Guinea, for example, are those people who choose to live or work in New Guinea after being born or living most of their life in Australia exponential rate — increasing at an increasing rate; for example increasing at 5% over a 10 year period, then 9% over the next 10 year period, then 20% over the next 10 year period. This is very different from an arithmetic

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increase where the rate of increase in constant over the periods indicated extensive farming/agriculture/land use – farming carried out on very large areas of land such as wheat farming and beef cattle grazing. Extensive farming is carried out because small areas of land are not economic to farm (see intensive farming) extrusion — the name given for the process of magma reaching the surface and flowing out across the land’s surface as lava. Rocks that have formed from the solidification of lava (eg Basalt) are called extrusive rocks (see intrusion)

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exurban — an area beyond the built-up area of an urban centre such as a city; for example settlements dominated by hobby farms on the outskirts of a city blur the boundary between rural and urban areas (also Exurb) exurbanisation — the growth of settlements beyond the official limits of a city but still linked to the city in terms of transport, employment and the service provision (eg hobby farms) eye — the centre of a tropical cyclone where air descends from the upper atmosphere filling the low pressure system — a calm area around which cyclonic winds blow

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new geography dictionary geography dictionary new dictionary new geography

F

fabric — the organisation of soil particles within soil material. A soil can be described as having a pedal fabric where soil particles are arranged in natural soil aggregates called peds (see apedal) fabricating — see manufacturing factory farming — raising animals in an artificial environment. In the production of chickens, eggs and pork, for example, animals are restrained in a confined environment and fed a controlled diet. The buildings in which these animals are housed as well as the procedures undertaken in food production resemble that of small factories. There is community concern as to the ethics associated with this type of food production faecal coliform — bacteria derived from the faeces of humans and other warm-blooded animals (Figure 24). These bacteria enter waterways from agricultural and stormwater runoff as well as sewage discharge into waterways. Faecal coliform bacteria are not pathogenic (ie they do not cause illness or disease). Rather they occur with pathogenic organisms; so they act

as an indicator that pathogens may be present. Disease such as typhoid, hepatitis and gastroenteritis can occur with high faecal coliform counts fahrenheit scale — a temperature scale used where the freezing point of water is 32ºF and the boiling point of water is 212ºF. To convert Fahrenheit temperatures to Celsius see the ‘conversions’ section in the Appendix of this dictionary fallow — a term used to describe land that has been left unused so as to regain its fertility while other land may be given over to crops FAO — Food and Agriculture Organisation (a United Nations organisation) fathom — a measure of water depth equal to six feet in imperial measure fault — a fracture or fractures in the Earth’s crust across which can be seen relative displacement of the same rock unit fauna — an alternative term for animals (see flora) Favelas — squatter settlements surrounding Rio de Janeiro, Brazil federation — when Australia was declared a nation on the 1st January 1901. The first Federal Parliament was

Figure 24 – Faecal Coliform counts for selected rivers and lakes (numbers per 100 milligrams)

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opened in Melbourne on May 9th 1901 (Canberra was later chosen as the nation’s capital in 1909) feedlot — in agriculture food such as grains is brought to livestock such as cattle in order to fatten them before slaughter later to be sent to market. These areas (pens) are called feedlots fen — a lowland area covered with shallow water with decaying vegetation producing neutral or alkaline soil material (see alkalinity) feral — unnatural or wild eg feral cats that have been introduced into the Australian environment Ferrell cell — part of the general circulation. The Ferrell cell is created by the dynamics of the Earth’s rotation and differences in the density of air moving from the south and from the north. At latitide 30°S where air is sinking, some air moves south; this warm, less dense air moves to latitude 50°–60°S. When this air meets the cold, dense air moving from the south, the less dense air is forced to rise. There is then a return flow in the upper troposphere north and south. The cold dense air then sinks. (see figure 26) Ferrell’s law — the law or rule that states that if you are in the Southern Hemisphere winds are deflected to the left while in the Northern Hemisphere winds are deflected to the right (due to the coriolis force). This also applies to ocean currents (see Ekman spiral) ferricrete — an iron-rich duricrust fertility rate — the average number of children a women can expect to have (eg a fertility rate of 2.5) festival marketplace — an urban area that combines retailing and entertainment, often in former railway yards, converted non-retailing buildings, and formerly blighted urban districts fetch — the distance a wind travels over the sea eg “the fetch of the wind is 200 km” field capacity — when soil material cannot take up any more water.

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Following infiltration as field capacity is reached water can be seen to flow across the surface (overland flow) fieldwork — the planned and coordinated collecting and generating of new information through active inquiry via primary research fiord — a flooded glacial valley. During very cold periods of Earth history such as the ice age, glaciers formed at high altitudes. Many glaciers grew and reached sea level. At this time sea level was much lower than present because a lot of water was trapped in ice caps such as Antarctica. Temperatures warmed, ice caps and glaciers melted and the sea flooded the valleys formed by the glaciers. These flooded glacial valleys, or fiords, are found along the coast of Norway (in Scandinavia) and the west coast of the South Island of New Zealand firestick farming — the use of fire to burn grassland in order to capture animals for food, to provide nutrients to the soil or to encourage plant regrowth; this technique was practised by traditional Aborigines in Australia (especially before white settlement) firn — a term used to describe the snow that falls in winter and remains throughout summer until the following winter without becoming glacial ice first world — a term not used widely today. In the past it referred to countries such as USA, Australia, Japan and those of Western Europe. These industrialised countries are now referred to as developed countries, The North or The Minority World (see second world and third world) fissure — a long fracture in the Earth’s surface such as on the crust or even a glacier where there is a vertical displacement or gap fissure eruption — a volcanic eruption where lava is extruded from a long fracture in the Earth’s surface — such as along an ocean ridge beneath the oceans and across Iceland rather than from a single volcano (see extrusion)


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Flandrian transgression — a term used mostly in Europe to describe the global rise in sea level after the last glacial period approximately 10,000 years BP. During the last glacial period a great volume of water was locked up in glaciers as well as the Greenland and Antarctic ice caps. A marked regression occurred with sea levels falling approximately 150 m. As temperatures warmed the ice melted and sea levels began to rise submerging the previously exposed continental shelves and drowning river valleys and glacial valleys. Tasmania and Papua New Guinea became separated from the Australian mainland at this time, as did the British Isles from Europe, and Sri Lanka from India (see ice age) flocculation — the process whereby particles adhere or clump together forming large substances that eventually settle out in a fluid. An example of flocculation is in sewage treatment. A powder called alum is added to sewage in a sewage treatment

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plant. The electrically charged particles of the alum attract the solids within the sewage forming heavier clumps that settle out, sink to the bottom of a treatment tank and can then be removed. The use of Alum is being phased out in favour of alternative flocculants floodplain — the low-lying land adjacent to a river channel inundated by water during flood periods and on which alluvium is deposited (see figure 25). The processes of floodplain sedimentation are varied. Some are built up by lateral deposition on the slip-off slope of meanders; others are formed where channels switch between braided reaches. Overbank deposits from flood periods typically provide small amounts of floodplain material; indeed some floods are highly erosive events flood pulse — description of a particular flow event in the flow record of a river flora — an alternative term for vegetation (see fauna)

Figure 25 – Fluvial Terrain

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flow-line map — a type of map that shows the direction of movement and/or the quantity of movement between places fluvial — relating to rivers eg fluvial landforms are those created by the action of rivers (see figure 25) fluvial erosion — erosion that is the result of fluvial (or river) processes. The erosion of a riverbank can be the result of high velocity water flow; the scouring and wearing down of the riverbed by rocks is the result of fluvial erosion focus — the focus of an earthquake is the point below the Earth’s surface where the earthquake occurred — directly below the epicentre; the focus may be at 10, 20, 100, 200 or more kilometres deep föhn effect — a warm, dry wind blowing down the leeward slope of a mountain area. The air is warm because of the subsiding air in the atmosphere being compressed and therefore heated up (see also chinook) fold — a deformation in the Earth’s crust where lateral (sideways) pressure has compressed bedding planes to form folds. Resulting landforms can range from small hills to high mountains fold mountains — mountains that are the result of crustal movement within the Earth forcing the land to rise in a series of folds called anticlines and synclines. Mountains such as the Himalayas are fold mountains where one lithospheric plate has collided with another forcing the land to rise forming the Himalayas. The Himalayas are built up of seafloor sediments squeezed up like toothpaste between two lithospheric plates (see continental drift) food chain — the observed relationship between living organisms where one living organism is dependent on another as a food source (eg an ant eaten by a lizard, the lizard in turn eaten by a cat). (see food web) food web — the series of interconnected food chains within an ecosystem; one

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food source within a food chain may be a food source in other foodchains footloose industry — industries that can be located without particular reference to raw materials, energy or markets. Sophisticated infrastructure allows many industries to change their location according to perceived locally advantageous circumstances foredune — the large dunes at the back of beaches and within which dense vegetation is growing. They are typically the result of a prolonged period of deposition and the process of plant succession that may have developed a climax community. Foredunes can be very large eg 20–30 metres high (see figures 4 and 14) foreign aid — assistance given to poorer countries of the world in the form of grants and low interest loans. There are different types of aid: • Bilateral Aid: it is aid provided by one government to another government • Emergency Aid: aid in the form of food, clothing and medicines following disasters such as floods and earthquakes • Multilateral Aid: where aid is given from a number of international organisations such as the United Nations via the International Monetary Fund • Tied Aid: aid is given with the country giving the aid setting conditions that must be met by the country receiving the aid. For example, aid given for bridge or dam construction might be given on the condition that the country giving the aid has access to port facilities • Untied Aid: where a country receiving aid in the form of money is free to spend this on any project it wishes foreshore — the area of beach between high and low water marks forest — a continuous area of tree cover where the dominant tree species range


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between 30 and 70 metres high and where the density of the canopy cover may be between 30% and 100%. As a result, there are many different types of forests depending on structure (height and density) and species eg tall open forests and closed forests (as in rainforests) and temperate forests where these more sparse forests are dominated by eucalypts such as in SE and SW Australia formal region — an area of the Earth’s surface marked by relatively uniform characteristics. In many cases, formal regions are distinguished by their biophysical characteristics and show clear and concise boundaries such as being marked by a catchment boundary, a river, a type of soil type or geology (see functional region) formal sector — that part of the economy that makes up the official paid workforce. People working in the primary, secondary and tertiary sectors that are paid for their work and pay official taxes belong to the formal sector. The types of jobs in this sector include doctors, secretaries and labourers (see informal sector) fossil fuel — a non-renewable natural resource such as oil, coal and natural gas. Fossil fuels have been produced over millions of years following the decomposition of living matter such as vegetation. Fossil fuels are typically found in sedimentary basins beneath the Earth’s surface. franchise — a small business set up where the business agrees to use the trademark of a larger business and distribute its product. As such, there may be many small businesses of the same name, each operating independently, but agreeing to abide by the larger company’s standards and quality of service freehold tenure — land owned privately (see leasehold land) front — the boundary between two contrasting air masses (see cold front; warm front)

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frontal dune — a large sand dune at the back of the beach that has recently been stabilised by vegetation (as distinct from the much smaller embryo dune. The frontal dune is the most seaward of the large stabilised dunes and is subject to the erosive power of waves frontal rainfall — rainfall that results from the interaction of two contrasting air masses. Frontal rainfall can result from the passage of a cold front over an area. As a parcel of cold, dense air moves towards an area with warmer, less dense air, the less dense air is forced to rise. As the air rises it cools, eventually forms clouds, and may rain. This is called frontal rainfall. Rainfall tends to continue for an extended period of time such as a week compared to the more brief episodes associated with convectional rainfall (see figure 50) frontal uplift — the forced rising of air as a result of the different air densities (see frontal rainfall) frost shattering — an example of weathering common in cold climates such as in glacial and periglacial environments and those of high altitude areas, especially above the snowline. Estimates of Fuelwood Consumption in Selected Countries Country

Wood as a % of total energy consumption

Mali

97

Nepal

98

Rwanda

96

Chad

94

Tanzania

94

Burkina Faso

94

Ethiopia

93

Somalia

90

Burundi

89

Niger

87

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Water can exist in a liquid state during the day in some of these areas. However during the night, lower temperatures can lead to any water in the cracks of rocks to freeze. The expansion of the ice splits or shatters the rock into smaller pieces fuelwood — wood that is collected or grown to be burned to provide energy for heating and cooking. Fuelwood is used extensively in developing countries fumerole — a small vent in the Earth’s surface through which hot steam and other gasses pass. They are much smaller than volcanoes and can occur on the sides of volcanoes functional diversity — the characteristic of a place where a variety of different economic, social and political activities occur; most often associated with urban places functional region — an area of the Earth’s surface showing distinctive

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interrelationships which highlight its function; for example • a city shows trade and communication flows, the movement of people and the relationships between people and the natural, economic, social and political environments) and • a catchment area shows linkages between features such as topography, vegetation, soil and various land use types) fungi — organisms such as mushrooms and mildews – neither plant nor animal. Fungi are important in the environment in that they decompose (break down) organic matter, such as on the floor of a rainforest, and return nutrients to the soil and eventually vegetation fungicide — Fungi can produce diseases. Various chemicals, called fungicides, are used to control these diseases

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new geography dictionary geography dictionary new dictionary new geography

G

G7 (Group of Seven) — a group consisting of the world’s seven most industrialised nations formed in 1975 (Germany, Canada, USA, France, Italy, Japan and the United Kingdom) G8 (Group of 8) — the countries indicated in G7 with the addition of Russia Gaia hypothesis — the idea that the Earth is one large living organism acting as a single system. As such, aspects of the atmosphere, lithosphere, hydrosphere and biosphere are so intricately interconnected that, not only is there a response by one of these spheres to changes in the other, but such global responses can be due to local disruptions. Proposed initially by James Lovelock the name is derived from ‘Gaia’ the Greek Earth Goddess. The Gaia hypothesis lies at the heart of many environmental philosophies where understandings and decisions are based on the idea that any impact on the local or global environment will see a response by the Earth (ie from Gaia, the Earth Goddess) gallery forest — the long continuous cover of dense trees along the banks of some rivers especially in an otherwise dry environment. For example a ‘ribbon’ of trees can be seen winding across the land following the path of an unseen river. These can be particularly seen with the aid of aerial photographs gated communities — or commoninterest developments (CIDs) promote exclusiveness, amenities and security. In extreme cases computers check

entry cards, laser beams sweep the perimeter, and TV cameras monitor the movement of people GATT — General Agreement on Tariffs and Trade (UN) gazetteer — a book providing an alphabetical list of places and features on the Earth’s surface as well as additional explanatory information GDP — Gross Domestic Product. This is the total value of goods and services produced by a country. Gross Domestic Product per capita is a measure of GDP divided by the total population gelifluction — a type of solifluction typically in periglacial areas. Water within the regolith accumulates above the level of permafrost as well as from melting lenses of ice within the soil. The body of the regolith above the permafrost moves downslope as a slow-moving mass (eg 1–10 cm per year) general circulation — the circulation or movement of air in the atmosphere — both vertically and horizontally; the result of the variation in the heating of the atmosphere between latitudes as well as the rotation of the Earth (see figure 26). The Sun’s rays are most intense in the low latitudes (eg tropical latitudes). The warm air rises forming areas of low atmospheric pressure. At the poles the air sinks forming an area of high pressure. However between the equatorial and polar latitudes the Earth’s rotation influences air movement. The air rises in equatorial latitudes through the troposphere. When it reaches the tropopause the air moves north and south (because it cannot normally break through this inversion The New Geography Dictionary

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layer). In the Southern Hemisphere, for example, this cold air sinks at approximately latitude 20–30°S forming an area of high pressure. Some air returns to the equator in the form of the southeast trade winds completing what is called the Hadley cell. Some of this (warm) air of the subtropical high pressure cell moves south and is deflected to the left forming the strong westerly winds at approximately latitude 40°–60°S. Cold air coming from the polar latitudes forces the warmer, less dense air ahead of it to rise. This area of low pressure with its associated cold fronts completes what is called the Ferrell cell. The cold subsiding air over the polar latitudes forms an area of high pressure. The cold air moves north to meet the rising limb of the Ferrell cell. Some of the air that is forced to rise returns to the polar latitudes to complete the Polar cell

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genetic engineering — a name given to the wide variety of techniques that take a gene from one cell and insert it into another cell. As a gene enters a cell it can change the way that cell works. A controversial technique, genetic engineering can be used to artificially create new medicines and medical procedures; it can be used to manipulate the genes in the cells of crops producing new and new varieties of crops genome — the genetic material that is characteristic of a particular species. A major international effort has succeeded in mapping (or identifying) the human genome. In doing this it is possible to identify specific genes responsible for human traits such as hair colour as well as those responsible for the occurrence of specific diseases

Figure 26 – The general circulation of the atmosphere

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gentrification — the transformation of an urban area by replacing an older established socioeconomic group or age group with that of a younger group. Often the average age of the area falls, average incomes are higher and the residential areas undergo restoration geochronology — the study of determining the age of the Earth. Geochronology uses relative dating techniques as well as absolute dating techniques. Relative dating attempts to place features in chronological order such as with the use of tree rings and varves; whereas absolute dating attempts to give a precise date expressed in years such as with radiocarbon dating and potassiumargon dating (see figure 12) geographic issue — an area of concern that people may have about aspects of the biophysical environment or social environment which can be investigated from a spatial dimension or ecological dimension (see contemporary geographic issue) geographical mile — a measure of length equivalent to 1" (one minute) of latitude (ie 1/60th of a degree). Although this distance varies between the equator and the poles, it is generally considered to be approximately 6,080 feet (or 1853 metres) geographic information system (GIS) — a computer system which can receive, analyse, manipulate and display geographic information geography — at its simplest form geography is concerned with place; that is where things are. The discipline of geography has changed over time reflecting social, economic and political concerns of the day. The qualitative or descriptive approach to geography in the morphological tradition of the 1940s and 1950s was characterised by the detailed description of landscapes and landforms; the process tradition of the 1960s and 1970s identified and described the processes in and

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features such as rivers, coasts, deserts urban areas etc. The more quantitative approach since the 1980s saw the increased use of statistical analysis and the use of computer technology. In all, geography is attempting to identify and describe patterns on the Earth’s surface and explain their spatial patterns and temporal changes. In doing this geography’s chief concern is that of the total environment – the natural world, such as rainforests, the modified world, such as agricultural areas, and that world created by people, such as urban communities. Although there are various branches of geography such as physical geography, human geography and political geography, in all cases geography is about identifying and explaining patterns and offering sustainable solutions to provide for an increasing quality of life of people. The last decade of the twentieth century focussed on the concept of a sustainable world. The world may well be closing in with the explosion of information and communication technology. However geography of the twenty-first century will increasingly address the power and position of the nation state and the quality of lives of people in an increasingly polarised world – despite the pleas of the ‘globalists’ and ‘economic rationalists’ geoid — a term used to describe the shape of the Earth used nowadays to describe an Earth-shaped body. The Earth’s is pear-shaped because of the slightly greater diameter of the Earth just south of the equator. This is called an oblate spheroid. geological time scale — a scale recording the history of the Earth at well-defined time intervals (Figure 27). Geologic time extends from the period of time before the Precambrian Period 4.5 billion years ago to approximately

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C

I

0

Z

0

408 439 510 570

DEVONIAN SILURIAN ORDOVICIAN CAMBRIAN

ARCHEAN

4500

2500

245 290 362

208

146

TRIASSIC PERMIAN CARBONIFEROUS

JURASSIC

PRECAMBRIAN PROTEROCOIC

PALEOZOIC

MESOZOIC

CRETACEOUS

Paleocene

R

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65

35.4 56.5

Oligocene Eocene

E

5.2 23.3

TERTIARY

Pliocene Miocene

CENOZOIC

1.8

Sea levels and temperatures rise as ice caps melt after the earlier glacial cold – reaching present levels by approximately 6000 years ago Temperatures plummet. Sea levels fall up to 200 metres below present levels and New Guinea and Tasmania are linked by land. Homo Sapiens walk the land. Occupation by Aboriginal groups at Lake Mungo (NSW) and Kow Swamp (Victoria) indicate brief wet periods followed by more aridity. Temperatures are at their coldest 17,000 years ago The Australian plate has been colliding with the islands and Pacific Plate to the north forcing up the New Guinea Highlands. As sea levels fall during this glaciation the first placental mammals enter from the north Evidence of the first marsupials in Australia. The Eucalypts followed by the Acacias and Banksias dominate the land – as do the giant Megafauna such as Diprotodon, Procoptodon and Thingodonta Australia is drifting north to the drier sub-tropics. Aridity is Australia’s fate. The break between Australia and Antarctica is almost complete. The seas flood the Nullabor Plain and the Murray-Darling Basin. The warm-blooded mammals now abound The Tasman Sea between Australia and South America begins to open 80 million years ago. A global extinction of land and marine organisms occurs – the most famous being the dinosaurs The southern conifers (such as the Huon Pine) disperse across Gondwana. Gondwana begins to tear apart and the sea invades the continent As Pangea begins to split up; major rifting along the west coast forms the Darling Scarp. What is now Tibet drifts northwest Dinosaurs are present for the first time Animal and plant life dominate the land and the coal bearing forests take hold A continental ice sheet covers much of what will be Australia (up to 4km thick). Much of Australia's life is extinguished – the ferns are the most notable survivors Amphibians become the lords of the Earth Life emerges from the waters – millipede-like vegetarians and scavengers Tectonic forces create the Olgas and Ayers Rock Australia forms part of the land mass that will become Gondwana. An earlier continent-wide glaciation gives way to a burst of life – multicelled organisms eg the Trilobites The Hamersley Ranges emerge. Iron oxidises in the ocean and the seas begin to rust later forming the vast Red Beds eg northwest Western Australia The Pilbara forms one of the earliest land masses on Earth at 3.5 billion years old. Stromatolites become the earliest life forms on Earth

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A

QUATERNARY Pleistocene

(10,000 years)

AGE SOME KEY EVENTS IN AUSTRALIA millions of years Before Present

(and some major events in Australia's Earth history) EPOCH

H

PERIOD Holocene

ERA

P

EON

Figure 27 – Geological Time Scale

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570 million years ago. The Cambrian Period followed marked by an explosion of life forms. The Cambrian Period to the present day is marked by Periods indicating the emergence of distinctive life forms eg The Silurian Period (the age of fishes, 430–395 million years ago). The most recent Period is the Quaternary Period (2.8 million years ago to the present). The Quaternary Period is marked by the Pleistocene Epoch and the Holocene Epoch that began at about 10,000 years ago – and includes the present day geomorphology — a field of study which attempts to describe and understand the natural features of and the processes operating on, the Earth’s surface. For example, a coastal geomorphologist describes coastal environments and landforms such as beaches, waves, sand dunes and rock platforms and attempts to provide explanations for these features

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geophagy — eating dirt or clay geophyte — a plant that has parts beneath the ground surface that can survive after that part above the ground has died off geopolitics — the name given to that branch of geography, political geography, concerned with the changing social, economic and political face of regions and/or countries around the world. Geopolitics addresses the power relationships between nations as well as the strategic decisions of nations to sustain or increase their power base on a regional or global scale geosyncline — a depression in the Earth’s surface extending for 100s or 1000s of square kilometres into which vast quantities of sediment accumulate over millions of years. Sedimentary rocks develop to depths of several kilometres below the surface. Geosynclines are ideal sites for the accumulation of hydrocarbons which include economically viable reserves

Figure 28 – A Glacial Terrain

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of reserves of oil, coal or natural gas such as within the Sydney Basin, NSW Australia and beneath parts of the Middle East geothermal energy — heat energy obtained from within the Earth. For example steam is obtained from vents in the Earth’s surface which is used by geothermal power stations to generate electricity. Geothermal energy is considered a renewable natural resource. It is used extensively in New Zealand and Iceland gerrymander — the deliberate redrawing of political boundaries to maximise an electoral advantage of one party over another. This is a form of electoral bias geyser — (or hot spring) a hot water fountain that erupts intermittently with great force. ‘Old Faithful’ in the USA is the best-known geyser; it erupts every three minutes sending a jet of hot water as high as 60 metres into the air ghats — the mountains to the east and west of the Deccan plateau in central India. The mountains are known respectively as the Eastern and Western Ghats ghetto — a small area dominated by a minority group gibbers — these are small stones on the surface of some Australian deserts. Deserts where these gibbers are widespread are called gibber deserts – as opposed to sandy deserts (see reg; see figure 20) giffen goods — giffen goods are often referred to as inferior goods where commodities of a relatively low price form a significant component of the diet and livelihood of low income earners gigalitre — one thousand million litres (also written as GL) gilgai — originally an Aboriginal word, ‘gilgaay’ meaning waterhole. It is now used to refer to terrain of low relief made up of small mounds resulting from the alternating periods of expansion and contraction following wet and dry weather.

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Gilgai are found typically in semi-arid areas where summer temperatures are high and rainfall variable. Gilgai relief can range from a few centimetres to several metres and up to 10 metres apart glacial — a landscape occupied or formed by glaciers and glacial conditions (see figure 28) glacial period — a period in Earth history that saw temperatures much lower than present, as well as the development and growth of glaciers during an ice age glacial valley — a valley formed by the power of a glacier (see figure 29 colour, U-shaped valley) glaciation — a process that sees the expansion of glaciers and glacial conditions typified by cold conditions. The last glaciation (or glacial period) on Earth was during the Pleistocene epoch. Within this last global glaciation there have been many glacial and interglacial periods. The last glacial period was at its coldest at approximately 17,000 years B.P. When glaciation was widespread especially in the Northern Hemisphere large icesheets covered much of Europe and northern North America. Australia was limited to a small 50 km2 icecap on Mount Kosciuszko glacier — the result of the accumulation of snow and ice. Under its own weight, this ‘river of ice’ can move downslope along a well-defined channel (see glacial valley) glei soil — soil that has developed under wet or even saturated conditions where the water table is close to the surface. The soil or even a horizon in that soil my take on a greyish-blue colour global commons — see common(s) global economy — the increasingly interconnected global system of production and trade. Associated with the global economy are the increasing linkages between individual countries as well as the rise of global manufacturing, marketing and finan-


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cing. The global economy has seen the decline in the nation state being able to operate in isolation globalisation — a process of increasing integration of economic, social and political activity around the world. As a result of a faster and more efficient transport network and advancing computer technology, the individual nation state is becoming less of a force on the global scene. An example of the globalisation process can be seen with the emergence, since the 1970s, of global businesses in the form of transnational corporations and the power they exert on domestic and foreign governments global-local nexus — the connection between global and local forces whereby global forces are seen to be more powerful and spatially important whereas local forces are relatively weak and less geographically effective global positioning system — a satellite navigation system which is used to determine positions in three dimensions (GPS) global warming — a warming of atmospheric temperatures during the twentieth century. The cause of global warming has often been attributed to the build up of carbon dioxide in the atmosphere from the burning of fossil fuels used for heating and as an energy source for transport and industry. There is the alternative view that global warming is a natural process of the atmosphere as temperatures rise and fall within a glacial cycle glossopteris — a fossil plant dating back to the late Paleozoic Era. It has been found widespread in South America, Africa, Australia, India and Antarctica providing further evidence supporting continental drift gobar — a fog found on the upper Nile River Golden Triangle — that part of northern Thailand, Burma and Laos known for the production of opium poppies and the illicit trade in opium Gondwana — also Gondwanaland; the name given to one of two landmasses

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that made up the surface of the Earth approximately 150 million years ago. As a result of plate tectonics Gondwana split into the present-day Southern Hemisphere continents of Australia, Antarctica, South America, Africa and Antarctica — as well as the land today known as India (see Laurasia and Pangaea) Goyder’s line — in 1870 the South Australian Surveyor General G.M. Goyder suggested that the government of the day prohibit settlement in areas unsuited to agriculture. He stated that ‘nature’ had clearly established a line beyond which permanent settlement must be given to the pastoral tenants rather than the agriculturalists. This line of demarcation between reliable rainfall in the south and where “drought prevails in the north” became known as Goyder’s Line. It extends in an arc in South Australia from Moonta on the York Peninsula in the west, to Orroroo in the north, then to near Morgan in the southeast (see pastoralism) GPS — see Global Positioning System gradational texture — in describing soil texture, a soil with a gradational texture profile is one where the texture grade gradually becomes finer (more clayey) with depth (see duplex soil, uniform texture) graded bedding — a characteristic of some sedimentary deposits where particles of different sizes have been sorted from coarse to fine particles. Typically the heavier coarse particles are at the base of the deposit and the finer particles are towards the top. graded profile — as a river erodes, transports and deposits its load along its length there may come a time where, at particular points along its course, erosion and deposition are in balance – it is neither eroding or depositing material. At this point, the river is said to be ‘in grade.’ A river will erode down as well as deposit material until this point is

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reached along its course. The point at which a river is ‘in grade’ is typically at higher elevations inland. A cross section of these points from its headwaters to its mouth is known as its graded profile (see long profile, thalweg) graded river — as a river flows downstream it erodes, transports and deposits material until base level is reached. There will come time when the river has only enough energy to transport material with no erosion. The river is said to be in grade or to be a graded river gradient — the slope of the land. A gradient of 1 in 10 means you have to walk 10 metres horizontally to go up (or down) 1 metre. Gradient can be obtained from a topographic map by looking at the contour lines. The closer together the contour lines

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the steeper the slope. The gradient can be calculated using the formula: Vertical rise (m) between the two points Horizontal distance (m) between the two points

granite — a coarse-grained igneous rock. The large crystals in granite are the result of the slow cooling of magma beneath the Earth’s surface grassland — extensive areas of tall grasses. They are almost treeless. Grasslands are a major world biome and include the savannas of northern Australia, the steppe of the Ukraine, the veldt of southern Africa and the pampas of Argentina Great Artesian Basin — a vast area beneath southwest Queensland and northwest New South Wales where sedimentary rocks have stored enormous volumes of water over millions of years.

Figure 30 – The Greenhouse Effect

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Some of this water is extracted via artesian and sub-artesian wells for irrigation of crops like cotton and for drinking by sheep and cattle great circle route — a line drawn on the surface of globe to show the shortest distance between two points. On a curved surface such as the Earth the shortest distance is not a straight line but rather a great circle great soil group — a soil that has worldwide distribution under similar climatic and geomorphic conditions. Soils have traditionally been classified under the headings of: i) zonal – those formed under conditions of good drainage and result from the long-term action of climate and vegetation ii) intrazonal – those developed under conditions of very poor drainage (such as bogs) or on limestones iii) azonal – those that have no well developed profile characteristics due either to having insufficient time to develop or the slopes are too steep to allow profile development Zonal soils of the great soil group reflect the dominance of climate and vegetation. Examples of such soils are: i) podsols – formed in cool humid

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climates. The podzol is said to form on sandy parent material ii) chernozems – formed in grassland areas in the relatively drier (semi arid) climates of the mid-latitudes. Chernozems have developed deep dark, humus-rich profiles reflecting prolonged weathering iii) latersols (lateritic soils) – formed in the warm, wet climates of the low latitudes where high temperatures and rainfall produce deep weathering and subsequent deep soil profiles rich in iron and aluminium oxides The use of great soil groups has caused great confusion among soil scientists. This has resulted from the recognition from field surveys that local soil forming factors such as slope, aspect and lithology may be just as, or even more, important in understanding soil development (see texture contrast soil, zonal model of soil formation) green politics — political decisions based on the understanding and recognition of potential environmental impact. There is a focus on ‘green issues’ such as the logging and deforestation, water and atmospheric pollution as well as issues of urban planning and increased public transport.

Global Ranking and Percentage of Global Emissions of Greenhouse Gases Rank

Country

%

Rank

1

United States

20

11

Iraq

2

2

Russia

14

12

France

1.8

3

China

1

13

Canada

1.75

4

Japan

5.5

14

Mexico

1.6

5

Brazil

5

15

Poland

1.5

6

Germany

4

16

Australia

1.4

7

India

3.8

17

South Africa

1.2

8

United Kingdom

3

18

Spain

1.15

9

Indonesia

2.5

19

Venezuela

1

Italy

2.3

20

South Korea

0.99

10

Country

%

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In Australia ‘The Greens’ are a political party with a focus on green issues greenbelt — an area around a town or city that has been left as open space or parkland with the intention that this is not to be built on greenhouse effect — the effect of the atmosphere on incoming and outgoing radiation (Figure 30). The atmosphere is made up of a range of gases such as oxygen, nitrogen, water vapour and carbon dioxide. The great bulk of radiation (short wave radiation) received from the Sun passes through the atmosphere. The radiation that reaches the Earth’s surface heats the land. The land reradiates this heat back into the atmosphere but as long wave radiation. A large proportion of this radiation is trapped in the atmosphere by various greenhouse gases such as water vapour, carbon dioxide and methane. This is the Natural Greenhouse Effect. Where the activities of people such as the burning of fossil fuels and the clearing of forests increase these greenhouse gases this is known as the enhanced greenhouse effect and contributes to global warming — the warming that results from the addition of various gases by human activity to the atmosphere greenhouse gas — a gas in the atmosphere contributing to global warming. Carbon dioxide and methane are greenhouse gases. Water vapour is the major greenhouse gas allowing for an average surface global temperature of 15°C. Carbon Dioxide is the greenhouse gas being added to the atmosphere as a result of the burning of fossil fuels and vegetation. Methane is the fastest growing greenhouse gas in the atmosphere as a result of activities such as the spread of agriculture, and the melting of the Arctic ice sheet and permafrost (see Greenhouse Effect)

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green revolution — a revolution in agriculture in the 1960s and 1970s especially in such Asian countries as Thailand and India. It saw increases in food production, in particular the yield of crops such as rice and wheat. This came about as a result of the introduction of new high-yielding varieties of seed stock as well as the application of new production techniques and capital, such as fertilisers (see HYV) green technology — technology that promotes the sustainable use of natural resources such as water, forests and energy and at the same time having little or no adverse effect on the quality of that resource or the environment generally (see natural resource) Greenwich Meridian — see Prime Meridian Grevillea — a type of vegetation in the form of a shrub or small tree commonly referred to as spider flower grey water — wastewater that can be used, not for drinking, but recycled for a range of purposes such as irrigation systems on sporting fields and cooling in industry grid — a system of vertical and horizontal lines in many cases used to determine the location of a feature eg lines of latitude and longitude grid pattern — often refers to a particular street pattern. Streets are aligned at right angle to each other especially in areas of relatively flat land as opposed to winding roads typical of more hilly or undulating land grid reference — a six figure map reference used on a topographic map eg 342658 (see figure 40) gross domestic product — see GDP groundwater — strictly all subsurface water whether liquid, solid or a gas. Groundwater usually means that water received from precipitation and stored beneath the surface below the saturated zone of the water table. Groundwater however extends deeper than this. Under the influence of


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gravity, groundwater moves slowly to feed rivers eventually to drain to the oceans — this is called groundwater runoff Group of 7 — see G7 Group of 8 — see G8 growth corridor — new areas of housing, shops, manufacturing and community facilities that follow roads and natural features such as coastlines and rivers. Growth corridors are typically driven and encouraged by State government policies in Australia (see ribbon development) guano — deposits of bird droppings especially on islands close to the coast. Such deposits can be used as fertiliser because of the high phosphorus content guest worker — there are times when there are more opportunities for work than there are workers available. In order to solve this labour shortage

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governments allow international or interstate workers to fill job vacancies for a particular period of time only — often under contract eg 3 years. These workers are called guest workers gully erosion — a type of accelerated soil erosion where deep scars (gullies) appear on the land leading to the loss of the total area of land available for cultivation and housing guyot — a seamount with a flat top. The origin of these underwater mountains in the ocean is unclear. Their flat top may be the result of erosion during times of much lower sea level but this is not proven gyre — the large-scale circulation of water in the world’s oceans. Gyres involve major ocean currents such as the gyres off the east Australian coast; and the gyre associated with the North Atlantic Ocean

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new geography dictionary geography dictionary new dictionary new geography

H

ha ha — a trench, rather than a fence, acting as a boundary around an area such as a zoo to allow the uninterrupted views of onlookers habitat — the area or environment in which a plant or animal lives hachure — shading used on a map to give the impression of the shape of the land such as the steepness of topography Hadley cell — part of the general circulation of the atmosphere. As air is heated at the equator air rises through the troposphere forming an area of low pressure. At a particular altitude (ie at the tropopause approximately 8–10 km) the air moves to the poles. In the Southern Hemisphere the air at approximately 10 km altitude moves south. As it is affected by the coriolis force the air tends to accumulate, then sink at latitude 20°–30°S forming an area of high pressure. These are the latitudes of many of the world’s deserts – eg the Great Sandy Desert in Australia. The return flow in the lower atmosphere back to the equator completes the Hadley cell (see figure 26; latitude) hail — solid precipitation which falls in the form of ice particles especially from cumulonimbus clouds half-life — the time taken for half of a substance to decay. The term is commonly used to describe the halflife of radioactive elements such as uranium. For example an element with a half life of 1000 years decays by half after 1000 years; after another 1000 years half of what remains decays; after another 1000 years half of this decays

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halo — a phenomenon in the atmosphere where a circle or halo appears around the Sun. The halo is the result of light from the sun being refracted by ice crystals in very high clouds such as cirrus clouds halophyte — a plant adapted to soils containing sodium chloride (salt) halosere — a plant succession that has evolved in relatively salty (or saline) conditions hamada — in a desert the surface is mainly bedrock (rather than the more recognisable sandy deserts) hamburger connection — the destruction of rainforest in order to produce cheap hamburger beef for the North American market hamlet — a very small settlement consisting of a few buildings in a rural area. The term is not very useful because it refers to any settlement too small to be called a village Han — the main ethnic group in China making up about 90% of the population hanging valley — during glacial periods, glaciers grow and erode deep valleys. Smaller glaciers may join them from the sides but, being small do not erode as deeply as the large glacier they join. Since the glaciers have melted and retreated up their valleys the small tributary glacial valleys ‘hang’ over the larger valley they were feeding into. These hanging valleys are often the sites of waterfalls in former glaciated environments (see figure 28) hardpan — a hard or brittle layer (or horizon) within a soil profile. A hardpan develops as a result of the processes of eluviation and illuviation. Water/minerals/soil particles accumulate within the profile and harden to form a relatively dense or


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hard area. Hardpans are often found in soil profiles developed on sand dunes in soils called podsols (see also indurated (or induration) harmattan — the name given by local people to refer to the dry dusty winds in West Africa headwaters — where the river starts. The headwaters of most rivers are found in upland or mountain areas and eventually flow to the river mouth at the sea heath — a vegetation community consisting of low dense shrubs (eg 1–2 metres high) typically growing on the infertile, sandy, acid soils of exposed plateau surfaces such as around Sydney, NSW and Perth, WA Australia. heat equator — a line joining the hottest places around the world. Isotherms join places of equal temperatures. The heat equator joins hottest places – these are not necessarily the same temperature. Although this would be expected to be along the equator, because of the uneven distribution of land and oceans this line wanders north and south of the equator – hotter areas are over the land and cooler areas are over the oceans heat island — the building materials of major settlements are made up of bricks, concrete, asphalt. These materials tend to absorb heat quickly during the day and retain it at night. However the surrounding countryside releases heat more quickly especially at night so tends to be cooler than the urban area. The warmer urban area might be 1–3°C warmer than the surrounding area – it stands out as an island of heat or a heat island. This is typical of most urban areas. The microclimate of this urban heat island is very different from the surrounding hinterland. For example besides being warmer they tend to be: • less windy; although some areas are very windy because of the wind tunnels created by some adjacent buildings,

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• cloudier as a result of the convection over the urban area and therefore wetter and more polluted from the exhausts of motor vehicles and effluent from industry heavy industry — manufacturing that involves both the processing of large volumes of heavy raw materials (such as iron ore, coal or steel products) as well as the production of high volume, high weight finished goods (such as an iron and steel works or car manufacturing). Heavy industry has become increasingly automated with the use of computer technology replacing labour traditionally provided by people (see automation, light industry, manufacturing,) heavy metal — a metallic element such as lead, cadmium, aluminium and mercury; these are generally toxic even in low concentration. In mammals they can accumulate in tissue matter ultimately causing death (as such they are bioaccumulative) hectare — an area of 10,000 square metres in size (100 m x 100 m) hectolitre — one hundred litres hectopascal (hPa) — the unit used as a measure of air pressure at a point over the surface of the Earth. Millibars were previously used helicoidal flow — an unstable flow regime in a fluid such as a river where cross currents interact with the main channel flow setting up a spiral motion or eddy within the flow. The spiral motion is elongated in the direction of stream flow. In a river the spiral motion sets up a meandering flow with the outside of the meander bend eroded while the inside of the meander bends include point bar deposits indicating deposition. A similar process occurs in winds in the formation of desert longitudinal sand dunes helictite — a speleothem that appears to defy the law of gravity, growing in any direction such as horizontally out of a cave wall. Growth may change

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direction as crystal growth changes abruptly but most growth follows a curved path (see stalactite and stalagmite) hemisphere — in Geography areas north of the equator are in the Northern Hemisphere; those south of the equator are in the Southern Hemisphere herbivore — a plant-eating animal such as a Koala (see carnivore and omnivore) heritage value — the aesthetic, historic, social or scientific significance of places, objects (eg a house) or even languages to the community today or to future generations Herodotus — a Greek geographer /historian around 450 BC who was one of the first people to recognise relationships and vastness of time involved in Earth surface processes. On travelling through the lower Nile River valley he recognised the effects of individual floods in laying sediment on the Nile delta. He then concluded that the delta must be ‘very old’ if one flood lays down a single layer of sediment heterotroph — a term used to refer to organisms that do not produce their own food but consume other organisms such as vegetation to gain nutrients and energy. Examples include lions, kangaroos and deer. Heterotrophs include the herbivore, carnivore and omnivore – the consumers hibernation — a dormant state of an animal in winter where its body temperature is very much reduced so that its metabolism is very much reduced (see estivation) high income economy — those countries with a GDP per capita greater than $9500. Australia, USA and France are examples high order goods — in the study of population and settlement or even economic geography a high order good is one which is relatively expensive and one in which people

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will travel a relatively long distance to obtain. For example people will travel a long distance to purchase a car or even furniture compared to a newspaper (see low order goods) high pressure cell — an area of high pressure consisting of closed isobars. In a high pressure cell the value of the isobars increase towards the centre (ie the pressure increases). In the Southern Hemisphere winds blow in an anticlockwise direction around a high pressure cell (see air press, low pressure cell, figure 55) hinterland — commonly used to refer to the area around a city or other urban area. The hinterland is linked to the urban area it surrounds such as by transport, trade and communication links. For example the hinterland may provide food via market gardens whereas the urban area provides employment and goods and services – both areas linked by road, rail and computer technology hoar frost — a deposit of ice having a crystalline appearance and forming at temperatures below 0ºC holding — land legally held by a landowner or tenant eg a one hectare holding Holocene — a subdivision of the Quaternary Period following the Pleistocene. The Pleistocene was marked by many fluctuations in temperature typified by glacial periods. By 10,000 years ago temperatures warmed close to those of today. This signaled the start of the Holocene. Some people believe that we are still in the Pleistocene Period and that the present climate should be described as an interglacial within the Pleistocene ice age (see figure 27) homo sapiens — the modern human race honeycomb weathering — the breakdown of rock material by the action of salt crystallisation producing a honeycomb pattern in the rockface (figure 31 colour)


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horizon — (see soil horizon) horizontal integration — a type of business expansion where a business expands into a similar line of business in the production process; for example a food processing business expanding by taking over another food processing business; a retail chain may expand by taking over another retail chain (see vertical integration) horn — a landform typical of glacial environments where 3 or 4 cirques have met after a long period of weathering at the top of a mountain. Where the ridges associated with these cirques meet a sharp peak or horn is formed. The Matterhorn in Switzerland is an example (see figure 28) horticulture — the growing of flowers, fruit and vegetables. Horticulture is an intensive form of agriculture, typically on small areas of land and using high inputs of capital such as machinery and fertilisers. The growing of tomatoes in greenhouses especially in winter is an example of horticulture (see intensive farming,/agriculture/land use) Horton overland flow — is defined as overland flow that occurs when rainfall intensity is so great that not all the water can infiltrate. This type of overland flow is common in semi-arid environments but relatively rare in humid-temperate regions where the role of vegetation has a critical role in this distinction (see infiltration, runoff) hospitality industry — that part of the economy concerned with providing services, such as entertainment, for guests hot spot — an area where magma has accumulated within the Earth’s crust or upper mantle. The magma may find its way to the surface to form a volcano as a plate moves across it. An example of this is Hawaii today. Over the past 40 million years as Australia has drifted north it has passed over a hot spot, now located in the Southern Ocean, with volcanoes formed initially in what is now

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northeast Queensland extending south into what is now Victoria (see continental drift, volcano) Hoyt, H. — in 1939 Homer Hoyt proposed a model of urban structure. His sector model suggested that areas of highest rent tended to be alongside the main lines of communication and that that cities grow in a series of wedges. He built on the earlier concentric zone model of E.W. Burgess (see Burgess, E.W., figure 58) human development index — a statistical measure that gives an indication of the quality of life of people in an area such as a country based on factors including education, life expectancy, food intake and political freedom. The index ranges from 0–100 with greater than 80 indicating a high level of development (eg Australia, France and Canada) and less than 50 indicating a low level of development (eg Laos, Togo and Nicaragua) human geography — a branch of Geography concerned with the processes and patterns created by people on the Earth’s surface; for example population growth and movement, employment, city or urban dynamics as well as land use and land use change. Human geography during the last quarter of the 20th century became immersed in lengthy debates concerning the underlying philosophies of Geography. Some geographers were attracted to Marxism and others to philosophical currents that have examined the nature of power, knowledge and representation. A focus has been placed on the eclipse of modernism by a post-modern age and artistic representation together with its expression in complex forms of post-structural discourse. Geography has come to the fore in both contemporary social science and cultural studies (see post-modernism, post-structuralism) humanism — the philosophy or view that emphasises the human values,

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humanity or even the quality of human lives in an area of study Humboldt current — an ocean current carrying cold water northwards along the coasts of Chile and Peru in South America. This is an important current economically to the fishing industries of these countries in that it brings cold Antarctic waters and deep sea fish to the surface humic acid — a weak acid produced as a result of the breakdown or decomposition of organic matter (see humus). Humic acid moves in solution typically within soil material. Humic acid is an important agent in the chemical weathering of a wide range of minerals in rocks – eg limestone and sandstone (see humus) humidity — see relative humidity humus — partially or completely decomposed organic material such as vegetation, in the soil. Humus (or humic material) provides nutrients to the soil later to be taken up by vegetation and can often be seen in

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the upper horizon of soils (see soil horizon) Huon Pine — a descendent of the conifers that dominated the Gondwana forest approximately 100 mya. The Huon Pine thrives in Southwest Tasmania – the oldest known living tree in Australia (2000–3000 years old). Its distribution and numbers have been severely diminished as a result of logging in the 19th and 20th centuries hurricane — an area of intense low air pressure common in the Caribbean Sea and Gulf of Mexico, south of the United States bringing strong winds and torrential rainfall. These types of intense low pressure systems are called tropical cyclones in the Australian/Indonesian region and typhoons in Asia (see low pressure cell) Hutton, James — a Scottish physicist (1726–1797). After extensive field experience he came to the conclusion that no more than present day processes were needed to explain the

Figure 32 – The Hydrologic Cycle

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past. The phrase ‘the present is the key to the past’ was coined and summed up by the term ‘uniformitarianism.’ However because of our knowledge of past environments and their associated processes (for example previous glacial processes in present humid or even arid environments) a better phrase might be that ‘the past is the key to the present.’ Similarly Hutton’s ideas have been modified with the increasing acceptance of catastrophe theory (or catastrophism) – for example the impact of earthquakes, tropical cyclones on landscape evolution hybrid — an organism that is produced by parents of a different species. The process of hybridisation often leads to sterile offspring hydration — the process whereby a mineral (not containing a water molecule) takes up water from a different mineral leading to the

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breakdown or disintegration of the rock hydraulic action — the pressure exerted by the compression of a fluid. The action of waves crashing into cracks in a sea cliff wall exerts pressure and eventually leads the breakdown of the rock and collapse of part of the sea cliff. Similarly the action of running water in a river exerts hydraulic pressure on the bed and sides of the river eventually deepening and widening the river hydrocarbon — chemical compounds containing hydrogen and carbon. The term hydrocarbon is commonly used for the variety of fossil fuels such as oil, coal, natural gas and oil shale hydroelectric power — energy, such as electricity, generated from the power of running water. The Snowy Mountains Hydro-Electric Scheme in Australia generates hydroelectric

Volumes and Transfers of Water on a Global Scale

VOLUME of water /km3

TRANSFERS of water /km3

Atmosphere Inland water

13,000 freshwater lakes

100,000

saline lakes and inland seas

105,000

rivers soil moisture groundwater

8,200,000 27,500,000

Subtotal (land)

Oceans

1700* 70,000

ice caps and glaciers biota

Land

Runoff **

evaporation

70,000

precipitation

110,000

evaporation

430,000

precipitation

390,000

surface groundwater

Winds **

39,000 1000 40,000

1100 35,900,000

Oceans

1,350,000,000

Total – all water

1,385,900,000

* estimated at any one moment ** these are the same quantities transferring water between the ocean and the land and back again Swamp water and water held in permafrost are incorporated in above figures. Data collated from a range of sources: World Resources Institute; PH. Gleick ed, Water in crisis: a guide to the world’s freshwater resources, Oxford University Press, 1993

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power as water from rivers such as the Murray River is diverted and used to flow over turbines to generate electricity. This electricity is transported by cables to provide energy for many communities hydrograph — a diagram showing the changing stream discharge usually related to changes in rainfall amounts. A hydrograph record changes in water flow as a result of increased rainfall in the headwaters of a catchment area hydrolysis — a form of chemical weathering; the breakdown of organic compounds through their interaction with water hydrologic cycle — the cycling or transfer of water between various storages such as oceans, lakes and the atmosphere. This occurs through a variety of processes including evaporation, condensation, precipitation and runoff within the biophysical environment (see figure 32). Solar energy drives the hydrologic cycle. Water is evaporated from the oceans as well as the land. As air rises it cools and condenses, may reach dew point and then precipitate. Precipitation, reaching the surface can be lost in the form of evaporation or from vegetation in the form of evapotranspiration. However some may find its way to the surface of the land, to flow across the surface as runoff. Some water will infiltrate into soils to form groundwater. Groundwater runoff will eventually flow to a river. Surface runoff in the form of rivers may eventually flow to the sea. The hydologic cycle continues. The processes and quantities involved vary greatly around the world such as in desert and rainforest areas. Estimates of global volumes of water stored and transferred vary. However approximate values can be seen in the table above (see condensation, infiltration) hydrophyte — a plant adapted to permanently wet conditions. These plants have some parts submerged

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under the water that survive even when parts above water die back hydroponics — the cultivation of crops in the absence of soil. Crops are fed via chemicals and organic elements in a solution of water hydrosere — a plant succession in a wet environment. A mangrove community has developed and evolved in wet conditions especially along coastlines and at the river mouths. Hydroseres can also be seen to have culminated as inland swamps where water remains on the surface due to local biophysical conditions. Such conditions include clay soils not allowing water to drain away and even in areas of internal drainage where water flows inland to a common low point (eg Macquarie Marshes, NSW, Australia) hydrosphere — the sphere of the Earth dominated by water. This includes the oceans, rivers, lakes and groundwater in liquid, solid and gaseous form. Within the hydrosphere water is stored in locations such as the oceans (liquid) and the atmosphere (gas) and the ice caps (solid). Water is transferred from one place on the Earth to another place in its different forms. This is the hydrologic cycle. • About 70% of the Earth’s surface is covered by water • 97.3% of all water is found in the oceans • Each year approximately 500,000 km3 of water is evaporated from the Earth’s surface • 430,000 km3 from the oceans and 70,000 km3 from the land • Each year approximately 500,000 km3 precipitates on to the Earth’s surface, 390,000 km3 over the oceans and 110,000 km3 on to the land • 40,000 km3 of the water precipitates over the land and returns to the sea as runoff • 40,000 km3 is returned to the land as water vapour via winds


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hygrometer — an instrument for measuring relative humidity of the atmosphere (see psychrometer) hypermarket — a superstore of at least 50,000 ft2 (4600m2) of sales area hyper-reality — a condition where the fake feels more real than the original, for example Main Street USA in Disneyland or the theme park techniques used in shopping malls

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hypsometric curve — or hypsometric graph, a curve on a graph to show the proportion of land above and below a datum such as sea level hythergraph — a type of graph, which has monthly temperatures, plotted against monthly precipitation HYV — high yielding variety, eg rice, producing much higher yields than normal varieties (see green revolution)

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new geography dictionary geography dictionary new dictionary new geography

I

ice age — a period in the earth’s history when temperatures were much lower than present and vast ice sheets covered much of the Northern Hemisphere continents in the mid and high latitudes. The most recent ice age occurred during the Quaternary Period. Most of this Period is known as the Pleistocene Epoch (commonly called the Pleistocene). During the Pleistocene temperatures varied by as much as 10ºC. The cold phases are called glacial periods when ice cover expanded. These were separated by warmer interglacial periods. The coldest period of the last glacial was about 17,000 years ago when sea levels were up to 200 metres lower than present. The last glacial period ended about 10,000 years ago after which glaciers retreated to higher altitudes, sea levels rose, and temperatures began to approach what they are like today (see figure 27) igneous rock — a rock formed deep beneath the earth’s surface from the slow cooling of magma. Granite is an example of an igneous rock Iguaçu Falls — a spectacular series of waterfalls (cataracts) over 3 km long. The waterfalls form part of a world heritage site on the Argentina-Brazil border (see world heritage list/site) illuviation — the deposition of soil particles within a soil profile – sometimes forming a distinctive layer (or soil horizon) recognised by a colour change or change in hardness (see eluviation, hardpan) ILO — International Labour Organisation 88

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IMF — International Monetary Fund. A fund to which developed countries contribute. The money is then given to specific projects that the World Bank believes would benefit developing countries immigration — the movement of people into an area. International migration involves people moving from one country to another. The movement of people into Australia from Canada is an example of immigration (see emigration) immigrant — a person who moves or has moved into another country. For example an immigrant is a person who has moved into Australia from France imperialism — a term used to describe the invasion and subsequent control of one country by another country. In many instances the term has negative connotations following the early colonisation and control (in many cases oppression) of developing countries of Africa, Asia and South America during the 1700s and 1800s. The country taken over has a great deal of dependence on the colonising country. These colonial powers (or imperialists) have sort to expand territory or exploit available natural resources. However the political system of this imperialist state is very unstable as a result of conflict between power blocs as well as the indigenous community. This instability was seen especially during the 20th century as indigenous power saw independence movements flourish – in many instances through violent revolution. Vietnam was a country that had a a great deal of dependence on France as the colonising power


ary ew hy

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impermeable/impervious — a condition of material such as soil or rock that does not allow, under normal conditions, the movement water; for example the texture or structure of the soil or rock may prevent water movement. Under some conditions rock may have an impervious texture that does not allow the movement of water through it but the structure of the rock with fractures may mean the rock is permeable (see permeability) incised meander — a meandering river may flow slowly to the sea flanked on either side by a wide floodplain. For some reason the river experiences rejuvenation – it gains more energy. This may result from sea level becoming lower or the land through which it flows rises. Since the river now has more energy it cuts down (or incises into the land) forming deeper and steeper walled valleys. These are called incised meanders (see meander) income elasticity — a measure of people’s demand for products/services as their income levels change index numbers — numbers or indices used to show relative change in a set of statistics rather than the actual number involved in the change. The value of a particular year (the base year) is chosen. How other values vary from this value in terms of percentage difference is then determined. For example suppose in 1985 the population of an area was 1200. In this case, 1985 as the base year is given as the index number of 100. If an array of data indicates that 1990 has a population of 1320 the year 1990 is given an index number of 110 indicating that 1990 has a population 10% more than the 1985 figure. An index number of 90 indicates that the population is 90% of (or 10% less than the 1985 figure) indigenous — native to an area; not introduced (see exotic) indigenous people — original inhabitants of the land (also known as aborigines). Indigenous people include: • Koori — Australia

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• Maori — New Zealand • Inuit — Greenland, northern Canada, Alaska, Aleutian Islands • Yanomami — within various parts of the Amazon Basin • Maasai — East Africa eg Kenya • Ainu — Hokkaido, Japan • Penan — East Malaysia (Sarawak) (see page 90) indurated (or induration) — the hardening of materials such as soil as a result of pressure from overlying materials and cementation as a result of the addition of types of minerals. In soils such as podsols an indurated layer (or horizon) may form as a result of the accumulation of iron minerals. This is called a hardpan (see eluviation, illuviation) industrial agriculture — a type of commercial agriculture where crops undergo a number of mechanical processes (eg plantation crops such as coffee and rubber) industrial inertia — the state of a firm whereby it stays in one location when the initial reason for that location has disappeared, or a firm fails to adopt new strategies/technologies which may be to its benefit industrialisation — the growth in manufacturing / industrial activity in a region, a country or the world. The process of industrialisation can begin from a largely agricultural base where there is an increasing use of machinery in factories; industrialisation can also be seen with an already industrialised country adopting more advanced forms of technology such as computer technology. Industrialisation is commonly associated with the growth of the service sector as labour-saving techniques are used such as the use of robotics – less labour is often required in manufacturing with a shift in labour growth to the provision of services such as within the finance sector and education infant mortality rate — the number of deaths of infants in the first year of life per 1000 births. For example between

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1990 and 1995 the infant mortality rate in Mali (Africa) was 159 whereas in Australia it was 7 infiltration — the downward movement of water through the Earth’s surface. The rate of infiltration depends on such factors as the vegetation cover, slope of the land, soil type and bedrock (see figure 32) informal sector — that part of the economy in which employment is officially less than full time; this

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includes the self-employed and parttime workers. The informal sector is relatively large in developing countries and has been expanding in developed countries as part-time workers are increasingly replacing full-time workers. The informal sector includes those illegal occupations as well as those occupations that do not pay taxes for work completed (see formal sector)

Some Indigenous Peoples of the World REGION

NAME

Canada and USA Inuit (northern Canada/Alaska); Haida, Tlingit, Kwakiutl, Bella Coola, Tsimshian, Nootka (Canadian west coast); Cree, Meti, Chipewyan, Blackfoot, Dene (central Canada); Innu, Cree (eastern Canada); Haudenosaunee (Canada/USA border); Nez Percy (NW USA), Navajo, Uti, Pueblo including Hopi, Keres, Zuni, Dine (SW USA); Crow, Cheyenne, Arapaho, Pawnee, Comanche, Oglala Sioux, Shoshone (the plains of the USA) Central America Mayan descendants – Lacandon, Yucatec; Aztec descendants – Huichol, Tarahumara, Nahua, Zapotec (Mexico); Maya (Guatemala), Miskito, Sumu, Rama, (Nicaragua); Lenca, Pipile (El Salvador); Kuna, Guaymi (Panama) Arctic and Europe Inuit (Arctic); Aleut (Alaska); Saami (Norway, Sweden, Finland and Russia) South America Quechua, Aymara (highland Peru, Bolivia and Ecuador); Mapuche (Argentina and Chile); Tukano, Xavante, Yanomami, Parakana, Kayapo, Makuxi (Amazon Basin, Brazil); Amarakaeri, Amuesha, Tukano, Panare, Sanema, Shuar, QuichuA, Ufaina (Amazon Basin, Ecuador, Bolivia, Peru, Colombia, Venezuela) East Asia and Russia Tibetan, Uighur (China); Mongolian (Mongolia); Ainu (Japan); Yuit, Kazakh, Saami, Chukchi, Nemet (Russia) Africa Tuarg, Fulani (Sahara, Sahel); Dinka, Nuer, Shilluk (southern Sudan);San Bushmen (Angola, Botswana, Namibia); Maasai(Kenya, Tanzania); Oromo, Somali, Tigrayan, Eritrean (Ethiopia); Mbuti, Efe, Lese (Zaire, Cameroon, Central African Republic) South Asia Naga, Santal, Gond, Kameng, Lohit, Dandami (India); Pathan (Afghanistan, Pakistan); Vedda (Sri lanka) Chittagong Hill Tract Peoples (Bangladesh); Southeast Asia Karen, Kachin, Shan, Chin, (Burma); Karen, Hmong, Lisu (Thailand); Penan, Kayan, Iban (Malaysia); Kalinga, Ifugao, Hanunoo, Bontoc, Bangsa Moro (Philippines); Dayak (Indonesia – Kalimantan); West Papuan including Asmat, Dani (West Papua); Mae-Enga, Dani, Tsembaga (Papua New Guinea) Oceania Aborigines (Australia); Maoris (New Zealand); Kanak, Hawaiian, Tahitian, Chamorro (Pacific Islands) Source: Burger, J, The Gaia Atlas of First Peoples, 1991, p18-19

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informational city — a node for information flows through high technology media where large sections of the labour force work in such occupations as banking, insurance and legal services infrastructure — the materials in place to support the effective functioning of a community. Infrastructure includes water and power supplies, road and rail transport networks as well as communication systems such as telephone and computer information transfers inselberg — a large isolated hill surrounded by an eroding plain. They rise above the general level of the plain because they tend to be of a more resistant rock type than the plain or are the remains of a long period of backwearing across the plain with only the inselberg remaining. Inselbergs occur in such rock types as sandstone and granite. Uluru (Ayers Rock) is an example of an inselberg in situ — a term associated with a rock, soil or fossil being located in its original place of deposition or formation. For example “the soil material has formed in situ”; ie is the soil material has formed at this place and has not been transported from elsewhere by wind or water insolation — radiation received from the Sun. INcoming SOLar radiATION insolation weathering — the disintegration of rock in response to heating and cooling as it expands during the heat of the day and contracts during the cold of the night (see physical weathering) intensive farming/agriculture/land use — land use, agriculture or farming requiring a high input of capital, such as machinery and fertilisers, within a relatively small area of land. Dairy industry is an example of intensive agriculture that uses a high input of capital (expensive computerised machinery), modern technology (scientific breeding techniques) and a small area of land. This compares to the more extensive

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forms of agriculture such as beef cattle grazing that requires very large areas of land (see extensive farming/agriculture/land use) interculture — see intertillage INTERFET — the international force in East Timor. After East Timor’s vote for independence from Indonesia, in 1999, the UN Security Council implemented a peace-keeping force following much civil disturbance. INTERFET forces included Australia (the largest component with over 400 troops), USA, Britain, Canada, Philippines, France Thailand and New Zealand interfluve — the ridge separating two rivers. The interfluve marks the boundary of the catchment of a river (see catchment area) intergenerational equity — in terms of ecological sustainability this is best expressed in Principle 3 of the Rio Declaration: The right to development must be fulfilled so as to equitably meet developmental and environmental needs of present and future generations (see intragenerational equity) interglacial period — a warm period between ice ages. During the Pleistocene ice age the cold glacials were separated by warmer interglacials. The present Holocene in which we live is an interglacial interlocking spurs — topographic features produced as a river follows a winding or meandering course in its valley (Figure 33 colour). As a result of erosion, the land slopes relatively gently from the interfluve to the inside of a meander bend while the outside of the meander bend tends to have a much steeper slope. This is due to undercutting of this slope by the river. As the river meanders in its valley, avoiding high ground or resistant rock, a series of these spurs can be seen interrupting the view up and downstream intermittent stream — in terms of streams, stream that flow only part of The New Geography Dictionary

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the year, for example immediately after rain internal drainage — most rivers flow to the sea from higher land. However there are places where rivers flow to a low point in the land such as a lake. Lake Eyre in South Australia is an area of internal drainage. Here rivers such as the Diamantina River and Coopers Creek flow into the lake (at 10 metres below sea level) International Date Line — 180° longitude international division of labour — a term used to describe the global division of production between various countries. This tends to lead to countries or regions specialising in a particular type of production or stage in the production process. Such specialisation of production is largely influenced by the power and decisionmaking of large corporations International Geophysical Year — during a 30 month period – July 1957 to December 1959 – over 70 nations undertook a program of cooperative research with a focus on the Earth and its environmental systems. Out of the IGY came the seeds for the development of the Antarctic Treaty International Law of the Sea — first drafted in 1982 this international treaty establishes national sovereignty over marine resources lying within coastal waters. Beyond the immediate coastal waters the treaty identifies an Exclusive Economic Zone – a 200 nautical mile limit that gives the maritime nation the initial right to resources (eg fish stocks) within this zone International Monetary Fund — an agency of the United Nations that provides funding especially to developing countries in short term financial crisis International Union for the Conservation of Nature — see IUCN and World Conservation Union intertidal — between the low and high tide marks (see tides)

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intertillage — also called interculture this refers to the practice of growing two or more crops on the one area of land at the same time. However planting and harvesting are timed so that such activities do not necessarily fall at the same time intertropical convergence zone — an area of low pressure around the Earth located near the equator. The ITCZ is characterised by high humidity and high rainfall. The northeast and southeast trade winds blow towards the low pressure area of the equator. Convergence and uplift leads to heavy rainfall. The ITCZ is not in a uniform location around the world. It tends to meander (or wander) north and south of the equator extending further north and south where land occurs because of the greater heating capacity (and therefore convection) in these areas. Similarly the ITCZ moves slightly north and south of the equator with the seasons. In the Southern Hemisphere summer the ITCZ moves to around latitude 5–10°S while in the Northern Hemisphere summers it moves to approximately latitude 10–15°N. In this way the ITCZ can be experienced with the onset of the Monsoons (eg in the Southern Hemisphere’s summer over northern Australia; and in the Northern Hemisphere’s summer over south and Southeast Asia) intervisibility — the ability to see an object between two points such as on a cross section. If for example, on a cross section you can draw a horizontal line between two points without the line touching the cross section drawn, then in real life you would be able to see one point from the other — there is clear visibility between the two points intragenerational equity — when used in terms of ecological sustainability this means fairness and justice in resource use for all people of a particular generation (see intergenerational equity)


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intrazonal soil — well-developed, or mature soils, that reflect the significance of local soil-forming factors such as parent material, slope,

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drainage and vegetation – rather than climate as with zonal soils. Examples include saline soils in poorly-drained arid or coast areas and the bog soils

Figure 34 – The distribution of island arcs in the Pacific Basin and a cross section across an island arc

Source: C. Ollier, Volcanoes, Australian National University Press 1969 pp144-145

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reflecting the accu-mulation of decaying vegetation or peat in swamp environments (see bedrock) intrusion — the name given to the process whereby magma within the earth invades existing rock. The magma associated with the intrusion solidifies below the Earth’s crust and becomes what is called intrusive rock eg granite (see extrusion) inundation — the flooding of an area such as a river breaking its banks and flooding (or inundating) a town. After heavy rainfall rapid runoff across slopes can lead to rivers rising quickly. The river may overflow its banks and inundate the area covered by its floodplain invasion and succession — i) the movement of people from one area to another replacing a pre-existing population. One group of people, for example a particular age group, ethnic group or religious group may move into a residential area and over time, replace an existing group. This tends to occur over a long period of time such as 10, 20 or 30 years (see gentrification); ii) the process of the gradual invasion and eventual plant succession by a new plant community; for example a small shrub community being replaced over time by a taller tree community (see plant succession, sere) inversion — a condition of the atmosphere where the temperature either increases with height or is constant over a specific given distance (eg 10 m, 100 m, 1 km). Temperatures typically decrease with height allowing warmer less dense air to rise through it. In some circumstances the temperature change is inverted where a layer of cold air lies beneath warm air. In this case air is trapped in lower layers – as seen in times of fog close to the ground and pollution trapped above cities unable to ‘break through’ the inversion (see environmental lapse rate, adiabatic lapse rate)

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IPCC — Intergovernmental Panel on Climate Change irrigation — the addition of water to an area over and above normal amounts eg additional water added to crops irrigation salinity — a type of secondary salinity also known as wetland salinity; salinity due to excessive irrigation. Under normal conditions the water table is deep below the surface (eg 3 metres). In many semi-arid areas, such as southern NSW and NW Victoria (Australia), Israel and SW USA, people have introduced types of agriculture such as rice farming. These activities require a large input of water via irrigation. By adding water to the land the water table rises to the surface bringing with it the natural salts in the soil. These salts are then concentrated in the water. When used by farmers downstream who repeat this process the water becomes very saline (saltier and saltier) contributing to rising production costs and reduced crop yields (see dryland salinity) island arc — a line of volcanic islands arranged in an arc reflecting the shape of the ocean trench beneath them (Figure 34). Subduction has occurred with islands the result of volcanic extrusion. The Islands of Indonesia and the Aleutian Islands are examples isobar — lines joining places of equal air pressure shown in figure 55 (see hectopascals) isobath — lines joining places on the seabed of equal depth (see contour line) isodemographic map — a type of map drawn that shows a country’s size in proportion to its population isodapane — in economic geography a line joining places of equal total transport costs. The calculation of these lines provides a firm with information on total productions costs and can act as a guide to locating a firm in a particular area


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isohyet — an isoline which joins places of equal precipitation isoline — a line that joins places of equal quantity eg contour line and isohyet isopleth — any line that represents a particular quantity where everything on that line represents the same quantity. A contour line, an isobar and an isohyet are isopleths isostacy — the mechanism whereby the Earth’s surface rises or subsides as a result of the different weight, or density, between two bodies. The less dense materials that make up the continental crust ‘float’ on the denser mantle below. The same process explains isostatic adjustment during the last glacial period where the Laurentide ice sheet in North America, and the Scandinavian ice sheet in Europe weighed the continents down and forced much land below sea level. At the end of the glacial period the ice sheet melted, the weight of the ice was relieved so the land rose slowly back

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up to adjust to the shifting weight. This isostatic rebound is still occurring in northern Europe today isotherm — isoline which joins places of equal temperature isotropic surface — a surface such as land which has uniform characteristics in all directions such as flat land and the uniform distribution of natural resources. Isotropic surfaces are assumed in many location theories of geographic phenomena. This includes accounting for the distribution of settlements in W. Christaller’s central place theory (see Christaller, W.) isthmus — a narrow strip of land with water on both sides connecting two pieces of land eg Panama Canal ITCZ — see intertropical convergence zone IUCN — International Union for the Conservation of Nature and Natural Resources — now called the World Conservation Union IWC — International Whaling Commission

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J

jebel — an Arabic name for a mountain or hill in an arid environment — as in Jebel Marra in Sudan, Africa jeepny — in the Philippines a converted and much modified jeep left behind by American troops after World War 2 jet stream — a name given to the narrow belt of very fast winds in the upper atmosphere, between 7.5 km and 14 km altitude moving at speeds of 45 m per second. The subtropical jet stream occurs at approximately latitude 30° North and South of the equator and the subpolar jet stream between latitude 40° and 60° North and South of the equator joint — a natural fracture in a rock. Joints can occur in sandstone along bedding planes or even in igneous rocks where cooling, during the time when magma solidified, led to natural ‘shrinkage cracks.’ Joints are very different to faults. With joints there has been no movement either side of the joint. With a fault either side slides or has slid passed the other (see figure 6 colour)

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jökulhlaup — glacial meltwater released as a flood when volcanic activity under the ice heats and melts the ice – such as magma rising to the surface, heating the ground at depth and partially melting an overlying glacier. As the pressure of the water builds up it is eventually released as a sudden flood joule — a unit of energy junta — a self-appointed body that has taken over a normally elected government following a coup d’état Jurassic — a period of geologic time, within the Mesozoic era, extending from approximately 150–210 million years before present (see geological time scale, figure 27) just-in-time (JIT) — a system of production in which all necessary inputs of production, such as labour, raw materials and transport, are delivered just in time to meet production targets and deadlines. It is especially adopted as a management strategy for small production runs juvenile water — water brought to the surface or added to underground water by rising magma


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rynew geography dictionary ewgeography dictionary new hydictionary new geography

K

K2 — the second highest mountain in the world, at 8598 m, second to Mt Everest. K2 is also known as Mt GoldwinAustin and is also found in the Himalayas kame — a mound of roughly stratified sand and gravel laid down by streams flowing from, or off, the toe of a glacier kampong — a clustered rural settlement that was a village outside of the city but has been swallowed up as the city has grown outwards. This is common in Southeast Asian cities especially in Malaysia. They are typically of one-storey and the tenants of these kampongs own the land (unlike squatter settlements) with their own gardens, vegetables and fruit trees and fish breeding areas kang — in China, a bed with a stove beneath it heated by burning straw, soft coal or dry animal manure karren — an exposed limestone surface that has been weathered via solution forming grooves/furrows on the surface karst — limestone country sometimes marked by caves and subsurface rivers. Karst areas have formed on limestone rock that is weathered at a relatively rapid rate by the weak acids in rainwater and surface water. The Nullabor Plain in South Australia and Western Australia is an example of a karst landscape where there are no surface rivers — all are below the surface of the land (see doline, weathering) katabatic wind — downslope winds. Katabatic winds can be warm or cool. chinook and föhn winds are warm katabatic winds. Cold katabatic winds are common in areas of steep slopes

where a pool of cold air accumulates at a high altitude. This cold dense air flows downslope; for example the cold winds flowing off the Antarctic ice cap from the interior and the cold winds of winter flowing down the Hawkesbury valley within the Sydney Basin, NSW Australia (see anabatic wind) Kata Tjuta — formerly known as The Olgas (see figure 35 colour) Kayapo indians — indigenous people in the Amazon rainforest, South America Kelvin scale — a temperature scale that indicates 0º Kelvin as –273ºC. 0ºK is also known as absolute zero kettle — a depression in the land formed as a result of the melting of ice beneath the surface key — part of a graph which explains what the symbols and shading used on the graph represent kharif — the name given to the Southwest Monsoon (summer) in India and to crops grown in this season (see rabi) kibbutz — a rural settlement in Israel based on collective farming and communal villages. The ownership of the property and all profits are communal and the work on the settlement is shared among the inhabitants Koppen, Wilhelm — a climatologist who in 1920 provided a classification of world climates. He selected what he considered to be the most appropriate indicators, temperature and annual precipitation values. This was the first attempt to incorporate both temperature and precipitation. His classification was based on the global patterns of vegetation distribThe New Geography Dictionary

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ution that had then been recently published. His scheme includes five main divisions: A hot, moist climates B dry climates C warm, moist climates D cool, moist climates with snowy winters E cold climates Kow Swamp — a famous archaeological site in northern Victoria, Australia. It was the site of a skull that was much larger or robust than the Talgai skull and that of Mungo Man at Lake Mungo. This suggested that there may have been two subspecies of Aboriginal people that entered Australia during the Pleistocene kraal — a native hut village in southern or central Africa; also an enclosure for livestock in southern or central Africa Krakatoa — a small volcanic island between Sumatra and Java in Indonesia. Krakatoa began to erupt 20 May 1883 with major explosions 26 and 27 August 1883. One explosion was the loudest noise on Earth, and could be heard in Australia 4800 kilometres away. Although the northern face of the volcano (600 m altitude) was blown off there were no immediate casualties. However 36,000 people

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died on the islands of Java and Sumatra as a result of the tsunami that was produced kraznozem — a deep (more than one metre), red-brown soil typically developed on volcanic rock such as basalt. The texture of these soils tends to show a gradual change through the soil profile, such as from upper clay loams to deeper light clays, with no distinctive boundaries or horizons. The red colour is derived from the abundant iron oxide. These soils are very fertile as are most volcanic soils and are common on the south coast of New South Wales. Here rich pasture supports a dairy industry – (see residual sites) krill — a small crustacean found in the waters surrounding Antarctica — also known as Antarctic Shrimp Kung-she — a collective farm in the People’s Republic of China (see collective farming, commune) Kutikina Cave — located in Tasmania this is thought to be the southernmost occupied site in the world during the last glacial period 20,000–15,000 years ago Kyoto Convention — an international convention held in Kyoto, Japan, December 1997 with the aim of setting global and national targets for greenhouse gas emissions

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L

labour intensive — refers to production where a large work force is used rather than machinery. Many people are used in traditional rice padi in Southeast Asia. This is an example of labour intensive agriculture (see capital intensive, intensive farming/agricultural/land use) lacustrine — related to lakes lag industries — those industries that do not undergo growth due to selfinitiative or internal forces (such as implementing new technologies) but rather rely on the expansion elsewhere in the economy lagoon — a body of water between the land and the sea separated by land formed from the deposition of sediment such as sand by the action of waves. Bays are often cut off from the sea when a sand spit develops across the bay. The bay then becomes a quiet lagoon lahar — volcanic mudflow laissez faire — a theoretical economic system in which there is complete freedom in the flow of goods and services with prices determined by supply and demand Lake Baikal — located in far eastern Russia Lake Baikal is the world’s deepest lake at over 1.6km deep and containing approximately 18% of the world’s fresh water Lake Mungo — a dry lake in southwestern New South Wales. Lake Mungo is a significant archaeological site (figure 36). It was once part of the Willandra Lakes system when lake levels were full approximately 30,000 years ago. The area was much wetter

than it is now with 20 metre deep lakes abundant with native fish. Lake Mungo provides evidence of early Aboriginal occupation in southeastern Australia. A full skeleton dated at approximately 26,000 years old provides the oldest evidence of ritual cremation in the world with the body of Mungo Man carefully arranged in a grave and adorned with red ochre. Lake Mungo is now part of the Willandra Lakes World Heritage Site (see Kow Swamp, figure 39) Lake Titicaca — located in Peru and Bolivia (South America) Lake Titicaca is the highest lake in the world at 3810 metres above sea level land breeze — a local breeze blowing from the land to the sea, especially at night, as a result of differences in air pressure. During the night and especially in the early morning the land cools down appreciably, thereby causing air above it to have a relatively high pressure. However the sea remains relatively warm as it can retain its heat that it collected during the previous day. The air over the sea therefore has relatively low pressure. Since air moves from areas of high pressure to areas of low pressure, a wind blows from the land to the sea (see air pressure, sea breeze) landcare — as a result of deteriorating environmental quality, such as soil erosion, salinity habitat loss, the Australian Government established Landcare Australia in 1989. It attempted to draw attention to the plight of the natural environment, promote ecologically sustainable practices and to encourage community groups and others to become active participants in ecologically sound practices.

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The 1990s was declared Decade of Landcare and many groups have emerged supporting a Landcare ethic. Urban Landcare groups engage in weed control, water quality monitoring and bush regeneration (see ecological sustainability) land consolidation — a type of land reform where small parcels of land are combined or amalgamated into larger parcels land degradation — the reduction or deterioration in the quality of land.

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Soil erosion, soil salinity and deforestation are examples of processes that contribute to land degradation (see quoquake) landform — any natural feature of the Earth’s surface having a distinctive shape such as a plateau, slope, valley or mountain range land invasion — an urban invasion, common in Latin America, whereby prospective squatters occupy a piece of land in order to erect shelters landlocked — a state, country or

Figure 36 – Climate and lake levels at Willandra Lakes, NSW

Source: J. Flood, Archaeology of the Dreamtime, Collins1983, page 43

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catchment area that has no direct access to the sea. Landlocked countries include Rwanda, Zimbabwe and Chad in Africa, and Austria, Switzerland and Slovakia in Europe. The Aral Basin is a landlocked catchment area (see internal drainage) land reclamation — the treatment of an area to increase the area of productive land. Land is reclaimed, for example, by filling in land with various types of wastes (this is sometimes called landfill) land reform — changing the character of land ownership such as amalgamating small land holdings into larger units or breaking up large landholdings into smaller units. Land reform may also lead to a change in the system of land tenure (see land consolidation) LANDSAT image — an image taken from a satellite called LANDSAT which was launched in 1975. LANDSAT provides images of the Earth’s surface with a resolution of 30 metres (see SPOT, remote sensing) land system diagram — a diagram drawn to summarise landform patterns in an area. For example, an area may show a series of arid plateau areas all with steep escarpments covered with low forest and wide lowland plains with dried up salt lakes. Instead of drawing all of these, a land system diagram simply shows these three related landform types and associated biophysical character to give an impression of the recurring patterns that can seen in that environment land tenure — land ownership, such as freehold tenure, where a person or family owns the land or leasehold where a person rents (or leases) the land from a landowner land use — the way the land is used eg agricultural land use where land is used for various types of farming such as dairy cattle, wheat or sheep La Niña — an event that occurs due to the upwelling of abnormally cold water in the central and eastern Pacific

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Ocean while sea surface temperatures become warmer in the western Pacific. As a result of the warmer conditions in the western Pacific more intense low pressure areas form over Indonesia and northern Australia and widespread flooding occurs in eastern Australia (see El Niño) Lapp — common name for the indigenous people of Scandinavia (see Saami) lapse rate — see environmental lapse rate latent heat — heat stored in water molecules (often called hidden heat). As solar radiation is absorbed by water molecules this energy is used in the process of evaporation. Upon cooling this energy is released when condensation occurs. When air rises it cools at the (dry) adiabatic lapse rate (about 6.5°C per kilometre) the temperature of the parcel of air falls and condensation occurs; latent heat is then released into the atmosphere making the air warmer and so more buoyant. The air rises still further as can be seen in thunderstorms lateral erosion — erosion on the banks or sides of features such as rivers. The energy of a stream wears away and transports material downstream. Lateral erosion of a stream has the effect of widening the stream as well as leading to the stream migrating across its floodplain in the case of many meandering streams (see meander) lateral moraine — sediment that has been transported by a glacier and accumulated along the sides of the glacier (see medial moraine) laterite — a deep, red soil rich in iron and aluminium oxides but poor in silica. Such soils are commonly, but not only, found in tropical and subtropical areas where high rainfall leads to the leaching out of many minerals such as quartz (silica). Only the fine infertile iron-rich clay remains behind. The high temperatures and rainfall ensure that weathering of parent The New Geography Dictionary

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material (bedrock) occurs deep below the surface leading to many of these soils being more than 10 metres deep. In more temperate latitudes such as eastern Australia laterites are common where parent material is rich in iron minerals and the topography providing a warm moist (sheltered) microclimate. In other circumstances red, iron-rich soils have been described as ‘lateritic’ such as over sandstone bedrock. A climatic reason for the occurrence of laterite in this case does not have to be invoked. The influence of geology can be equally important where iron-rich bedrock can lead to these soils (see duricrust) latitude — the number of degrees a place is north or south of the equator eg, 20°S (see figure 37) Laurasia — the landmass that broke off from the northern part of the supercontinent of Pangaea, approximately 300 million years ago (see continental drift, Gondwanaland) lava — molten material that is extruded from a volcano or fissure within the Earth’s crust. Because of its different composition of gases molten material beneath the Earth’s surface is called magma (see aa, extrusion, pahoehoe, volcano)

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leachate — a term to describe the accumulated material that is the result of leaching of minerals through the soil. Another kind of leachate is that which results from the accumulation of liquids such as oils, paint and paint thinners and organic decomposition in waste disposal sites. This type of leachate is very damaging if it finds its way to waterways because an enormous amount of dissolved oxygen is used up from the water to break down the leachate. So much dissolved oxygen can be used up that the stream, for example, can become an aquatic desert as aquatic life dies through lack of oxygen leaching — the downwards movement of material in solution through a soil profile. This is very different to eluviation (see figure 53) leasehold land — land that is owned by groups such as governments, commercial organisations and individuals but is leased (rented) back to people or organisations. People or organisations leasing this land do not own the land; they are said to have leasehold tenure (see freehold tenure, land tenure) lee or leeward slope — the sheltered side of a hill or mountain. A slope that receives most rainfall or the greatest percentage of wind is called the windward slope. With winds app-

Figure 37 – Latitude and Longitude

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roaching the eastern side of the Eastern Highlands, Australia, the western slopes are described as leeward slopes because they are protected from the easterly winds (see rainshadow) legend — part of a map that explains what the various symbols used on the map represent Leptospermum — a shrub or small tree commonly referred to as a tea-tree levee bank — a sand deposit along the bank of stream resulting from the deposition of sediment during overbank flow or flooding liana — a long, thick vine, especially in rainforests, that winds around the canopy and can hang down towards the ground (Figure 38 colour) life expectancy — the number of years that a person can expect to live. Access to health services and better nutrition contribute to a greater life expectancy in many developed countries than in many developing countries. For example life expectancy in Australia is approximately 78 years for males and 84 years for females compared to 39 years for males and 42 years for females in Ethiopia (Africa) Some Examples of Life Expectancy Worldwide Region

Years

World Africa Europe North America South America Asia Australia

65 53 73 75 69 65 80

Example from region Sierra Leone 39.0 Hungary 69 Honduras 56 Bolivia 59.5 Afghanistan 43.5

light industry — manufacturing concerned with the light weight /volume raw materials and the output or production of a light weight/volume product. Examples include furniture manufacturing, textiles and computer production (see heavy industry)

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lignite — commonly known as brown coal (see bituminous coal) lignotuber — a woody structure, consisting of buds that sprout from the base of a tree when the upper part of the tree has been damaged or destroyed by fire limestone — a sedimentary rock composed largely of calcium carbonate. An example of limestone is rock produced from accumulated coral. Limestone landscapes include those dominated by caves as slightly acid water dissolves and then removes the calcium carbonate of these rocks. Jenolan Caves, NSW and The Nullabor Plain, Western Australia and South Australia are Australian examples of limestone areas (see dolomite , karst) limnetic vegetation — referring to freshwater lakes and ponds linear — relating to a line such as a linear scale or linear settlement pattern (see ribbon development) linear sprawl — development that occurs along important transport lines such as highways leading away from the centre of an urban area (also ribbon development) line of best fit — a type of trend line. This is a straight line and when it is drawn the sum of the spacing between the dots plotted on one side of the line should be the same as the sum of the spacing on the other side of the line. In many instances this can be done visually by estimating the trend shown by the plotted data lithify — turn to stone lithology — relating to the large-scale characteristics of rocks lithosphere — the Earth’s crust and upper mantle that includes soils, landforms and bedrock. The thickness of the lithosphere varies greatly. The oceanic lithosphere is relatively thin and extends for approximately 6–10 kilometres. The continental lithosphere is much thicker extending over 20 kilometres beneath the continents (see sial, sima) lithosere — plant succession that has developed from a rocky surface

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Little Ice Age — a change in climate between 1590 and 1850 that saw a cooling of 1ºC over much of Western Europe. During this period glaciers advanced by up to one metre per year littoral zone — the near shore zone; the seafloor area lying between the high and low tide marks (see sublittoral zone, supralittoral zone) loam — a relatively rich, friable soil containing a relatively equal mix of sand and silt and a smaller proportion of clay — hence the expressions loamy soil and loamy texture (see soil texture) local relief — the difference between the highest point and lowest point in an area or along a transect (see relief) loess — a soil that has formed from the deposition of wind-blown dust. The two common sources of this dust are i) from desert areas where dust is blown from the unconsolidated sands; and ii) in areas where winds tend to be

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strong in the outer areas of glacial landscapes and even periglacial areas. Wind has blown the fine sediment that was deposited by glacial meltwater forming thick layers of loess in areas such as western China longitude — the number of degrees a place on the Earth is east or west of the prime meridian (0°) (see figure 37) long profile — the path taken by a stream bed along its course from its headwaters to its mouth (see graded profile and thalweg) longshore drift — the movement of sediment, such as sand, along the coast. When waves approach the beach the swash moves up the beach at an oblique angle; the return flow of water is at right angles to the beach. In this way sand is able to move along the beach in a zigzag movement. Longshore drift can lead to the loss of

Figure 39 – Cross section (A) and a plan view (B) of the Lake Mungo lunette, Willandra Lakes, NSW

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sand from one area of the beach and the accumulation of sediment at another such as to clog the mouth of any stream entering the sea. As a result of this wave movement, a longshore current is set up along the coast. This longshore current can lead to depositional landforms such as sand spits (see backwash) Lösch, A — a German economic geographer (1906–1945) who further developed W. Christaller’s central place theory. Rather than central places being grouped on the basis of population size and function as proposed but Christaller, Lösch suggested that the most efficient settlement pattern was that showing the continuous progression in population size and number of functions (see Christaller, W) low income economy — those countries with a GDP per capita less than $750 eg India, Ethiopia and Vietnam (see high income economy, middle income economy) low order goods — in the study of population, settlement and economic geography, low order goods are those that are relatively cheap and those that people are not willing to travel long distances to buy. For example people will travel only short distances to buy a newspaper or a loaf of bread — these are low order goods (see high order goods) lower catchment — the area of the river catchment close to its outlet to the sea or lake

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low pressure cell — an area of low pressure consisting of closed isobars. In a low pressure cell the value of the isobars decreases towards the centre (ie the pressure decreases). In the Southern Hemisphere winds blow in a clockwise direction around a low pressure cell (see coriolis force, figure 26, high pressure cell, figure 55) lunar eclipse — this occurs when the Earth casts a shadow on the Moon as the Earth passes between the Sun and the Moon. Where the Moon is completely obscured this is called a total eclipse; when partially obscured it is called a partial eclipse. A lunar eclipse occurs only on a full Moon but not all full Moons (see solar eclipse) lunette — a crescent-shaped sand dune on the leeward side of a now dry lake (figure 39). Lunettes are composed of a mixture of quartz sand as well as clay. This sediment has typically accumulated on the downwind side of the lake. Lunettes are common in present day semi-arid areas such as in southwestern NSW, in the Willandra Lakes region, Australia. Lunettes formed as a result of fluctuating lake levels and eventual drying over a period lasting the past 50,000 years. One of these lakes, called Lake Mungo, records evidence in its lunette of early Aboriginal occupation as well as climates during the past 50,000 years (see figure 36)

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M

maar — a landform caused by a volcanic explosion and consisting of a crater which is generally at ground level and is considerably wider than deep. Typically a lake or pond forms in this depression (see volcano) maar lake — a lake in a volcanic crater Machu Picchu — these stone ruins of a 15th century Inca city are located at 3500 metres above sea level in the Peruvian Andes Mountains. The characteristic terraces show clearly the tremendous engineering skills at the time magma — molten rock beneath the Earth’s crust. When magma solidifies below the surface it forms igneous rock such as granite; when it solidifies above the surface it forms igneous rock such as basalt magnitude — a measure of an earthquake’s intensity. On the Richter scale, with magnitudes ranging from zero to ten, each increase in magnitude is ten times the intensity of the previous magnitude. Instruments can normally only detect a magnitude of 2 on the Richter scale; a magnitude of 5 leads to structural damage of buildings and a magnitude of 8 sees large buildings destroyed. However, the impact of a 2, 5 or 6 magnitude earthquake will be very different between areas depending on such features as underlying geology, soil type, slope, as well as the density and type of settlement structures. The Richter scale measures the amount of energy released by each shockwave produced by the earthquake. The Richter scale is a logarithmic scale. Each unit increases 106

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by 2.4 orders of magnitude (or a 240fold increase in energy). Very few earthquakes have exceeded 8.9 on the Richter scale majority world — also known as the developing world which comprises the great bulk of the world’s population (see developing country and minority world) mallee — scrub vegetation dominated by Eucalyptus species. The main vegetation community is that of dense low bushes (1–2 metres high) often with a sparse distribution of small trees (5–10 metres tall) — hence the term mallee scrub and mallee eucalypts. Mallee is typically found in the drier areas of southeast and southwest Australia maloca — a communal dwelling for families of the Yanomami people in Brazil; sometimes called a ‘longhouse.’ It is also used as a place for rituals and dancing. These malocas can be up to 50 metres in diameter and up to 20 metres high Malthus, Thomas — an English economist who, in 1798, argued that population growth cannot be sustained because of its rate of growth. He argued that because population growth increases exponentially and food supplies increase only at a linear rate population will be limited by the food supply available to it. Population numbers will be modified largely by forces such as disease and war. His thesis has been found to be false as modern technology such as genetic engineering is providing HYVs mammal — a vertebrate animal that feeds it young with milk created from mammae (nipples). With the exception of monotremes mammals such as kangaroos and koalas do not


ary ew hy

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lay eggs but rather give birth to live young Man and the Biosphere Program — an international program coordinated by UNESCO to develop a worldwide network of key biophysical regions and to identify their biophysical character. In this way the interactions between people and the biosphere can be identified and the need for management programs such as land restoration and wildlife conservation can be addressed (see biophysical environment) mangrove — any tree or shrub community where low trees are growing mostly in marshes or tidal areas. Being of the genus Rhizophora of the Rhizophoraceae they are characterised by many interlacing above-ground roots mantle — a zone within the Earth extending from between 20–70 km below the surface to a depth of nearly 3000 km. The mantle lies between the Earth’s solid crust and the Earth’s core.

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The mantle includes massive convection cells with heat generated by radioactive decay of minerals. These cells redistribute and drive the move of the crustal plates and associated continental drift (see plate tectonics) manufacturing — the making of goods. There are two types of manufacturing: • Processing — the changing of a raw material such as iron ore into steel, or bauxite into aluminium • Fabricating — the assembly of already processed materials into a finished product such as car assembly, furniture assembly map — a diagram using a variety of symbols representing part of the Earth’s surface usually drawn at a different scale map reference — (Figure 40) see grid reference and area reference map scale — see scale marble — metamorphosed limestone or dolomite (see metamorphism) marginal land — land that only just supports present land use or may only

Figure 40 – Map References

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just support a proposed land use. Any adverse effect on the land, such as drought or the increasing intensity of use, will lead to a response by that land in the form of land degradation making the use of that land uneconomic mariculture — the commercial growing of marine animals and plants (eg fish) maritime climate — the term used to describe conditions close to coastal areas. A maritime climate has a number of characteristics: • high total annual rainfall • small annual temperature ranges • small diurnal temperature ranges maritime zone — the area of the sea or ocean surrounding land subject to national or international law. Some states claim exclusive access to surrounding waters for use of seabed resources. Beyond these maritime zones are the high seas market area — the size of and the area served by local markets market town — centres of exchange; these are typically collection and distribution centres for local products marram grass — a type of grass (Ammophila arenaria) commonly found on coastal sand dunes. Its rhizomes and roots extend for many metres. As a result marram grass is used extensively for dune stabilisation to minimise erosion marsupial — mammals having no placenta and supporting their young in a pouch eg a kangaroo, koala and wombat. Most of the world’s marsupials are found in Australia. However most of Australia’s fauna are placentals Marxism — a system of thought developed by Karl Marx: i) used in urban geography to explain that the urban geography of capitalism is the outcome of the relationship between political and economic forces within society; and ii) used in development geography to explain that class struggle is the main agency of historical change

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mass movement — the downslope movement of earth materials such as soil under the influence of gravity and typically lubricated by water. Examples of mass movement include soil creep and landslides Maunder Minimum — a period in Earth history between 1650–1700 when there was virtually no sunspot activity. This period coincided with what as been called the Little Ice Age in Europe (see sunspots, ice age) MDB — see Murray Darling Basin mean — see arithmetic mean mean deviation — a measure of the dispersion in a set of statistical data indicating the extent to which individual scores deviate from the arithmetic mean. It is calculated by summing the absolute deviation of all scores from the arithmetic mean then dividing by the number of scores mean deviation = Σ| x-x | n where | x-x | = the absolute difference between each value (x) and the mean ( x) Σ = the sum of all of these values n = the number of scores meander — a natural bend in a river. Meanders are more common downstream and are the result of the processes of erosion and deposition along its course (add incised meander) meander scroll — a depositional landform, typically within a river’s meander belt that reflects the previous position of the meandering channel. As a river migrates across its floodplain its abandons its previous levee deposits normally parallel to the main channel. These meander scrolls can be seen as sandy ridges on the floodplain (see figure 25, levee bank) medial moraine — sediment that has accumulated in a line at the centre of a glacier as a result of the joining of the lateral moraines of one side of two glaciers (see moraine) median — in an array of statistical data, arranged from the lowest to highest


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score, the median is known as the ‘middle score’ mediterranean climate — a climate that has wet winters and dry summers. Countries that have a Mediterranean climate include those of southern Europe (eg Italy and Greece). Mediterranean climates are also found in southern Australia such as the Barossa Valley in South Australia megacity — a very large city typically with a population exceeding 10 million people (eg Mexico City, London and Sao Paulo) megafauna — more than 15,000 years ago giant marsupials roamed eastern Australia. From about 80,000 years ago these giant marsupials were part of the Australian environment. For example there were the Diprotodons – wombat-like but the size of a rhinoceros; the Procoptodon – a three metre tall kangaroo; and the carnivorous Thylacoleo – known as the marsupial ‘lion’ (the size of a leopard). The period 25,000 to 15,000 years ago was a time of environmental upheaval in eastern Australia associated with continental drying, declining water supplies, and vegetation changes. At the same time another change occurred; the increased use of specialised weapons and of fire employed by Aboriginal hunters. These all threatened Australia’s megafauna. It is much debated as to the cause of the megafauna’s extinction. Three possible causes singly or in combination were responsible • climate change associated with the drying of the Pleistocene ice age • overkill by hunters as a source of food in an expanding population • habitat loss via firing by Aboriginal people (see carnivore) megalitre — one million litres, or 1000 cubic metres (also written as ML) megalopolis — a very large continuous built-up urban area usually over about 15 million people. Examples include

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Tokyo, New York and Mexico City. The term was first applied to the BosWash region in the USA taking in Boston, New York and Washington Melanesia — that area of islands to the immediate northeast of Australia such as Papua New Guinea and the Solomon Islands Melanesian — short, dark-skinned people with frizzy hair who occupy the islands to the northeast of Australia (see Melanesia) meltwater — water that flows as a result of the melting of glaciers or snow fields mental map — a map of the environment that a person has in his or her mind. The representation of the environment will be very different to more formal maps such as topographic maps. The image that a person has of an area will be influenced by the person’s experiences of, and attitudes to, that area Mercalli scale — a scale between 1 and 12 used to indicate the strength of an earthquake based on the amount of damage the earthquake does (see Richter scale) Mercator projection — a map projection of the Earth which represents landmasses in their correct shapes but distorts their areas. For example, Australia and Greenland appear similar in size where in fact Australia is more than three times the size of Greenland – 7.6 million km2 compared to only 2.1 million km2) meridian — a line of longitude; eg the prime meridian; the 20°E meridian of longitude metabolic heat — heat generated from within the body metamorphism — in geology, a process where a rock or mineral changes such characteristics as its composition, structure and texture, as a result of the application of heat and pressure. As a result of overlying pressure beyond normal burial and often over one kilometre, rocks can change their character — for example limestone

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can change to marble. An igneous intrusion may rise through the crust and heat the surrounding rock. The minerals in these rocks can be changed – for example mudstone into slate (see igneous rock) mesa — a flat-topped hill. Mesas indicate that erosion has been relatively rapid horizontally (because it is narrower than a plateau). The surface of a mesa often has a more erosion-resistant duricrust. A mesa tends to be wider than a butte (see figure 20) mesosphere — an area of the Earth’s atmosphere extending between approximately 50 km and 80 km altitude. The temperature within the mesosphere increases with height (see figure 2) mesophyte — a plant that grows in conditions that are neither very wet nor very dry (see Hydrophyte and Xerophyte) methane — a gas that occurs in the atmosphere (CH4). Methane is produced from a number of sources such as agriculture (rice padi and ruminant animals such as cows); the Arctic tundra as permafrost melts due to global warming; gases released from decomposing material from municipal tips. Methane has been increasing rapidly (just like carbon dioxide) reflecting the growth in population numbers. Methane is a major greenhouse gas metropolitan area — the suburban area surrounding the commercial core of a city — made up mostly of the residential area of the city Mezzogiorno — the poorer agricultural south in Italy M.I.A — Murrumbidgee Irrigation Area (NSW, Australia) microclimate — the climate of a small area. The climate of the large area around us might be described as arid. However there may be a sheltered valley where the slopes provide shade and therefore cooler temperatures and there may be a permanent stream

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at the bottom of the valley. The valley is said to have a microclimate that is very different from the environment around it micron — one thousandth of a millimetre (or a millionth of a metre) Micronesia — the very small islands in the western Pacific north of Melanesia. These islands include Guam, Truk and Palau Mid-Atlantic Ridge — a long linear ridge (or mountain chain) under the Atlantic Ocean with North America and South America to the west and Africa and Europe to the east. One of many ocean ridges, this ridge forms the constructive boundary of ocean plates either side of it. Along the ridge magma rises to the surface, spreading and creating new ocean floor. The island of Iceland is being split apart as the ridge passes through it. Evidence of this includes much volcanic and earthquake activity on the island (see figure 17, mid-ocean ridge, plate tectonics) midden — a garbage or refuse heap. In areas of coastal Australia early Aboriginal communities disposed of shellfish and the skeletons of fish in middens especially at the entrance of some caves such as in Royal National Park and Botany Bay National Park, NSW, Australia middle income economy — countries with a GDP per capita greater than $750 but less than $9500 eg Russia, Brazil and Indonesia (see high income economies, low income economies) mid-latitudes — those areas between approximately latitude 20°–40° north and south of the equator (see latitude) Mid-ocean Ridge — a line of connected volcanoes – fissures forming a mountain chain under the sea, the result of the separation of plates and the upwelling of magma. The midocean ridges are said to be constructive plate boundaries, the plates spreading sideways and ultimately ‘consumed’ at subduction zones (destructive boundaries) (see


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figure 17, continental drift, East Pacific Rise, Mid-Atlantic Ridge, plate tectonics, volcano) Milankovitch, M — in 1920 Milutin Milankovitch performed a range of calculations which showed that the Earth’s position in space, its tilt and orbit around the Sun, all change in a regular manner. He claimed these changes affected incoming solar radiation and produced three cycles of 96,000, 42,000 and 21,000 years (see Milankovitch cycles) Milankovitch cycles — these are cycles showing variations in the Earth’s orbit around the Sun and rotation on its axis. These are used to explain the cause of glacial periods in the Pleistocene. The position of the Earth relative to the Sun changes over time thereby affecting the receipt of insolation. There are three cycles: • changes in the eccentricity of the Earth’s orbit (every 96,000 years) – the Earth has an elliptical orbit around the Sun (rather than circular) so the length of seasons

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varies over the years. As a result insolation increases or decreases • changes in the precession of the equinoxes (every 21,000 years) – this means that the time of year that the Earth is closest to the Sun (perihelion) varies • changes in the obliquity of the ecliptic — there is a variability in the tilt of the Earth’s axis from 21°39' to 24°36'; the greater the tilt the greater the difference between summer and winter These cycles are synchronous with the advance and retreat of ice during the Pleistocene milieu — the atmosphere created by the total surroundings and felt or experienced by those people within it. The milieu created by a rainforest environment is very different from that created by an alpine environment; just as the milieu characterised by a community of a particular ethnic origin is very different from that of another origin

Figure 41 – Misfit Streams

valley walls valley walls

meandering stream meandering stream

Underfit Stream of the Osage Type

Manifestly Underfit Stream

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millionaire city — a city with more than one million people minority world — also known as the developed world which compromises only about 35% of the world’s population (see majority world) misfit stream — a stream whose channel is smaller than the valley in which it flows (Figure 41). The stream channel may follow the same pattern as the valley within which it flows; this is called an underfit stream of the Osage type. Where there are meanders within a valley meander, this is called a manifestly underfit stream (see underfit stream) mode — in a set of statistical data the mode is the most common or most frequently recorded score mode of production — the organisation of social relationships underpinning economic activity, the production of surpluses, and the reproduction of social life.

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Capitalism and feudalism are examples of modes of production Moho — (also called the Mohorovicic Discontinuity) the boundary between the Earth’s crust and the underlying mantle. Because of the different depths of the continents and the oceans, the Moho is approximately 40 kilometres below the continents and 10 kilometres beneath the oceans monoculture — the growing of a single crop. A farm may be concerned with just wheat, maize or cotton. A typical example of monoculture is a plantation where a single crop is developed such as rubber, or tea (see commercial farming) monopoly — (i) a market where there is only one producer eg one producer of a type of shoe; (ii) the situation where a person or organisation has sole control of a feature eg an organisation has a monopoly on the sale of a type of battery

Figure 42 – Monsoons

SCALE: 1

112

CM

= 900

KM

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monotreme — any egg laying mammal comprising of the Duckbilled Platypus and the Echidna (of which there are two species) monsoon — a condition of the atmosphere whereby air pressure systems and wind patterns are reversed between summer and winter (Figure 42); the monsoon can be described as a seasonal reversal of winds. For example a low pressure system forms in summer over northern Australia and a high pressure system forms over Asia (their winter). Winds blow from the north over Asia, picking up moisture over the waters of Southeast Asia, making northern Australia very wet. In winter over central and northern Australia an area of high pressure forms whereas in Asia (their summer) an area of low pressure forms. Winds then blow from the arid areas of the central Australia making northern Australia dry. The result is a seasonal climate characterised by wet summers and dry winters (see general circulation) monsoon climate — characterised by wet summers and dry winters montane — referring to a mountain environment; relating to, growing in or inhabiting mountain areas Montreal Protocol — in agreement, initially signed by 27 countries in Canada in 1987, to limit the production of Ozone depleting CFCs moraine — sediment that has been eroded, transported and often deposited by a glacier (see deposition, erosion, glacier, lateral moraine, medial moraine) morbidity — a value which expresses the frequency of disease or illness in a population moratorium — to temporarily stop a course of action morphology — in urban geography the character or physical form of an urban centre. The morphology of an urban centre may describe the different land use types, transport facilities and

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architectural style within that centre. The morphology of an urban centre can change over time as seen with effects of urban consolidation as well as urban decay and urban renewal mortality — an expression that gives an indication of the frequency of death within a population mountain — a major landform on the Earth’s surface that extends over 600 metres above sea level. Mountains are typically of high altitude with steep slopes showing a distinctive altitudinal zoning of climates and vegetation Mt. Pinatubo — a volcano in the Philippines that erupted in June 1991 killing more than 300 people. The 2km-wide crater produced ash that covered an area of nearly 1000 km2 with ash circling the globe in the stratosphere for three years mulga — the name given to a type of scrub vegetation in the drier interior of Australia dominated by acacia (wattle) species multilateral agreement — an agreement between a number of nations (see bilateral agreement) multilateral aid — see foreign aid multiple land use — a system of land use and resource management that provides for different land use types in the one area (eg mining and grazing) multiple nuclei model — a model of the internal structure of cities (Figure 58). Developed by the geographers E.L. Ullman and C.D. Harris the model is based on the premise that urban growth occurs around separate nodes or nuclei. A particular area may attract financial and commercial functions typical of a CBD and through the process of agglomeration. Other functions such as industrial and residential activity are attracted to sites around these nuclei. As a result the land use pattern can be seen as comprising one or more discrete areas of a land use type around these nuclei (see concentric zone model, metropolitan area, sector model)

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multiplier effect — any economic activity generated indirectly from services and industry dependent upon a major development Murray Darling Basin — the basin or catchment area made up of two major rivers – the Murray River and the Darling River and their many tributaries covering an area of approximately 1.02 million square kilometres or 1/7 of the Australian continent. The northern extent of the

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basin lies in southern Queensland and reaches the sea at Lake Alexandrina in South Australia. The rivers drain an important resource of Australia. The land supports a wide range of agricultural land use such as sheep grazing, beef cattle and dairy cattle grazing and crops such as a wheat, corn, and maize mutualism — where two species live together and both derive benefit M.Y. — million years

ne ge di


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new geography dictionary geography dictionary new dictionary new geography

N

nadir — the point in space directly opposite the zenith (ie at 180°). The point directly above an observer at 90°N is called the zenith; the point at 90°S is called the nadir nation — a group of people with a shared culture and experience within a particular area — in many cases within country borders but often this is not the case. For example, there are over 500 nations in the Americas National Conservation Strategy — an Australian Government response, in 1983, to the World Conservation Strategy. The NCS has three objectives: i) to maintain and improve the quality of ecological systems; ii) to maintain genetic diversity on the planet; and iii) to ensure sustainable use of ecosystems as well as flora and fauna. Landcare is part of the National Conservation Strategy national estate — those places and features of the natural and cultural environment that have special value such as aesthetic, historic, social or

scientific significance to the present community and future generations. nation state — the political unit of people living in a defined territory, with government authority in their economy, political organisation and external affairs (NSW Board of Studies) NATO — North Atlantic Treaty Organisation natural disaster — any natural event, such as an earthquake, tropical cyclone or bushfire, where there is a significant loss of life or property natural hazard — any natural event such as an earthquake, tropical cyclone or bushfire where people see a perceived risk in terms of life or property (see natural disaster) natural increase — (of population) the increase in population by subtracting the number of deaths from the number of births natural resource — an element, or feature, of the biophysical environment that has actual or perceived value to people. Examples of natural

Death Tolls from Natural Disasters 1960 to 1987 Hazard DeathToll Largest Event and Date Tropical Cyclones 622,360 East Pakistan (Bangladesh) 1976

Death Toll 500,000

Earthquakes

497,600

Tangshan, China 1976

Floods

36,300

Vietnam, 1964

250,000 8000

Avalanches and Mudslides

3002

Peru, 1987

25,000

Volcanic Eruptions

27,459

Columbia, 1985

23,000

Tornadoes

4500

East Pakistan (Bangladesh) 1969

540

Snow, Hail and Windstorms

3078

Bangladesh, 1986

300

Heatwaves

1000

Greece, 1987

400

Source: E Bryant, 1991, Natural Hazards, Cambridge University Press 1991, page 126

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resources include water, forests, minerals, soil and wilderness (see renewable natural resource; nonrenewable natural resource) nautical mile — 1.852 kilometres neap tide — the rising tide (see tides) neighbourhood — an urban district occupied and dominated by an identifiable subculture to which most people conform neocolonialism — a term describing the tendency of a powerful developed nation gaining economic and/or political influence (control) over an independent developing country. For example the influence of developed countries in the newly emerging nations of the Southwest Pacific and east and west Africa neotectonics — the study of landforms affected by recent earth movements also called morphotectonics (see plate tectonics) net migration — The difference between immigration and emigration. This may be positive or negative indicating population growth or population decline network — a general term, which describes the multiple number of pathways, joined together eg transport network, food web New International Economic Order — the mid-late twentieth century saw increasing economic and social disparities between so-called developed and developing countries. A group of developing countries demanded a new international economic order be set out formerly by a United Nations declaration in 1974. It ‘called for the replacement of the existing international economic order, which was characterised by inequality, domination, dependence, narrow selfinterest and segmentation, by a new order based on equity, sovereignty, equality, interdependence, common interest and cooperation among States irrespective of their economic or social system’ (the) new urbanism — a sentimental vision of the past relying on history to

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provide a method of ensuring community identity in the present. The concept is a reaction to globalisation. At its roots it is a reflective moment based on nostalgia – attempting to escape from the isolation of modern urban life and the complexity and pace associated with globalisation newly industrialised country (NIC) — a county that has recently experienced rapid industrialisation since the 1960s and 1970s after previously being considered an economically less developed country. Examples of NICs include those of Southeast Asia such as Taiwan, South Korea and Malaysia. NICs have been characterised by increasing average annual incomes and producing relatively cheap export goods due to low labour cost NGO — non-government organisation NICs — see Newly Industrialising Countries niche — the space that an organism inhabits and to which it is adapted. A niche provides the food for the organism as well as the microenvironment that ensures its survival. Environments such as the Tropics provide a greater range of niches than say deserts because of the abundant energy in the Tropics. Should the niche be disturbed in some way such as by fire, the invasion of a competitor, or a natural change such as increasing aridity, the niche for an existing organism may be destroyed and another organism may occupy this new environment or niche to which it is adapted nickpoint — part of the long profile of a stream that changes its gradient rapidly. For example as a river erodes its bed it may produce what is called a graded profile whereby erosion and deposition equal each other at any one point. However if a more resistant bedrock is encountered the river may cascade over this forming a waterfall and erode its bed further down stream. Similarly a nickpoint may also occur where the stream changes its


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long profile due to local uplift or sealevel change NIEO — see New International Economic Order Nitmiluk National Park — that area of the Northern Territory that includes Katherine Gorge nitrogen cycle — the circulation of nitrogen through the biophysical environment mainly as a result of living organisms. Inorganic nitrogen (in the atmosphere) is taken up by plants, which in turn are eaten by animals and eventually returned to the soil and water. Nitrogen fixation leads to nitrogen being taken from the air and being available to plants. Some bacteria return nitrogen to the atmosphere nitrogen fixation — a reaction between nitrogen and the atmosphere where atmospheric nitrogen is incorporated in a soluble compound such as water and is available as a plant nutrient. (Legumes such as peas and beans ‘fix’ nitrogen and make it available to the soil as a fertiliser nival — relating to snow nivation — the process of freezing and thawing in an environment dominated by snow — especially in glacial and alpine areas node — a focus for any type of activity. For example towns and cities act as nodes whereby major roads and railways focus on the urban centre; investment capital, labour, and goods and services are drawn to the urban centre such as Sydney, Perth, Newcastle and Geelong nomad — a term commonly used for a person who moves from one place to another especially in arid and semiarid areas. For example nomadic herders such as the Bedouin who move camels or cattle from place to place in North Africa and the Middle East (see arid environment) non-renewable natural resource — the total amount of the natural resource is reduced as a result of its use. Fossil fuels are non-renewable resources because when oil, coal or

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natural gas as well as various minerals are consumed the total amount of that resource is reduced. The consumption of non-renewable natural resources has been increasing at an increasing rate, especially in developed countries in order to provide power for transport and industrial growth NPWS — National Parks and Wildlife Service NSW, Australia nuclear winter — a theory that suggests that a thermonuclear war would lead to global cooling of over 20ºC. The resulting fires, smoke and other particulates in the atmosphere would have the effect of shielding the Earth’s surface from sunlight — thereby cooling the atmosphere, the oceans and the land. This, in turn, would lead to a major global extinction event nucleated settlement — a compact rural settlement consisting of groups of buildings in close proximity. These may be small farmsteads or homes and shops around a central point such as a church or community centre. More broadly a nucleated settlement is any dense settlement in an area surrounded by a low density hinterland. In many cases nucleated settlements locate at a point that provides the greatest advantage for the settlement – such as at the junction of two roads or two rivers for ease of trade, or on a top of a hill for defence nuée ardente — a cloud of very hot gas and ash that moves downslope produced during some volcanic eruptions. The ash is later deposited to form what is called tuff nunatak — a mountain peak protruding through an icecap. In Antarctic, for example, the two kilometre icecap covering many mountains has the peaks of some mountains rising through and above the icecap (eg the peaks of the Transantarctic Mountain Range in Antarctica) Nunavut — a new territory in northern Canada created 1 April, 1999 when the Northwest Territories were divided into two. Nunavut means ‘one land’

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new geography dictionary geography dictionary new dictionary new geography

o

oasis — a fertile or wellwatered area within a desert with animal and plant life sustained throughout the year obsidian — volcanic glass formed from lava that has cooled extremely quickly occluded front — because a cold air mass moves faster than a warm air mass the passage of a cold front tends to move forward and replace warmer air. As the warm air is less dense than the cold air the cold air tends to ‘squeeze’ (or force up) the warm air ahead of it to higher altitudes. The cold air mass may then ‘catch up’ with cold air ahead of it. Where these two cold fronts meet leads is called an occluded front — the result of the process called occlusion oceanic crust — that part of the Earth’s crust under the oceans. It is much thinner than continental crust, at about 3 kilometres thick (see sial, sima) ocean trench — a deep submarine valley that forms along the line where one lithospheric plate plunges under another in what is called a subduction zone. Ocean trenches can be seen around the word especially around the Pacific Ring of Fire. Ocean trenches are the sites of many active volcanoes and severe earthquakes. The Mariana Trench, east of the Philippines, is the lowest point on the Earth at 11,022 metres below sea level – where the Pacific Plate moving west is plunging under the Philippine plate (see figure 17, continental drift, plate tectonics) OECD — Organisation for Economic Cooperation and Development. Member countries are Australia,

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Austria, Belgium, Canada, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Japan, Luxembourg, Mexico, Netherlands, New Zealand, Norway, Poland, Portugal, South Korea, Spain, Sweden, Switzerland, Turkey, United Kingdom, USA okta — a unit for measuring total cloud cover. One okta indicates that one eighth of the sky is covered by cloud; three quarters of the sky is indicated by six oktas. Oktas are sometimes indicated on synoptic charts old growth forests — forest dominated by mature trees that show little or no evidence of human disturbance such as logging and road building. Old growth forests such as the Eucalypt forests in southeast New South Wales and the rainforests in north Queensland have been the focus of many disputes; for example i) loggers wanting timber for building construction in Australia ii) multinational companies wanting woodchips as a cheap source of timber product and iii) conservationists wanting to retain these to provide natural habitat as well as a resource for future generations (see woodchipping) old population — the population of a community, such as a country, is considered ‘old’ if the proportion of young people ( under 15 years of age) is less than 30% of the total population AND the proportion of older people (over 65 years old) is greater than 6% of the total population (see ageing population) oligopoly — an industry in which a few firms control the production process (see monopoly)


ary ew hy

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oligotrophic — poorly-nourished waters such as some lakes and rivers Olympic Dam — uranium mine 200 kilometres north of Port Augusta, South Australia. Beginning operations in 1988 it is also known as Roxby Downs omnipolis — an urban area dominated by shopping malls. Super-regional centres try to reproduce facilities traditionally available in the central business district. The omnipolis caters for a 'global culture' as well as a tourist market. The local 'sense of community' declines the larger the mall. The focus of the super-regional centre is typically on recreational shopping and entertainment rather than traditional retail services omnivore — organism that eats both vegetable material and meat. Humans are omnivores Onchocerciasis — river blindness; very common in West Africa such as in Burkina Faso. Onchocerciasis is caused by people being bitten by a black fly, with tiny worms skewering into the body and attacking the backs of the eye (see Schistosomiasis) OPEC — Organisation of Petroleum Exporting Countries open cut mining — also called strip mining; occurs when material such as coal or ores such as gold and bauxite are mined by removing the soil overburden (Figure 43 colour). Often seams are subjected to explosions to make them accessible for collection and transport. Open cut mining is used when the material is not in rich veins – in these circumstances, direct shaft mining is undertaken opportunity cost — the alternative that is foregone (or given up) as a result of taking up an alternative option. For example the construction of an elevated walkway across sand dunes may incur an opportunity cost of not being able to begin a dune revegetation program

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optimum range — where an organism lives within only a small prt of their range of tolerance. The organism can survive outside this range but the organism would be under stress. Conditions of temperature, moisture, food source and predation ensure survival organic farming — farming without the use of artificial fertilisers, herbicides and pesticides. Vegetable growing is carried out using inputs such a direct rainfall and sunshine. This method of production can be described as labour intensive orogeny — or orogenesis; the process of mountain building. Mountains are typically formed at plate margins such as fold mountains at sites of plate collision and volcanic mountains at subduction zones. The types and characteristics of mountains are influenced by six main factors: • rock sequences such as sedimentary deposits in geosynclines • structural deformation such as the amount of folding or faulting that has occurred in a sequence • metamorphism, ie the changed temperature and pressure rocks are subjected to that can lead to changing mineralogy and rock type (such as shale to slate) • igneous activity such as the upwelling of magma forcing land to rise, including the upwelling of magma in subduction zones and at hot spots • erosion or the various forces of degradation wearing away mountain landforms • isostacy as the land ‘rebounds’ following the removal of overlying material by erosion (see fault, fold, plate tectonics, sedimentary rock, volcano) orographic rainfall — rainfall that results from orographic uplift. For example as air moves from the sea toward the land the air cannot pass through higher land so it rises up to a higher altitude. The New Geography Dictionary

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As the air rises, it cools and may eventually rain. Rain falls on the windward side of the barrier (ie the side from which the wind comes). On the other side of the barrier (on the lee or leeward slope) conditions are much drier (see precipitation, figure 50) orographic uplift — air that is forced to rise as a result of meeting a barrier. orthogonal — imaginary lines that are drawn at right angles to wave crests showing the concentration of wave energy. These lines showing energy distribution are concentrated on headlands and less so in bays and along beaches. This is one explanation for major erosion along cliffs and deposition along beaches orthophoto map — a composite map incorporating imagery from aerial photography as well as overlying contour lines. Although not totally accurate in locating features they do provide insight as to relationships between air photo images and the topography as indicated by overlain contours (see figure 69 colour) Our Common Future — ‘Our Common Future’ is a publication that arose out of an international meeting held by the WCED and published in 1987. It had the aim of raising global consciousness as to the plight of global natural resources as well as the disparity in the quality of life of people around the world. It begins by saying: ‘The Earth is one but the world is not. We all depend on one biosphere for sustaining our lives. Yet each community, each country, strives for survival and prosperity with little regard for its impact on others. Some consume the Earth’s resources at a rate that would leave little for future generations. Others, many more in number, consume too little and live with the prospect of hunger, squalor, disease and early death.’ It concludes: ‘The commission is

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convinced that if we can make solid progress towards meeting these principles the next century can offer a more secure, more prosperous, more equitable and more hopeful future for the whole human family’ (see World Commission on Environment and Development) outstation — an Aboriginal settlement developed in more remote areas than townships and reserves that they were accustomed to. Since the early 1970s some Aboriginal groups have decided to live in independent communities, in northern and central Australia, attempting to retain traditions and develop a more independent lifestyle. These communities have come to be known as homeland centres or outstations overbank flow — river flow that leaves the main channel reaching the floodplain as in a flood overland flow — the movement of water across the surface of the land. Water flows across the surface because the land has become saturated. The rate of precipitation has exceeded the rate of infiltration (see Horton overland flow) overurbanisation — where cities in developing countries experience population growth that outstrips economic growth and leads to major social, environmental and economic problems oxbow lake — a river landform that forms when a section of a meandering stream is cut off from the main channel – also called a billabong or a meander cutoff (see meander) oxidation — a process of chemical weathering. The absorption by a mineral of an oxygen atom. Oxidation is common in rocks containing iron minerals. In soils iron minerals are oxidised when they absorb oxygen dissolved in water passing through the soil. An example of oxidation can be seen in the rusting of objects containing iron


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ozone — a form of oxygen that consists of thee oxygen atoms (as opposed to the normal 2 needed for people to breathe). In the lower atmosphere ozone is toxic to people especially those with asthma. Ozone (O3) however is beneficial to life on Earth where it is concentrated in the stratosphere, 22–25 km altitude. Here it filters damaging ultraviolet light from the Sun ozone hole — a region in the stratosphere (22–25 km altitude)

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where there has been a thinning of ozone concentration. Initially detected over Antarctica it has spread to be over southern Australia and southern South America and more recently a hole has developed over the Arctic. It is thought that the ozone hole has developed as a result of the excessive use of chlorine compounds in refrigerants, foam packaging and aerosol cans. The resultant CFCs attack ozone thereby making it thinner and less able to act as an umbrella against insolation (see

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new geography dictionary geography dictionary new dictionary new geography

P

Pacific Rim — those countries that border the Pacific Ocean such as Japan, the Philippines; USA, Peru and Chile Pacific Ring of Fire — a line of volcanic and earthquake activity around the edge of the Pacific Basin (Figure 44). It includes the area from the Aleutian Islands in the north, south through SW USA and Central America and along the Andes mountain range in South America; as well as the area north from New Zealand, through the Solomon and Indonesian islands and north through the Philippines and Japan. In these areas, such instability is the result of major plate movements at subduction zones (see continental drift, plate tectonics, plates, volcano) padi (also paddy) — i) rice; ii) the small field in which rice is traditionally grown in Asia (see padi field) padi field — a small field in which rice is grown in flooded fields typically in Asia (see intensive farming/agriculture/ land use, padi) pahoehoe — solidified lava with a smooth or ‘ropy surface.’ This is very different from the sharper, more angular surface of aa lava (see volcano, extrusion) pallid zone — the white or very pale soil horizon within a weathered soil profile. It often indicates that strong leaching has occurred with only fine gained clays remaining in the horizon (see chemical weathering, weathering) palynology — the study of pollen grains used to identify particular vegetation species. Such analysis is also used to determine earlier climatic conditions. For example, from the study of sediments, pollen indicating rainforest 122

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type plants in a present arid environment suggests that the climate was much wetter and possibly warmer than today (see figure 12) pampas — a name for the grasslands of Argentina, South America (see savanna) pan — see hardpan and podsol Panama Canal — an 82 kilometre canal opened in 1914 in Panama linking the Atlantic and Pacific Oceans. The canal allows shipping, both for recreation and international trade, to use this route rather than the much longer route south around Cape Horn (South America) pandemic — a worldwide or continentwide outbreak of an infectious disease. It is an epidemic that affects many countries at once Pangaea — the name given to the single continental land mass of approximately 250 million years ago that eventually split into two ‘supercontinents’ (200–180 million years ago) – Laurasia comprising presentday northern hemisphere continents and Gondwana comprising the present southern hemisphere continents, and India (see continental drift) parallel — a line of latitude; eg the 50°S parallel of latitude (see longitude) parent material — the material from which soil material has developed. Parent material may be the observed bedrock. A soil may form from the weathering of sandstone bedrock. In this case the sandstone is the soil’s parent material Paretian optimum — originally used in economics (by the economist Pareto) this is a concept that states that, with uniform incomes and stable levels of


ary ew hy

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technology in an efficient economy, it is not possible to increase one person’s or group’s consumption or satisfaction without reducing that of another person or group. This is similar to the concept of the sustainable yield of natural resources. As a result of the

consumption of natural resources there is an impact of such consumption on either the environment or on individuals. The Paretian optimum is that point where it is not possible to increase the level and rate of consumption of a resource without having an adverse effect on

Figure 44 – Pacific Ring of Fire

Eurasia JF Ar

In

Phil

Australia

Pacific

North America

Africa Cocos Nazca

South

Antarctica

Distribution of earthquakes and volcanoes (A) – note the high concentration around the edge of the Pacific Plate – (Ar=Arabian Plate; Source: T.H. Van Andel, New views on an old planet: a history of global change,

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other aspects of the environment or the community parna — clay deposits including some sand that makes up individual dunes or sheets of sand — typically deflated from unvegetated arid land and from the dry beds of salt lakes in Australia (see deflation) pastoralism — a form of agriculture that uses large areas of land for the grazing of livestock such as beef cattle with little or no cultivation of crops (see commercial agriculture, extensive farming/agriculture/land use pasture — grassland used for the grazing of cattle Patagonia — an arid area of south and southeast Argentina (South America) Paterson’s Curse — a plant, also known as Salvation Jane. Paterson’s Curse was introduced into Australia from the Mediterranean region in the 1800s. It has become a weed as it out competes native pastures and has invaded grazing lands that were used as a food source for cattle pathogen — a substance such as an organism that causes disease patterned ground — a general term used for an array of shapes that occur on the land’s surface as a result of a number of processes such as frost action. Typically soil particles are sorted according to grain size with shapes such as circles, stripes and polygons formed depending upon slope, soil type and even the availability of moisture. Various types of patterned ground are common in periglacial areas PCB — see polychlorinated biphenyl ped — a natural soil aggregate consisting of many soil particles. Peds can be arranged in a number of patterns including blocky peds 1–2 cm diameter, and columnar peds which are approximately 5 cm long pedal — soil material showing an organisation of soil particles into discrete aggregates. A pedal soil may show blocky peds. Soils with a clayey or loamy texture are often pedal in some form (see apedal)

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pediment — an extensive weathered rock surface (hundreds of km2) subjected to various types of physical weathering and eroded by deflation as well as a combination of rill erosion and sheet erosion. Steeper slopes are backed by a steep scarp. A concave-upward slope extends beyond the scarp to an extensive area of very low gradient (as low as 1° to 2°). Such slopes are common in far western NSW, and northern South Australia, Australia. Where a number of adjacent pediments coalesce the broad flat rocky plain is called a pediplain pediplain — see pediment pedogenesis — the formation of soils pedology — the scientific study of soils and soil material – their characteristics, distribution and processes of formation pelagic — relating to the open ocean Penck, W — whereas W.M. Davis, in his cycle of erosion, promoted the theory of slope decline leading ultimately to peneplain, Walther Penck advocated the idea of slope retreat. In this model it was suggested that slopes eroded backwards, rather than downwards. Relatively steep angles resulted leading ultimately to a gently sloping eroded bedrock surface called a pediment peneplain — an extensive area of low elevation and relief approaching sea level as a result of erosion. A peniplain is a result of what W. M. Davis suggested was the end product of a landscapes ideal (uninterrupted) cycle of erosion (see erosion) peninsula — a narrow piece of land surrounded on three sides by water; eg Cape York Peninsula Pepenadores — Mexico City’s poorest people who live on and feed from city garbage dumps percentage change — a mathematical measure indicating by what proportion (percentage) of the initial figure that a value has increased or decreased over a period.


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For example a value of 20 shows a 100% increase if it increases to 40; a value of 50 increasing to 150 shows an increase of 200% % change = the difference between the two values the original number x 100 eg in 1980 there were 5000 people living in Sunhillow; . . . but in 2002 there were 6500 percentage change = 1500 x 100 5000

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Similarly high altitude mountainous areas can be described as periglacial because similar processes operate in these cold environments (see mountain, physical weathering) perihelion — at approximately 3 January each year the Earth and Sun are at their nearest point (see aphelion) permafrost — permanently frozen soil. Permafrost is common in high latitude areas such as Canada, Northern Europe and Eastern Russia permeability — a measure of the capacity of a rock or soil to transmit a fluid such as water – hence highly permeable and low permeability (see impermeable/impervious) personal quality of life index — a measure of development/ personal well-being of a nation and individuals. The index uses three indicators: life expectancy, infant mortality and

Therefore there has been a 33% increase in population numbers perched water table — a water table located above the normal water table. Water collects above a relatively impermeable layer of rock strata. Below this is an unsaturated layer followed by the main water table (see impermeable/impervious) perennial — i) plants: live for more than one year ii) streams: Figure 46 – The Phosphorus Cycle: flows flow all year round (see between sources and sinks Australia-wide ephemeral, intermittent) periglacial — a term used to describe those conditions and landforms bordering on, or similar to, those of ice caps. A periglacial climate besides being arid (dry) has temperatures below 0°C for at least 6 months of the year. Periglacial processes are dominated by freeze-thaw action where rocks are broken up as a result of the pressures exerted by ice crystals expanding as water freezes. Solifluction on hill slopes results. Here soils become saturated with water as ground ice melts and the top layers of a slope slowly move down slope under the influence of gravity. Areas of tundra have been described as periglacial because of the cold Source: Commonwealth EPA, temperatures. The New Geography Dictionary

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literacy rate (see human development index, infant mortality rate) petrified wood — wood that has been turned to stone. As wood breaks down the tissue matter of vegetation such as trees, it is slowly replaced by minerals that are in the groundwater percolating through the soil – minerals such as calcium carbonate and silica. These minerals eventually crystallise assuming the shape and structure of the initial tree petroglyph — a prehistoric drawing or carving on rock (Figure 45 colour) pH — a measure of the acidity or alkalinity of a substance such as soil or water. pH measures the number of hydrogen ions in the substance. pH is the negative logarithm of the hydrogen ion concentration in a substance. pH is measured on a scale of 0–14 on which 7 is said be neutral. A number less than seven indicates relative acid conditions; greater than 7 relatively alkaline conditions. For example a pH of 4 indicates an acid soil — and it is ten times as acid as a soil with a pH of 5 phosphorus cycle — a major biogeochemical cycle of the Earth which describes the transfer of phosphorus within the biophysical environment (Figure 46). Part of major geological processes, operating over millions of years, phosphorus accumulates on the ocean floor forming phosphatic rocks. As a result of Earth movements, such as mountain building, these rocks become exposed at the Earth’s surface. Phosphorus is then broken down later to be taken up by plants and in turn by animals and people. Birds add phosphorus to the land in the form of guano. This occurs on the island of Nauru. Additional phosphorus is added by the input of fertilisers and sewage which, when leached into the soil, returns to the oceans via rivers and wetlands. The addition of phosphorus onto the land and into waterways causes serious

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problems for native vegetation and aquatic life (see degradation, eutrophication) photic zone — the surface waters of rivers, lakes and oceans that are penetrated by sunlight (see eutrophication) photochemical smog — a type of air pollution resulting from a variety of chemical reactions between sunlight and pollutants in the atmosphere. Photochemical smog commonly follows the occurrence of brown haze when, during the mornings, gases such as nitrogen and carbon monoxide are added to the lower atmosphere by car exhausts. These chemicals react with the more intense sunlight in late mornings and early afternoons to form a ‘chemical soup’ in the atmosphere. This can be very toxic to many people — such as people with asthma when ozone concentrations become very high photosynthesis — a biochemical process in plants by which energy from the Sun (used by chlorophyll), carbon dioxide and water are taken up by the plant. The plant produces more organic material and in doing so gives off oxygen CO2 + 2H2O light energy [CH2O] + O2 chlorophyll

photoperiodism — the response of plants and animals to variations in the relative length of day and night eg the timing of flowering or breeding physical geography — a branch of Geography concerned with the description and explanation of the natural features of the Earth’s surface. It includes the study of such features as rivers, coasts, soils, vegetation, weather and climate. Increasingly, the focus of physical geography has been to provide a better understanding of the Earth’s physical processes such as erosion and global warming in order to improve the wellbeing and quality of life of people (see geography, human geography)


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physical weathering — the physical breakdown of material into smaller pieces in situ. The combined action of wind, water and temperature results in such processes as abrasion, freeze-thaw action or thermal expansion. All lead to the reduction in the volume of the original material (see chemical weathering, weathering) phytoplankton — tiny marine plants (see plankton) pillow lava — lava that has solidified quickly under water and takes on the appearance of pillows (see extrusion, volcano) pingo — a small rounded hill typical of glacial and periglacial areas. The pingo has grown as a result of the development of the central ice core. They are found in areas such as northern and central Canada and northern Russia (see glacier)

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piping — a geomorphic (earth surface) process where throughflow is concentrated especially along a soil horizon boundary such as between the A-horizon and the B-horizon. When the soil horizon is exposed on a hillslope, along a steep stream bank, material drains out and is deposited downslope. This leaves a ‘hollow tube’ or pipe beneath the surface. If and when the pipe collapses, due to the absence of deep-rooted vegetation, gullies can form placental — a mammal where the young remain in the womb for much longer than marsupials and for which there is no pouch – eg bats and various rodents plankton — small microscopic freshwater and marine organisms. There are two main types; phytoplankton such as algae and zooplankton which include such

Figure 47 – Pleistocene sea level changes

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animals as protozoa. Plankton are an important food source in the marine ecosystem. They are also important in regulating global climate. For example, plankton are important photosynthesisers. They take up large quantities of carbon dioxide. However with further ozone depletion plankton will die and so take up less carbon dioxide. In turn, this could lead to further global warming (see photosynthesis) plantation — a large field for growing crops. A term commonly used for large ‘estates’ in tropical and sub-tropical areas where there is a high input of capital such as land, machinery and fertilisers and crops are grown for export overseas (eg pineapple, rubber, tea) (see commercial farming, intensive farming/agriculture/ land use, monoculture) plantation agriculture — an agricultural system engaged in the large-scale production of commercial crops. Originally plantations were established in developing countries following early colonisation by western countries especially along coasts and river valleys for easy export of crops. A system of agriculture was established that replaced traditional local food producing crops. Instead farms became amalgamated into single large estates called plantations typically concentrating on a single crop and with the use of scientific methods and close management. Nonfood crops included rubber trees and cotton. However many food crops were not for local production but for export to markets in the developed world — eg tea, oil palm, cocoa, pineapples and sugar cane plant succession — the progressive natural development of vegetation where one vegetation community is successively replaced by another. Primary succession begins at areas that have not been previously occupied by vegetation (eg a rock surface, a sand dune). Secondary succession occurs in areas where the present vegetation has

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followed the destruction of an earlier vegetation community such as by fire or land clearing due to urban sprawl plate tectonics — the science studying the movement of plates over the lithosphere as a result of sea floor spreading. This study has developed since the 1960s following the confirmation of the theory of continental drift (see Wegener, A) plates — pieces of the lithosphere on which ride the continents. There are 16 major plates the largest being the Pacific Plate. Australia (including Tasmania) and the island of New Guinea are on the one plate. This Australian Plate is drifting north at approximately 7cm a year (see continental drift, figure 44, plate tectonics) plateaus, plateaux — a large area of elevated land of uniform height. The land may extend for hundreds of square kilometres. Australian examples include the Woronora Plateau south of Sydney, NSW or thousands of square kilometres such as the Arnhem Plateau in the Northern Territory playa — a dry salt lake typically found in arid and semi-arid environments such as in Western Australia and South Australia (see arid environment, salina) Pleistocene Epoch — a period in the history of the Earth with marked temperature fluctuations (Figure 47). Within this period (sometimes called “the ice age”) there were major falls of temperature called glacials with warmer interglacial phases between (see Quaternary Period) plenilune — the time of the full moon plucking — a process of glacial erosion describing the removal of discrete blocks of bedrock. Weathering such as frost wedging weakens joints and bedding planes in bedrock which are plucked or pulled out by the action of moving ice plunge pool — a pool at the base of a waterfall marking a nickpoint in the long profile of a stream


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plural society — a society in which two or more distinctive cultural groups live side-by-side with no central political body governing the group as a whole. Religion, language and customs are practised by the individual groups pluvial — a period of wetter conditions as a result of either increased precipitation or decreased evaporation. This is often related to high lake levels in arid areas during the Pleistocene pluviometer — an instrument for measuring rainfall in millimetres pneumatophores — these are the vertical aerial roots of vegetation such as mangroves that protrude from larger roots under the ground. Where the roots are covered with water or covered during high tide. Pneumatophores allow the mangrove to take in carbon dioxide. They also allow the plant to give off waste has such as hydrogen sulphide (or rotten egg gas) podsol — a deep, sandy slightly acid soil. Developed often in stabilised sand dunes podsols reflect a history of

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vertical processes. Leaching of minerals and eluviation of fine particles produce a distinctive soil profile. The weak humic acid produced at the surface from the decay of vegetation leads to a distinctive shallow A-horizon. Below this horizon, however, minerals and fine particles have been transported through the profile leaving a bleached or white horizon which is commonly composed of individual quartz sand grains. Minerals such as aluminium oxide, stripped from the upper Ahorizon, are often illuviated in the lower B-horizon. In some instances a ‘hardpan’ or indurated horizon, develops. This horizon is an orangebrown hard, brittle layer that is difficult for roots to penetrate and sometimes needing a hammer to break (see illuviation) point bar — a deposit of sediment such as sand on the inside bend of a meandering river. Rivers flow more slowly on the inside of meander bends because of the slowing effect of friction as water rubs against the bank of the stream. As the river slows in

Figure 48 – World Population Growth

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Figure 49 – Population Pyramids

100+

WORLD

90 80 Age (years)

70 60 50 40 30

Males

Females

20 10 0

8

6

4

100+

2 0 2 4 % of total population

6

8

DEVELOPED COUNTRIES

90 80 Age (years)

70 60 50 40 30

Males

Females

20 10 0

8

6

4

100+

2 0 2 4 % of total population

6

8

DEVELOPING COUNTRIES

90 80 Age (years)

70 60 50 40 30

Males

Females

20 10 0

130

8

6

4

2 0 2 4 % of total population

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6

8

velocity its competence is reduced; the river then deposits the heavier sediment that it can no longer transport (see deposition , figure 25) point source — the specific location of a substance entering a drainage system (stream) Polar cell — part of the atmosphere’s general circulation, the Polar cell is located in the high latitudes over each pole. In the Southern Hemisphere, cold dense air over the South Pole sinks. It meets the surface and then flows north to approximately latitude 60°S. At this point it meets warmer, less dense air coming from the north. When the two bodies of air meet the less dense air rises through the troposphere. Some of this air then moves south again at about 8 km altitude. The air cools, becomes denser and so sinks again at the Pole. This circulation of air is known as the Polar cell (see General circulation, the Hadley cell and the Ferrel cell). This cold sinking air contributes to the extreme aridity of the polar region (see atmosphere, Ferrell cell, figure 26, Hadley cell) polder — flat low-lying land below sea level along the coastal areas of The Netherlands that have been reclaimed from the sea. Dykes have been constructed to hold back the sea as the land has been drained. This provides additional land for activities such as agriculture polychlorinated biphenyl — a group of chlorinated hydrocarbons that have been widely used in industry for example as insulators in


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transformers. The use of PCBs has been severely reduced as a result of the awareness of their toxicity to people and the environment generally as well as their prolonged lifespan within the environment Polynesia — that area of islands to the east of Australia such as Tonga, Samoa, Hawaii and New Zealand (see Melanesia, Polynesia) Polynesian — tall, brown-skinned people with dark, straight or wavy hair who occupy islands to the east of Australia (see Melanesia and Micronesia) pool — a long, deep and slow flowing section of a river. Pools are commonly found on the inside of meander bends (see figure 25, riffle) pool-riffle sequence — a series of deep sections (pools) and shallows (riffles) along the course of a river. Deep pools

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(with a low water velocity) are commonly found on the inside of meander bends and riffles (with a higher water velocity) along the straight reaches of a stream. It has been demonstrated that pools are separated by lengths equivalent to 5–7 channel widths. However this can vary widely. For example local field studies have shown that in some instances ‘long pools’ can alternate with ‘short pools’ with ‘long pools’ separated by as much as 10 channel widths and ‘short pools’ separated by as little as three channel widths. Pool-riffle sequences are a common bedform of both straight and meandering streams as rivers adjust to changes in discharge and sediment load Pope’s Line — a line drawn in 1498 north-south through South America as

Figure 50 – Types of precipitation: orographic, frontal and convectional rainfall

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a result of tension between early colonisers Portugal and Spain. These countries wanted the perceived wealth of South America. So the Pope drew an arbitrary line that almost follows the 55°W meridian of longitude. All the land to the east of this line was given to the Portuguese; to the west was for Spain population — a group of individual organisms of the same species occupying the same habitat (Figure 48). For example a penguin colony; the human race

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population density — the number of people per unit area of land. For example, if there are 5 people in a square kilometre of land the population density is said to be 5 people per square kilometre (or 5 people/km2); 100 people in 50 square kilometres of land = 2 people/km2. Population density tends to be high in urban areas (eg 200/km2) and lower in rural areas (eg 10/km2) population pyramid — a bar graph (histogram) showing via a series of horizontal bars the number or percentage of the population in a

Description of Common Types of Precipitation (hydrometeors)

PRECIPITATION Drizzle

DESCRIPTION

Droplets less than 0.5mm diameter; intensity usually less than 1mm/hr; very small numerous droplets that seem to float in the air following air currents. Mist is often interchanged with drizzle although it more specifically refers to a condition of reduced visibility due to microscopic water droplets in the air Rain Droplets greater than 0.5 mm diameter, intensity generally more than 1.25 mm/hr. Larger but fewer droplets than drizzle so that there is generally less reduction in visibility except for the heavier rainfalls Snow White or translucent ice crystals often agglomerated into the form of flakes. Size of flakes depends principally on water content and amount of moisture surrounding the crystal Sleet Transparent, solid grains of ice formed from freezing of rain or slight melting and refreezing of snow as it falls. Sometimes confused with small hail Hail Balls or lumps of ice often with concentric layers of clear and milky ice, diameter greater than 5mm. If the diameter is less it is called ice pellets or snow pellets Virga Water and ice particles falling from clouds but evaporating before reaching the ground Rime White or milky granular deposit of ice formed by rapid freezing of supercooled water droplets hitting an exposed surface Glaze Coating of clear smooth ice on exposed objects by the freezing of a film of supercooled water deposited by rain, drizzle or fog. Denser than rime Dew Water condensed on objects near the ground whose temperatures are above freezing but below dew point. Frost occurs if temperatures are below freezing. White dew is frozen dew resulting from temperatures falling below freezing after dew is formed Modified extensively from Maher, J.R., Climatology: fundamentals and applications, 1974 p.48

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particular age group cohort — see Figure 49. The shape of the population pyramid provides an idea of the character of the population. For example in developing countries the base of the pyramid (ie less than 15 years old) tends to be relatively wide (eg due to high birth rates). However, the top (greater than 60 years) tends to be very narrow (eg due to high death rates and low life expectancy) porosity — a characteristic of rock or soil indicating the extent to which it contains spaces (pores or voids) within it — strictly a measure of the percentage of the total volume of rock or soil that is pore space. Limestone may be very porous; granite is not post-Fordism — workplace practices and modes of industrial organisation that have developed since the mid 1970s featuring more flexible methods of production, such as just-in-time or subcontracting post-industrial city — a city with a substantial proportion of workers engaged in the quaternary sector postmodernism — a world in which individual entities are constructed (and reconstructed) from many cultural sources, where ethics and morality are developed through dialogue and choice, where no dominant style dominates art and culture and, where people feel free to cross cultural borders or cling to tribal identities in a globalised society post-structuralism — a philosophical movement that tends to reject the rational ideas of science and grand stories of social evolution. It is an economic development of the modern era and is open to a wide range of views of social enquiry prairies — grassland typical in central and western USA. Much of the prairies have been taken over by extensive farming such as cattle grazing (see extensive farming/agriculture/land use)

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Precambrian Era — a period of geologic time before the Cambrian Period. The Precambrian Era makes up the great bulk of geologic history extending from the formation of the Earth, 4.5 billion years ago until approximately 570 million years ago after which there was an explosion in the diversity of life from the Cambrian Period until the present (see geological time scale, figure 27) precious metal — a metal of high economic value such as gold and silver often used for and in jewellery precipitation — the process by which water returns from the atmosphere to the surface of the Earth in the form of rain, hail, sleet, snow, dew etc (Figure 50) precis — a summary; a precis map in Geography is used to summarise a single feature in an area eg vegetation, landforms, rivers pressure gradient — a term used to describe the rate of change in pressure across an area. A steep pressure gradient occurs where there is a rapid change in pressure; this can be shown where the isobars are close together. In this case winds tend to be strong. A gentle or small pressure gradient shows little change in pressure over an area so isobars are far apart and the winds are weak primary data — information that is firsthand and has not been processed or changed eg that collected through fieldwork such as surveys and field measurements primary production i) the production of raw materials provided by nature such as the mining of coal and iron ore, the raising of beef and dairy cattle and the growing of crops such as wheat and sugar cane ii) a measure of the energy or matter potentially available to heterotrophs. Estimates of global (net) primary production vary greatly

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but some are: Total volume – 180 x 109 dry tonnes of dry matter Ecosystem

Net Primary Production (grams / m2 / year

coral reefs

2500

tropical rainforest

1800

temperate forest

1250

open ocean

125

desert scrub

70

primary research — research undertaken that generates new information mainly from original fieldwork, such as measuring and recording. Similarly describing the changing pattern of a river channel, conducting an interview or implementing a community questionnaire are examples of primary research – rather than research that relies on data already collected and collated such as in newspapers or from statistical tables (see secondary research) primary sector — that sector of the economy concerned with agricultural production and mining primary succession — see plant succession primary treatment — the first stage in the treatment of sewage to remove large solid objects by screens and relying on the settling of sediment. A process of flocculation is used where an agent is used (called Alum), placed in the sewage treatment pond, attracting suspended particles to it and then settling out later to be removed (see secondary treatment, tertiary treatment) primate city — a city that is ranked 1 in an urban system (eg in a country) and is far bigger in terms of population than the second ranked city. Many African, central and South American and Asian cities are primate cities (eg Mexico City, Kinshasa, Lima, Jakarta and Bangkok). Countries with this characteristic are

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said to display a degree of primacy (see binary pattern, rank size, figure 57) primates — a group of mammals that first appeared more than 60 million years ago and which include lemurs, monkeys, apes and humans prime meridian — the line of longitude at 0° where other meridians lie either to the east or to the west (also known as the Greenwich Meridian) processing — see manufacturing Procoptodon — an extinct giant kangaroo in Australia (up to three metres tall). The Procoptodon was part of the megafauna that roamed Australia approximately 80,000 years ago producer services — services that are supplied to business or government (for example specialised legal or financial services) rather than directly to individual users of commercial services. Producer services are used to determine world city status property rights — the legal title to land (ownership). Property rights are legally enforceable and can be transferred such as through the sale of property (see freehold tenure, land tenure) proportional representation — a system of electing members of parliament whereby the number of elected members is proportional to the percentage of the total vote won by the party proportional symbols — symbols used on a map the size of which are proportional to the value they represent. Symbols may take a variety of forms. For example if trying to show that the population of City (B) is half that of City (A) then City (A) will have a symbol twice as large as that of City (B). However it is not as simple as this. Often strict formulas have to be used when drawing proportional symbols. For example if showing population by comparing the size of proportional circles City (A) will not have a circle


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twice as large as that of City (B); this is because it is the area of the circles that need to be proportional. To calculate the area of proportional circles: i) obtain the data (eg 100, 1000, 1500 people) ii) find the square root of each number (in this case 10, 32, 39) iii) convert to millimetres (eg 1mm represents 2 people) iv) this gives a scale for the radius of the circle v) draw the scale and key on the map vi) draw the circles on the map with a pair of compasses There are many different types of proportional symbols that can be used such as circles, rectangles and triangles; these can even be done three dimensionally protocol — a formal agreement between parties defining procedures and courses of action. The Montreal Protocol is an example Przewalski’s Horse — the only wild horse left in the world discovered in Mongolia over 100 years ago. Now found only in zoos, it is a species under serious threat of extinction psammosere — plant succession in a sandy environment such as on a sand dune psychrometer — a type of hygrometer that measures relative humidity. A psychrometer measures the temperature of a ‘wet bulb’ and the temperature of a ‘dry bulb’ and following a particular procedure relative humidity of a local site can be determined Ptolemy (Claudius Ptolemaeus) — a Greek geographer and philosopher who, approximately 2200 years ago, promoted the idea that the Earth was

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the centre of the universe. His ideas held sway for 1500 years until proven incorrect public goods — those items or goods owned collectively by the community such as parks, roads and libraries. These are typically provided by governments as part of the smooth and efficient functioning of the community public land — land owned or held by the government pueblo — a nucleated village or town in the altiplano region of Bolivia. The buildings consist of mud-brown adobe houses with clay-tiled roofs (see nucleated settlement) P-wave — a seismic wave within the Earth generated by an earthquake due to movement in the Earth’s crust or upper mantle. Primary waves travel relatively slowly but they do pass through the Earth’s core (see S-wave) pyramid of biomass — a concept used in ecology that recognises that, for animals at least, there is a progressive decrease in biomass along any food chain (from lower to higher trophic levels) pyramid of energy — because of problems associated with the pyramids of numbers and the pyramids of biomass many ecologists prefer to use pyramids of energy utilised by each feeding group per square metre per annum. Pyramids of energy highlight the fact that the use of energy in any feeding stage decreases along the food chain pyramid of numbers — a concept used in ecology that recognises that, for animals at least, there is a progressive decrease in the number of species along any food chain (from lower to higher trophic levels)

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Q

quadrat — a small square frame (eg 30cm x 30cm; 1m x 1m) used to sample a small area of land for such things as vegetation, organisms,

and soils qualitative — subjective or personal judgements made quantitative — relating to the use of data such as numbers and dates quaquaversal — facing in all directions quartz — SiO2 (silicon dioxide); the most common mineral in sandstone. Although sand is a sediment of a particular diameter (ie 0.06 mm–2 mm diameter) the commonly referred to ‘sand’ is considered as the mineral quartz. Other darker minerals may form sand as on the dark sandy beaches formed from volcanic sediment Quaternary Period — a geological period in Earth history. The Quaternary Period began approximately 2 million years ago and is divided into two shorter periods – the long Pleistocene Epoch extending from 2 million years ago to approximately 10,000 years ago and the Holocene Epoch 10,000 years ago to the present (see figure 27) quaternary sector — that part of the economy involving the processing and distribution of information. Those employed in the quaternary sector are typically ‘white-collar workers’ such as

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those involved in education, government, the legal system as well as those involved in computer information processing and research. The quaternary sector is part of the larger tertiary sector. The tertiary sector involves people providing services — but services that involve physical products such as a baker delivering bread or a hairdresser cutting hair. However work involved in providing services in the form of information belong to the quaternary sector. The tertiary sector has been divided up in this way because of the enormous growth in this sector since the early 1970s (see quinary sector) quinary sector — primarily unpaid, volunteer work. Includes activities or services carried out at home on a paid and unpaid basis; including childcare and handicrafts quoquake — a term used to refer to the effect of the combined influences contributing to overall land degradation (as in ‘a quoquake’). The devastation caused by land clearing, salinity, soil erosion etc can be collectively described as a quoquake quota — the maximum or minimum level of production agreed to by a producer and the consumer of a product. For example a farmer may agree to produce a minimum yield of a crop at a set price for sale to a wholesaler


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R

rabi — the name given to the Northwest Monsoon (winter) in India and to the crops grown in this season (see kahrif) radiation fog — low lying cloud (fog) formed as a result of rapid cooling of humid areas close to the ground. During times of cold temperatures with clear skies and little or no wind, such as early mornings during late autumn-early winter, the ground loses heat very quickly. The air above it is then cooled to dewpoint where water vapour condenses to form water droplets in the air. This is seen as a low-lying fog often being about 10–100 metres deep (see condensation, precipitation) radiocarbon dating — determining the age of rocks using the rate of decay of radioactive isotopes. Carbon-14 is a rare isotope occurring in living plants and animals and is continually renewed in the atmosphere by incoming cosmic rays from space. When a living organism dies it stops taking in Carbon-14 and the carbon within the organism decays rapidly. The relationship between the Carbon14 and the decaying carbon is used by scientists, archaeologists and geomorphologists to date events in recent earth history – in particular over the last 60,000 years (see climate change, figure 12) radiolaria — freshwater and marine single-celled animals that may be soft such as amoeba or may have shells or skeletons. When these shells fall to the ocean floor they form deep ocean oozes which ultimately form chalk radiosonde — an instrument used for measure atmospheric conditions such as temperature, humidity and air

pressure in the atmosphere at high altitudes. As a balloon transports the instrument through the troposphere the information is recorded and is then transmitted to a ground receiving station rainshadow — also known as the lee or leeward slope of a hill. A rainshadow is a circumstance whereby one side of a hill is protected from rain-bearing winds that deposit their moisture on the exposed side of the hill. In the Southern Hemisphere, for example, hillslopes that face southward are exposed to the rainbearing winds from the south. The north facing slopes are much more sheltered or protected from the wet southerly winds – so the northern slopes exist within a rainshadow. The windward slopes often receive orographic rainfall while leeward slopes form a rain shadow raised beach — an emerged beach represented by beach deposits above present sea level. They are the result of the combined effect of sea level change and the rise and fall of the land. Such beaches can be tens or hundreds of metres above present sea level rampart — the raised seaward edge of a rock platform Ramsar Convention — the Ramsar Convention on Wetlands of International Importance. In 1971 an international conference was held in Ramsar, Iran, with the aim of identifying and protecting the habitats of migratory birds worldwide. There are approximately 655 Ramsar wetlands of international importance

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worldwide. Most sites are in Europe while Australia has 40 range — i) a number that can be calculated from an array of statistics to give an indication of the spread of values. For example the range of the set of numbers 23, 19, 15, 17, 63, 24 can be expressed as having a range of 40 (ie 63–23) or can be written as 23 to 63; ii) in terms of settlement and urban studies the ‘range of a good’ delineates the market area of a central place for the good – the distance people are willing to travel to purchase a good or service. The upper limit is the distance beyond which the central place no longer is able to supply that good. The range can therefore be considered as a distance eg 30 km. High order goods have a large extensive range and so large urban places tend to be spaced more widely apart rangelands — the large areas of grasslands in arid and semi-arid regions where extensive land use is practised; the predominant agricultural use is the grazing of cattle on native pasture – in areas such as southwest Queensland and northern South Australia (see arid development, extensive farming/agricultural/land use rank size — a theoretical characteristic indicating an inverse relationship between population number and the rank of an urban place. For example the population of the nth city is 1/nth the size of the largest city — ie the 7th largest city will have 1/7th the population of the largest city. Such a pattern is very unrealistic if we look at global settlement patterns today (see binary settlement pattern, primate city, figure 57) raw material — unprocessed materials, such as coal, iron ore and timber, required in the production process Rayleigh scattering — the scattering of visible light by air molecules as solar radiation enters the Earth’s

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atmosphere. Blue light is selectively scattered creating what we see as a blue sky red beds — sedimentary rocks with a very high proportion of iron oxide such as haematite. The Hamersley Ranges of Western Australia are dominated by red beds. Over 2 billion years ago the iron in the ocean waters oxidised. The subsequent iron oxide settled and formed the vast red beds which have become a major economic resource with iron ore being a major export and input of the iron and steel industry red-lining — a line drawn around poorer residential areas by financial institutions as unsuitable for investment reduced (or minimum) tillage — a technique used where soil preparation is undertaken as little as possible so as to reduce disturbance to topsoil that can lead to widespread soil erosion (see tillage) referendum — a political process by which a change is made to the constitution of a country. People vote for or against a proposed change. For a change to occur in Australia it needs to be supported by a majority of voters in a majority of states reforestation — the replanting of forests after recent clearing or as a result of tree loss through natural causes refugee — a person that leaves an area because of perceived danger or persecution. This forced migration can be the result of circumstances such as civil or regional war, natural disasters or political unrest (see emigration, immigration, migration) refugia — a habitat that has survived major climate change, such as an ice age, enabling species and population groups to survive in many cases in isolation reg — an Arabic term used to describe the flat stony desert plains of the Sahara Desert in Africa. The constant wind has blown fine sand away leaving a stony surface behind (see Gibber)


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regional shopping centre — a large free standing shopping mall of at least 46,000 m2 of leased space regolith — the thin layer of the Earth’s surface consisting of weathered and unweathered rock and bedrock. The regolith (including soil material) tends to be: • very shallow in alpine environments (because of slow chemical weathering) and shallow on the slopes of hills (because of the erosion and transport of weathered material by agents such as water and gravity) • relatively deep in more humid climates (because of the faster rate of chemical weathering) and in areas of low gradient (because water can remain in these areas to weather bedrock). Deposition in these areas by agents such as water and gravity has the effect of building up the depth of the regolith also regression — the fall in sea level on a global scale). As temperatures fell during the Pleistocene Epoch a lot of water was locked up as ice in glaciers as well as the Greenland and Antarctic ice caps. Sea levels fell 150–200 metres (exposing more land). This drop in sea level is called a regression (see transgression) regression line — this is a type of trend line drawn when one set of data is dependent upon another rejuvenation — a process whereby erosion is renewed. As rivers cut down and erode their beds, they continue this until the energy of the stream cannot erode its bed any further. However, if sea level falls or the land through which the river flows is uplifted, more energy is provided to the stream so it erodes its bed further. In this case the river has been rejuvenated. Rejuvenation can lead to features such as terraces and incised meanders relative humidity — the percentage of water that the air can hold at a

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particular temperature. For example a relative humidity reading of 75% means that the air is holding 75% of the water that it can possibly hold at this temperature. Air can hold a great deal more water vapour at warm temperatures than at cool temperatures. Therefore a relative humidity reading of 75% at 30°C, compared to a 75% reading at 20°C, means that the air is actually holding less water at 20°C – but both parcels of air are holding 75% of what they can hold relative location — the location of a point compared to some other point eg 6 km from ..., Southwest of ... (see absolute location) relict soil — a soil-type that exists today but formed under previous climatic conditions (see laterite) relief — the difference in height between two points eg 50m. Relief can also be described as being steep, gentle etc remote sensing — measurement without touching. Within physical geography it involves the use of electromagnetic radiation sensors to record images of the Earth, which can be used to yield useful information. In the 1960s remote sensing used black and white aerial photography to interpret patterns on the land. The launch of the LANDSAT 1 satellite allowed remote sensing using nonphotographic sources. Satellite imagery uses special cameras to pick up images based on the radiation given off by features on the Earth’s surface such as vegetation, soils and settlements. The patterns and relationships observed are crucial in land management and land use planning (see LANDSAT imagery, remote sensing, satellite image) renewable natural resource — a natural resource that will not run out as a result of its use; it is considered to be inexhaustible because it is in constant supply. Geothermal energy,

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wind power, wave power, tidal power and solar power are considered to be renewable natural resources reserves — that part of a natural resource base such as the various minerals (eg gold, iron ore, uranium) that has not yet been, but can be, exploited using available technology. Some resources cannot be used using available technology. However, when the technology has been developed these inaccessible resources may become reserves to be used when there is sufficient demand. For example some oil deposits in sedimentary basins around the world cannot be extracted because the technology is not available. However, future drilling techniques may be developed and these can be included in the world’s stock of oil reserves residual site — in the study of soil materials a residual site is a relatively flat area such as a plateau surface where the dominant soil-forming processes occur in situ. Epimorphism is dominant; that is weathering, leaching and new mineral formation. Typical soils include red earths and kraznozems (see depositional site, transportational site) resource depletion — the reduction in the volume, or the deterioration in the quality, of a specific resource. For example resource depletion can be seen in the deteriorating volume of oil as a result of consumption – as well as the deterioration in the quality of water for drinking and agriculture retail warehouse park — an organised development of at least three retail warehouses totalling 50,000 ft2 (4600 m2) of leased space ria — a drowned river valley. During times of lower sea level on Earth (eg 17,000 years ago) rivers cut V-shaped valleys across the shallow continental shelf. When sea level rose, these Vshaped valleys were flooded. In Australia, the flooding of the Parramatta River late formed what is now Sydney Harbour, while the flooding of the Hawksbury River

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formed Broken Bay. These are examples of ria coastlines in New South Wales ribbon development — urban development following the narrow paths of transport routes such as roads and railway lines away from the urban centre. A city for example may sprawl outwards with commercial activity following the roads while residential and industrial activity locates further behind these areas Richter scale — a measure of the intensity of an earthquake as recorded by a seismograph (see magnitude) ridge — i) a long line of high land separating two catchments or valleys; ii) in geology, the landform created as a result of magma rising to the Earth’s surface forming a long area of elevated land through which magma spreads either side forming new crust. This is exactly what is happening along the Mid-Atlantic Ridge between Africa and South America and along the East Pacific Rise in the western Pacific Ocean. Evidence of the Mid-Atlantic Ridge can be seen on the island of Iceland where the island is being split into two with active volcanoes common on the island (see figure 7); iii) an area of relatively high atmospheric pressure where the isobars extend outward from a centre of high pressure (see Trough). Air in ridges is relatively stable due to subsidence ridge and runnel topography — micro-topography that can form i) behind a beach berm whereby water flows in the deeper runnels and is separated by low ridges of sand; ii) along the sand flats exposed by receding tides riffle — a short, very shallow and fast flowing section of a stream. Riffles are commonly found along the straight sections of shallow meandering streams (see figure 25, long profile, meander, pool) rift valley — a steep-sided valley bounded by faults. In such areas the land may have sunk between these faults such as where rifting occurs. The


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Great Rift Valley in East Africa is an example. It is being split as a result of the separation of two plates. The Valley extends over 1000 kilometres north-south and hundreds of kilometres east-west (see continental drift, plate tectonics) rill — a small channel, 1mm–20 cm wide, usually developed on steep slopes of unconsolidated material such as volcanic ash and fine loose soil material. Rills develop as water flows across the surface, forming small channels, and may eventually coalesce into a larger deep, steep walled gully. rill erosion — loss of surface material such as topsoil by water eroding material in rill channels rime — also known as hoar frost, a thick coating of white ice crystals on vegetation or other surfaces (see black ice) Rio Declaration — following the June 1992 Earth Summit in Rio De Janeiro, an agreement, in principle, was developed on expected environmental outcomes of nations formalised in a document called Agenda 21 riparian land — land adjacent to a river or other body of water. The term ‘riparian rights’ refers to the rights of people whose property backs onto a river Riversleigh — an area 250 kilometres north of Mt Isa in Queensland, Australia. It is one of the world’s ric,hest fossil sites. It was declared world heritage site in 1994 because of the unique story it tells of Australia’s recent evolution as a continent. Archaeological evidence from this site indicates that this area of Australia was dominated by rainforest 15 million years ago (rather than the arid nature of the land now). Megafauna, such as the giant marsupials, Procoptodon and Diprotodon roamed eastern Australia until about 50,000 years ago when they suddenly became extinct. There is much debate as to whether a climate change or hunting by Aborigines (known as Pleistocene Overkill) led to their extinction

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river terrace — also called an abandoned floodplain. A river will cut into its bed and have a broad floodplain either side of it. If the river cuts down further, due to an increase in discharge or a drop in base level, the river will form a new floodplain leaving the old one at a higher elevation – abandoned. Identifying river terraces gives an indication of the history of river processes in the area (see figure 25) roche moutonée — an asymmetric rock typical of glacial environments (or at least providing evidence of former glacial activity). The smooth gently sloping upslope side shows evidence of glacial abrasion while the steeper downslope side shows evidence of glacial plucking or the removal of discrete pieces of rock as it becomes weakened by the overlying moving ice Rondônia — one of the States of Brazil occupying the southwest corner of the Amazonia region bordering Bolivia Rossby Wave — vast meandering waves of air in the upper level of the troposphere. A band of strong westerly winds at latitude 30°–40° North and latitude 30°–40° South do not flow directly west to east but wander north and south. In this way they play an important role in distributing heat energy across the globe (see jet stream) Rowe, Brock — one of the driving forces behind Geography in New South Wale’s secondary schools during the latter half of the 1900s. A prolific textbook writer Brock Rowe’s enthusiasm in the field, and his passion for the discipline, inspired many future geographers runoff — water flowing downhill, either across the surface as surface runoff, or beneath the surface as subsurface or groundwater runoff (see figure 32) rural — referring to the countryside such as farming or agricultural areas (see urban)

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rural urban drift — People move or drift to the city as a result of various centrifugal forces (push factors) in rural areas. These forces include famine, drought, poverty and civil war . People are also attracted to cities by centripetal forces (or pull factors). These forces include education, employment, medical services and entertainment. This rural urban drift is common in developing countries where people flood to the cities creating urban centres such as primate cities. In developed countries rural urban drift was very common in the 1950s–1980s. More recently the process of counterurbanisation has been

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significant as many urban dwellers leave the lifestyle of major metropolitan centres for a more rural lifestyle rural-urban fringe — a transition zone or area of gradual change between an urban area and a rural area. In the rural-urban fringe there tends to be a mixture of urban and rural functions such as housing estates and shopping complexes as well as market gardens and small farms. The rural-urban fringe attracts factories and other businesses because of the relatively cheap land available in the area rustbelt — a term used to refer to older decaying industrial areas of north and northeast United States (see manufacturing)

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S

Sahel — a strip of land that extends for over 5000 kilometres across North Africa. It extends from Senegal and Mali in the west through central Chad and southern Sudan to northern Ethiopia, Somalia and northern Kenya in the east. The Sahel forms the southern edge of the Sahara Desert and separates the arid Sahara Desert from the more humid Central Africa. The Sahel region marks an area of rapid change in climatic conditions. Rainfall amount changes quickly across this area and the area is subject to frequent drought and associated famine on a regular basis (see arid environment) Sahul — the continental shelf off northwestern Australia. The Sahul was exposed during the last glacial when sea level dropped creating more land. This occurred 20,000–15,000 years ago. In some areas extensive seif dunes extended across this area suggesting that the environment was much more arid than at present salina — a saline (salty) spring or marsh; a saline drainage area; also a salt bed or salt pan occurring in arid areas formed by evaporation leaving a salty crust (see playa) salinity — the concentration of salt in the soil. There are natural salts in all soils eg sodium chloride; this is called natural or primary salinity. However as a result of some activities of people additional salts are added to the soil; this is called secondary salinity of which there are two types (see dryland salinity, irrigation salinity) salvinia — a floating fern that can cover waterways in weeks and doubling in

size in 2.5 days. It is an introduced species that is degrading much of Australia’s inland waterways (see degradation) Saami — indigenous people of Scandinavia (see indigenous people, Lapp) sacred site — a place of special (eg spiritual) significance to Aboriginal people San Andreas Fault — see transform fault saprophyte — a plant that lives off decaying matter such as fallen timber and leaves. Fungi are an example of saprophytes Sargasso Sea — an area of the central North Atlantic Ocean where the mix of ocean currents combines to both elevate the sea surface about one metre above the surrounding ocean and where material floating on the surface tends to collect (see Ekman spiral) satellite image — this is an image or photograph of an area taken from space by a variety of sensors recording radiation given off by features on the Earth’s surface such as vegetation and cities. The information recorded from these sensors is then converted to an image from which decisions can be made, for example long term land use planning (see figures 62 and 66 colour, remote sensing) satellite suburb/community — a suburb or community, beyond the rural-urban fringe, that is distant from, but functionally linked to, a larger urban community. Links include the sale and purchase of goods and services as well as a labour source and source of employment savanna, savannah — a grassland with sparse trees and shrubs. The Barkly Tableland of western Queensland and

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eaastern Northern Territory is an Australian example of grasslands. (see pampas, prairie, steppe veldt) sawah — rice cultivation (farming) in Indonesia involving the use of terraces and an intricate irrigation system scalding — the process where the land is stripped bare of topsoil exposing the infertile subsoil. In this way the exposed B-horizon becomes barren and unproductive. Scalding is common where tillage has exposed topsoil to the erosive power of wind especially in agricultural areas scale — on a map this is the ratio between the distance on the map compared to the actual distance on the ground. This is shown as a line scale on the map, written in words (eg 1 centimetre represents 1 kilometre), a representative fraction (1/100,000) or a ratio (1:100,000) Scandinavia — a region in northern Europe consisting of the countries called Norway, Finland, Denmark and Sweden sclerophyll — a name given to plants with hard leathery leaves. The Eucalypt species (eg gum trees) are sclerophyll-type vegetation. Sclerophyllous vegetation is common in the temperate mid-latitude areas such as Eastern NSW, Australia. Rainforest vegetation is very different with softer and shiny leaves schistosomiasis — a water-borne disease also known as Bilharzia. Areas of poor water quality can act as breeding grounds for microscopic worms. These worms breed in particular snails in the water. The worms enter the waterway and eventually attack the liver and spleen of infected people. Infected people continue the cycle as the worms enter waterways as a result of urinating in them. The disease that results, schistosomiasis, is a very debilitating disease with people being unable to work or sustain a livelihood. Many people become blind. It afflicts more than 200 million people worldwide 144

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especially in developing countries of Africa, South Asia, Southeast Asia and Central and South America scrape — A scrape is a common geomorphic feature typical of karst topography (or at least carbonate-rich lithology). Scrapes are narrow vertical shafts extending down from the land’s surface as a result of weathering via solution — they may or may not be associated with sinkholes (see dolines). scree — loose rock debris across, or at the foot of, a slope sea — a body of salt water that is partially enclosed by land eg the Mediterranean Sea, the Tasman Sea. The Caspian Sea although totally enclosed by land is in fact a lake. sea breeze — a local breeze that blows from the sea towards the land especially in the late afternoon. During the day, the sun heats the land relatively quickly compared to the sea. As a result, the air over the land heats up forming an area of relatively low pressure. Because the sea heats up more slowly it remains cooler forming an area of relatively high pressure over it. As air of high pressure always moves to areas of low pressure a cool breeze blows from the sea onto the land; this is common in summer (see high pressure cell, land breeze, low pressure cell) sea floor spreading — the mechanism by which new sea floor is created at ridges such as the Mid-Atlantic ridge and consumed or destroyed at subduction zones. The plates either side of the ridge move apart creating new crust and therefore new sea floor. As the sea floor spreads from the ridges it plunges under less dense continental land at subduction zones. Because of this continual cycling of the sea floor the youngest sea floor is adjacent to the ridges while the oldest sea floor is near subduction zones. No where is sea floor older than 200–250 million years old, although the


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continents are older than 3.5 billion years. (see figure 17, plate tectonics, sial, sima) seamount — an isolated ‘hill’ rising more than 1000 metres above the sea floor (see guyot) SEATO — South-East Asian Treaty Organisation secession — the political act of a small territory separating from and severing ties with a larger state (or country) – eg Eritrea seceded from Ethiopia and East Timor from Indonesia secondary data — information that has already been processed or changed in some way eg information from television, textbooks and newspapers (see primary data) secondary research — research undertaken that works or manipulates information already collected by someone else. Such research relies on data already collected and collated such as in newspapers or from statistical tables rather than research that relies on original fieldwork where new information is generated (see primary research) secondary sector — that sector of the economy concerned with secondary industry (or manufacturing). Secondary industries made up over 40% of the total workforce in Australia during the 1950s. With the decline in manufacturing due to the growth in the service sector, the introduction of new technologies, and increasing competition from low labour cost overseas countries, only about 20% of Australia’s labour force is employed in the secondary sector secondary succession — see plant succession secondary treatment — following primary treatment of sewage biodegradable organic matter is removed by bacteria and other microorganisms; this stage also tends to remove potentially harmful quantities of phosphorus and nitrate (see biogeochemical cycle, phosphorus cycle, primary treatment, tertiary treatment)

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second world — a term not used widely today. In the past it referred to the relatively industrialised communist countries such as the (former) USSR and the Easter European countries. Many of these countries are now considered to be part of the developed world (see First World and Third World) sector theory (sector model) — a theory attempting to explain urban land use patterns (Figure 58). Initially proposed by H. Hoyt, the model suggests that land use patterns within urban areas can be explained by land use activity taking advantage of routes radiating for the centre of the urban area such as transport lines. The economic return received by the land use type will influence the route taken and its distance from the urban centre. In this way high income residential land use will radiate from the urban centre along the most desirable routes, lower income areas along less desirable routes and with poorer manufacturing areas occupying poorer quality land between these (see concentric zone model, multiple nuclei model) sedentary agriculture — typically applied to forms of subsistence agriculture that are practised in one place by a farmer or farmers over a long period of time, for example rice cultivation (compare this with shifting cultivation) sediment — particles derived from the weathering and erosion of rock or the breakdown of biological material. In rivers sediment is transported by water eventually to be deposited in areas where the energy of the river or the volume of water is reduced (see deposition) sediment budget — identifies and attempts to quantify present-day gains and losses of sediment to an area (or what is called a compartment). The topography of an area can be influenced by the gain, loss or balance The New Geography Dictionary

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of sediment in the area. Sediment budgets are used extensively on coastal management programs such as between headlands and between the beach and the surf zone. The movement of sediment in a coastal sediment compartment can influence areas of erosion and deposition leading to distinctive landforms such as berms, spits and offshore bars sediment load — the amount of sediment being carried by a river sediment yield — the total mass of sediment transported in a catchment area. This is expressed for example as tonnes per year or tonnes per square metre per year). The sediment in a river may be carried in suspension as suspended load, or as bedload. The sediment yield of a river reflects the topography, geology, climate, vegetation cover, as well as people’s activities within the river catchment. For example the sediment yield in sparsely vegetated and steeply sloping areas can be very high due to high rates of natural erosion. They can be even higher in areas where people have cleared land especially in erosion prone areas. Sediment yield values from catchments have been recorded of over 15,000 tonnes per square kilometre per year sedimentary basin — a topographical depression often more than thousands of square kilometres in area into which sediment has been or is being deposited. The Sydney Basin, NSW, Australia is a sedimentary basin extending from Port Stephens in the north, Lithgow to the west and Batemans Bay to the south. The sediment that has accumulated over the past 150 million years has now turned to rock extending over two kilometres in depth sedimentary rock — a rock formed from the sediment derived from the weathering and erosion of other rocks. Examples include sandstone and shale. Sediment has been deposited by water, wind, ice or gravity over millions of years, and has since turned to rock. The

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Sydney Basin, NSW, Australia is an example of an area where vast quantities of sediment have been deposited. Vast quantities of fine grained sediment were initially laid down by slow flowing meandering streams leading to what are now called the Narrabeen Shale deposits; overlying these are the coarser sands of the Hawkesbury Sandstone reflecting a faster flowing riverine environment (see sedimentary basin) seif dune — a long, linear sand dune that is aligned in the direction of the prevailing wind. Seif dunes, also called longitudinal dunes, are common in the Central Australian desert (see figure 20) seismograph — an instrument for recording earthquake shocks selva — a term used to describe the dense equatorial rainforest vegetation. The term was originally applied to the rainforest vegetation of the Amazon Basin sere — i) any stage in a plant succession eg a lithosere, a psammosere, a xerosere; ii) a plant community resulting from succession service sector — that sector of the economy concerned with the provision of services. The service sector in economies of developed countries makes up the great bulk of the workforce – such as those employed in banking, insurance, education, and government sesquioxides — iron and aluminium oxides settlement — i) a site occupied by a group of people. A village, a town, a city are settlements; ii) a process whereby people occupy an area settlement pattern — the spatial arrangement of a settlement. Settlement patterns can vary greatly as a result of factors such as landforms, climate, history, social factors and economic forces. Settlements can follow river courses at the bottom of valleys, irrigation canals or even tops of mountain ridges. The


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pattern that can result from these can be described as a linear pattern (or line pattern). In other instances such as in arid environments settlements may be separated by vast distances; this shows a sparse distribution of settlement or a dispersed settlement pattern. Where settlements group around a particular feature such as an area of rich soil or even where two rivers or major roads meet, settlement can be described as dense or clustered. Settlement patterns can be looked at on a national or continental scale by identifying the relationships between urban areas of different sizes (see primate city, rank size, binary settlement patterns) sextant — an instrument used widely in navigation to measure the angular distance between two objects. The latitude and longitude of an observer can be found by determining the apparent altitude of celestial bodies such as stars

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SEZ — see Special Economic Zone shanty town — an expression to describe dwellings recently constructed on the periphery (outskirts) of cities, especially in developing countries. Shanty towns are not slums which are close to the core of cities in developed countries. Shanty towns have emerged in cities such as Calcutta (India), Rio de Janeiro (Brazil) and Mexico City (Mexico) as a result of rapid rural urban drift due to factors such as rural poverty, civil war and drought in many rural areas (see rural-urban fringe) sharecroppers — farmers who rent their land by giving a share of their crop to the landowner sheet erosion — a type of accelerated soil erosion where a thin film of water drains across land with very little vegetation cover and removes a thin layer (eg a millimetre depth) over a wide area. This can lead to the loss of a great quantity of soil (see erosion)

Proportion of Australians Living in Urban, Rural and Remote Settlements TYPE OF SETTLEMENT

Percentage (%) of total population

URBAN big towns and cities1 (over 1 million people) other cites (80,000 - 1 million people)

59.7 12.0

RURAL large rural towns (25,000 - 80,000 people) small rural towns (10,000 - 25,000) Other2 (less than 10,000 people)

5.7 5.1 14.6

REMOTE3 Remote towns4 over 5000 people indigenous settlements5 remote, other6

1.2 0.4 1.2

TOTAL (including offshore and migrant population)

100

1. 2. 3. 4.

mainly, but not only, State capital cities such as Melbourne people from farms and from small towns in agricultural areas areas used mainly for pastoralism, mining, tourism and indigenous purposes indigenous communities whose members are residents of large country towns with a predominantly non-indigenous population 5. indigenous townships, outstations etc where people are responsible for their own municipal services 6. mostly pastoral and mining settlements with 100–5000 people, with a large Source: State of the Environment, Australia, 1995, AGPS, 1996, p.38

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Sherpa — name give to porters (or carriers of equipment) in the Himalayas (such as in Nepal) shield — an extensive area of a continent where igneous and metamorphic rocks are exposed at the surface and are dominant surface features associated with a relatively low lying topography of very old age. The Western Shield of Western Australia has rocks older than 600 million years shield volcano — a large volcano shaped like a flattened dome and built up by many flows of basaltic lava. Unlike composite volcanoes shield volcanoes cover a very wide area with slope angles of less than 10° shifting cultivation — an agricultural system characterised by field rotation in equatorial and tropical latitudes. Shifting cultivation involves: • the initial clearing of land • the burning of the resulting waste to provide nutrients for the normally infertile forest soils • the planting of a crop or crops in one field sometimes called a

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swidden • cultivating this land 2–3 years. After this time, the fertility of these soils is diminished. The shifting cultivators then move to another area and the process begins again. In this way the initial integrity of the forest is compromised with forest reduced to a very different vegetation community such as a woodland or grassland – a completely different ecosystem results. Shifting cultivation is largely a subsistence form of agriculture using relatively simple technology. Shifting cultivation is also known as swidden agriculture and slash and burn agriculture shoal — a submerged ridge, bank or bar of sand on the bed of a stream, lake or the sea. A shoal may be exposed at the surface especially at low tide shore platforms — cliffs along the coast are sometimes bordered by rock platforms extending from their base to the shore and sometimes beneath it (Figure 51 and 52 colour). It is possible to recognise a variety of these rocky shore platforms:

Figure 51 – Types of shore platforms

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• high tide platforms – almost horizontal rock platforms often with a raised rim at the seaward edge. Following continual wetting and drying as a result of tidal movements the small pools and channels produced eventually coalesce wearing the platform down to the layer of permanent saturation. High tide platforms in SE Australia reflect present day sea level • low tide platforms – horizontal or near horizontal platforms exposed briefly at low tide. These are typical of limestone rock type where solution is the major weathering process • intertidal platforms – gently sloping platforms extending from the high tide mark of the receding cliff to below the low tide mark. These platforms are common on rock types of uniform litholgy sial — the continental crust consisting of a range of minerals but mainly of silica and aluminium silcrete — a silica-rich material formed at or near the Earth’s surface. Where the products of weathering have led to silica-rich minerals, or there has been the deposition of materials by silicarich river systems over many millions of years, an indurated crust may eventually form. This crust may be between one and ten metres thick. Today in Central Australia and southern Africa this crust acts as an effective shield against erosion. Evidence of this silcrete can be seen capping the tops of mesas and buttes in arid environments (see duricrust) siliceous — relating to material such as soil being rich in silica; for example silica-rich (quartz) sand in soils showing little or no profile development silicon landscape — an area dominated by electrical and electronic equipment industry specialising in communication equipment and other electronic services.

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These silicon landscapes have been more prevalent with the growth of the computer industry. Silicon landscapes include Northeast USA; Silicon Valley, California, USA; Silicon Glen in central Scotland, and Silicon Beach in Florida, USA Silicon Valley — an area of manufacturing growth based on the microelectronics industry south of San Francisco Bay in California, USA sima — the oceanic crust and lower part of the continental crust consisting of a range of minerals but mainly silica and magnesium silt — very fine soil material typically washed away by rain and deposited by water (see loess) silviculture — the commercial growing of trees primarily for sale as commercial timber sinkhole — a hole, formed by solution, in the surface of limestone terrain often with a stream flowing into it site — the physical location of a place (eg on a hill, in a valley) skeletal soil — a shallow, infertile soil composed of a large proportion of partly weathering bedrock (see weathering) slash and burn agriculture — see shifting cultivation sketch map — a map drawn free-hand and not traced slate — a fine-grained metamorphic rock formed as a result of the application of heat and pressure on rocks such as mudstone and shale (see metamorphism) sleet — precipitation in the form of water and ice – especially a mix of water and snow slipoff slope — a comparatively gentle slope of a spur inside the bend of a meandering stream, in contrast to the steep bank on the concave, outside bend of the stream (see meander) slot valley — a valley, the cross section of which indicates that the rate of stream incision, or vertical erosion, is much greater than valley widening.

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The deep, narrow valleys have near vertical walls. Slot valleys can range in size from 100–200 cm deep where erosion follows small natural joints in the rock to valleys hundreds of metres deep as can be seen in the Blue Mountains, New South Wales, Australia smallholder — a farmer who cultivates a small agricultural area often concentrating on one or two crops smoker — a vent on the sea floor through which black, sulphur-rich gas constantly seeps. These ‘smokers’ along the major ridges of the ocean floor indicate the presence of underlying magma rising to the surface. At approximately 2–3 kilometres depth, the temperatures and pressures are enormous. Smokers are the

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fumerole equivalent on the Earth’s surface snowline — the altitude above which snow lies throughout the year and below which snow melts in summer. The snowline varies with altitude throughout the world, or even over a mountain, as a result of factors such as aspect, wind strength and direction, and slope. These factors influence both the summer maximum temperature and winter minimum temperature. For example the snowline at one site on a mountain may be 1800 metres but on another site it might be 1750 metres because of the different aspect of the slope social cost — the cost or disadvantage incurred by a community. A social cost would include the loss of open space

Figure 53 – A soil profile

The vertical scale will vary from soil to soil eg 30 cm – 1 metre

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for community use as a result of a new housing development social environment — those features that make up the human (or social) character of the area around us. The social environment includes population numbers and the distribution of people, but more importantly specific characteristics of communities such as ethnicity and interpersonal and social relationships (compare this with biophysical environment). The results of complex urban dynamics such as urban renewal and gentrification all contribute to the social environment social justice — a concept relating to the relative access to social benefits and responsibilities. Social justice is concerned with ensuring that all people have equal access to community resources such as health services, housing, water and food as well as community expectations such as employment. As such, social justice is a measure of equality of outcomes. Where people are not permitted to vote when they are legally able to, or when particular groups in a community are denied access to particular services, the level of social justice is said to be poor social capital — see social overhead capital social overhead capital — assets and resources that belong to the community rather than the private sector. Communities have developed this social overhead capital such as schools, hospitals, public transport and cultural assets through the imposition of taxes. Social overhead capital supports the ongoing functioning of communities such as cities (see infrastructure) socioeconomic group — a classification of a group based on occupation and income. A high socioeconomic group is said to have professional occupations and high incomes. A low socioeconomic group is said to have relatively unskilled occupations with low incomes

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softwood — a type of wood produced from needle-leaved trees eg pine trees SOI — see Southern Oscillation Index soil — a shallow zone of intermixed mineral and organic matter exhibiting one or more horizons that differ from the underling regolith in morphology, particle size, composition etc soil creep — the slow downslope movement of soil particles under the influence of gravity. Soil creep commonly occurs on grassed hillslopes where the stabilising effect of deep-rooted vegetation (trees) has been removed soil horizon — as it refers to soils, a horizon is a definite and recognisable layer within soil material or a soil profile. A horizon such as a B-horizon can be distinguished from other horizons in terms of colour, soil texture and fabric or a combination of these (see figure 53) soil profile — a vertical section through the soil from the surface to its parent material, in many cases showing distinctive soil horizons (Figure 53) soil texture — the character of soil as determined by the relative proportions of sand, silt and clay. A soil can be described as being ‘clayey’, or having a clay texture if it has a large proportion of clay in it; a ‘loam’ with an even proportion of sand, silt and clay, a ‘loamy clay’, a ‘sandy loam’ etc – or any combination of the three main sediment types. An interesting field technique is to form a ‘ribbon’ – try to role a moistened clump of soil (called a bolus) into a tube shape. If it forms at least a 5cm long ‘ribbon’ it has clayey texture; if it is very gritty and fails to form a ribbon the soil is said to have a sandy texture solar constant — the amount of solar radiation received on a unit area of the Earth’s outer atmosphere at the average Earth–Sun distance. The total of this energy in all wavelengths is called the solar constant which amounts to 1.94 calories per square

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metre per minute or 1.35 kilowatts per square metre solar eclipse — this occurs when the Moon passes between the Earth and the Sun. The Moon obscures the light from the Sun, received by the Earth. The Moon’s shadow is cast over the Earth. A total eclipse occurs when the Sun is completely obscured (add lunar eclipse) solar flares — these develop in sunspot regions. They can be observed as the ejection of mainly ionised hydrogen in the Sun’s atmosphere at speeds in excess of 1500 km/sec solfatara — a phase of a volcano’s life when gas and steam is released (see volcano) solifluction — the slow, downslope movement of soil material as a result of the soil being saturated with water. Solifluction is common in areas where permafrost is common. The soil is frozen in winter and upon thawing in summer the soil moves slowing downslope – especially because of the lack of tree roots in this climate to bind the soil together. Solifluction rates can range between 1–25 cm per year depending upon the angle of slope solono — a hot, dry dusty wind of the Mediterranean area solstice — the time of year when the Sun appears to be directly over the Tropic of Capricorn or the Tropic of Cancer. In the Southern Hemisphere the Summer Solstice occurs when the Sun appears to be directly over the Tropic of Capricorn on the longest day of the year, typically around 22–23 December. The Winter Solstice in the Southern Hemisphere occurs when the Sun is appears to be directly over the Tropic of Cancer in the Northern Hemisphere; this is also known as the shortest day of the year – around 22–23 June. The opposite applies when speaking of the Northern Hemisphere solum — the weathered soil above bedrock; this is usually the combined A-horizon and B-horizon

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solution — a process, whereby particles are dissolved and carried in a liquid such as water. For example salt dissolves in water and is carried in solution South Asia — that part of Asia comprising India, Sri Lanka, Bangladesh, Nepal, Bhutan and Pakistan (see Southeast Asia, East Asia, North Asia, West Asia) Southeast Asia — that part of Asia comprising Burma, Thailand, Laos, Vietnam, Cambodia, Malaysia, Singapore, Indonesia, the Philippines and East Timor southerly buster — the name given to the sudden change in weather conditions when cold strong winds follow the passage of a cold front. This is very common in southern Australia when on a hot summer’s day warm/hot northerly winds are rep laced by cold winds from the south. This change occurs especially in the afternoon and is often accompanied by short-lived heavy storms Southern Ocean — an area occupying the vast region of the Southern Hemisphere, south of Australia, between approximately 40° to 60° S latitude; 20% of all ocean area Southern Oscillation — periodic changes in atmospheric circulation over the Pacific Ocean. The ‘normal’ situation of high pressure in the eastern Pacific (towards South America with dry conditions) and lower pressure in the western Pacific and Indonesia (towards Australia with wet conditions), periodically reverses on a 2–7 year cycle leading to cycles of drought and floods (see atmosphere, figure 23, general circulation, Southern Oscillation Index, Walker circulation) Southern Oscillation Index — an indication of air pressure differences across the Pacific Ocean; in particular low pressure over Indonesia and northern Australia (read at Darwin) and high pressure over the centralwestern Pacific (read at Tahiti).


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A negative Index indicates higher than normal air pressure over Darwin indicates possible drought over northern and eastern Australia (see figure 23, high pressure cell, low pressure cell, Southern Oscillation) South Pacific Nuclear Free Zone Treaty — this treaty, or the Treaty of Rarotonga, sponsored by the Australian Government and signed by thirteen South Pacific Forum member countries is designed to prevent nuclear testing and the dumping of waste in the delimited nuclear free zone of the Pacific, and prohibit the manufacture, stockpiling, stationing and testing of nuclear weapons in Australia. The treaty came into effect in December, 1986. However, France, a non-signatory, continues its nuclear testing program at Mururoa Atoll spaceship Earth — a term used to emphasise that what happens on the Earth affects the whole planet — it is alone in space and should be considered as a single integrated entity sparse — spread out, widely distributed; a sparse population is spread out over a large area (see dense) spatial — a term to refer to an area or space; eg spatial distribution – how things are spread out over an area spatial dimension — in studying a geographic issue consideration is given as to its specific location, why it is of concern there, where else the issue may be of concern, or how it affects surrounding areas spatial distribution — the distribution or spread of features such as cities across a geographic area. The spatial distribution of features can be described as clustered or dense where features are close together, or dispersed or sparse where features are spread far apart spatial inequality — the geographic division/differences between individuals or groups. For example, spatial inequality can be seen in the location of affluent groups and those subject to

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poverty as well as the different or unequal access that these groups have to health services, employment or water Special Economic Zone — the Chinese Government has set up SEZs allowing foreign firms to establish factories in these particular areas of China (ie to allow small pockets of capitalism in China). These SEZs have been set up to: • introduce new technologies • develop links between China and overseas • attract foreign investment • employ the many young people in productive work speciation — the process by which new species evolve speleology — the study of caves speleothem — a depositional feature in caves; such as a stalactite, a stalagmite, a column, a flowstone and a curtain (Figure 54 colour). Water infiltrating through the roof of the cave is slightly acid from the decaying vegetation above. The largely calcium carbonate deposits are deposited in an array of different forms within the cave spinifex — a tough grass growing in small tufts in arid areas spit — a coastal feature where a longshore current has deposited sand forming a long depositional feature, which is linked to the land, typically exposed at the surface, and is above the highwater mark. A sand spit can extend across the mouth of a bay (extending the coastline) and in many cases closing off the bay to the open ocean forming a lagoon behind it (see longshore drift) SPOT — a French satellite, ‘Satellite Probatoire pour l’Observation de la Terre’, that provides images of the Earth’s surface. Launched in 1986 it has a resolution of 10 metres (see LANDSAT) spot height — the height in metres marked on a topographic map that has

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been measured or computed from a datum or base level such as a sea level spray irrigation — the irrigation of crops where water is sprayed from above the crop. This is very different from drip irrigation spring equinox — an event that is the result of the Earth’s revolution around the Sun. In the Southern Hemisphere this event occurs 22–23 September. At this time, the Sun appears to be directly over the equator. This is also known as the vernal equinox in the Southern Hemisphere spur — a ridge of high land sloping down to the main river channel in a catchment area usually at right angles to the river (see truncated spur) stack — a sea stack is part of a cliff that has separated from the mainland as a result of the erosive effect of waves. This is often seen as a lone outcrop of rock lying off the coast. An Australian example can be seen at The Twelve Apostles off the Victorian coast (see erosion) stalactite — an example of a speleothem. As acidic water seeps through limestone rock it dissolves various minerals. These minerals such as calcite can be seen precipitating on the ceiling of a cave and hanging from the roof stalagmite — an example of a speleothem. Forming in a similar way as a stalactite, a stalagmite forms on the cave floor as calcium carbonate in solution drips from the ceiling build upwards from the cave floor standard time — the average (or mean) time along a meridian of longitude located at the centre of a zone or country. The Earth is divided into 24 meridians of 15º. Each of these international time zones form standard time within these zones. In countries such as Russia, Australia and USA there are several standard time zones steppe — a grassland found in the midlatitude areas of Eastern Europe and Russia (see savanna)

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Stockholm Conference — a United Nations conference on the human environment, held in Stockholm, 1972 stratosphere — the region of the atmosphere approximately 15–50 kilometres above the Earth’s surface. Unlike the troposphere temperatures change every little or increase slightly with height (see figure 2) strip mining — see open cut mining Stromatolites — organic structures built up especially in marine and lacustrine environments. More than 2.5 billion years ago microorganisms trapped sediment and successively built up organic/ sedimentary layers forming these primitive colonies. The best known examples of stromatolites are on the western coast of Australia providing evidence of early life in Earth history (see figure 27) subaerial — occurring or acting on the Earth’s surface eg subaerial weathering occurs on the surface of the land, opposed to the marine weathing subduction zone — a zone where one lithospheric plate dips beneath another forming an ocean trench. As one plate moves towards another the ocean floor plunges underneath the continental crust because the former is more dense (or ‘heavier’). The ocean floor slides under the land at a very steep angle. This subduction zone can extend as deep as 700–1000 km. These are the sites of major earthquakes and at these depths rocks become molten and eventually rise to the surface to be seen as volcanoes. Subduction zones are what are called convergent plate boundaries because these are the sites where plates collide. Evidence of these can be seen around the Pacific Ring of Fire (see figure 17) sublimation — the change of a substance from one state to another but bypassing an intermediate state. For example the change of state of ice (solid state) directly to a gas without the intermediate liquid phase.


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Sublimation is common in very high latitudes such as in northern Scandinavia and northern Canada sublittoral zone – below low tide level (see littoral zone, supralittoral zone, tides) subsidence inversion — an inversion in the upper troposphere. In the lower atmosphere when air rises it cools adiabatically due to the air expanding in an area of lower pressure. The air temperature near one kilometre, for example, might be 2°C. However air tends to sink (or subside) in subtropical high pressure systems such as over central Australia. As the air sinks from high altitudes (eg from over 5 kilometres altitude) it warms up as a result of compression. The temperature of this subsiding air at, for example, one kilometre might be 3°C. The lower air near one kilometre is cooler (2°C) than the air just above it (3°C). The lower cooler air cannot rise any further. There generally is no cloud in the subsiding air. The implication of this is that air in the lower atmosphere finds it difficult to rise to such altitudes to produce rainfall. A subsidence inversion like this is common over arid areas in the subtropics (20°–30° latitide north and south of the equator) (see adiabatic lapse rate, subtropical high pressure cell) subsidiary — a branch of a larger corporation which tends to specialise in a particular aspect of the larger corporation or operates in a different market — either domestic or overseas subsistence — a term used to describe the objective of a type of agriculture where food is produced for personal (or domestic) consumption rather than commercial production where food is produced for sale subsistence agriculture — an agricultural system in which little or no surplus is produced. The crops grown or cattle raised are primarily for the

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individual’s consumption and not for sale. subsistence economy — an economic system whereby people produce the bulk of their own food for consumption. Production and consumption are restricted mainly to the family unit with very little exchange between groups. Although traditional rice cultivation and shifting cultivation have been described as examples of subsistence agriculture, there are virtually no subsistence economies in world today as a result of the social, political and economic contacts between all areas of the Earth subtropical high pressure cell — a feature of relatively high air pressure within the global atmospheric circulation. These areas of high pressure are located between the tropical latitudes of 20°–30° north and south of the equator. Between these latitudes air is descending through the troposphere forming an area of high pressure. This leads to dry surface conditions as can be seen in areas such as central Australia and the Sahara Desert in North Africa. The main reason for this is that as the air sinks it warms adiabatically at 10°C per kilometre (see adiabatic lapse rate, general circulation, figure 26, subsidence inversion) suburbanisation — a process whereby work, services, population and housing estates are located in dispersed areas beyond, and independent of, the city core succession — see plant succession succulent — a type of plant with juicy/fleshy leaves (eg cactus) Sudd (the) — an area of southern Sudan (Africa) through which the White Nile flows. The area is dominated by low-lying swamps and being subject to inundation during heavy rains summer solstice — an event that is the result of the Earth’s revolution around the Sun. In the Southern Hemisphere this event occurs 21–22 December.

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At this time the Sun appears to be directly overhead at 23½°S (Tropic of Capricorn); this is known as the longest day of the year in the Southern Hemisphere. In the area south of the Antarctic Circle (66½°S) light is received 24 hours of the day sunbelt — a term used to describe the prosperous and growing areas of the south and west of the United States Sunda Land — that part of the continental shelf between Australia and Southeast Asia including Java, Sumatra and Kalimantan. It was the Sunda which early Aboriginal people crossed from Asia into Australia approximately 100,000 years ago. They did not only walk across when sea level was lower but used water craft at times to ‘island hop’ the much shorter distances that were available to them (at 105,000, 55,000 and 17,000 years ago) sunrise industry — new and existing industry taking advantage of new technology such as computer technology and new methods of

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production – especially used when referring to new service industries sunset industry — old and declining industry often producing old and out dated products using out of date technology and methods of production – especially used when referring to manufacturing industry sunspots — regions on the Sun’s surface of intense magnetic disturbance (100–1000 times the average for the Sun). They appear dark because convection on the Sun’s surface is reduced leading to cooling by the emission of radiation seen as solar flares supralittoral zone — above high tide level (see littoral zone, sublittoral zone, tides) sustainable development — a concept that suggests that economic development can proceed indefinitely as long as the rate of use of natural resources does not exceed the rate of replacement of that resource nor does it adversely affect the quality of other aspects of the natural or human environments

Figure 55 – An example of a synoptic chart

SCALE: 1

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CM

= 900

KM


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sustainable yield — an objective of resource use in which the rate of use does not exceed the rate of replenishment or renewal. For example, in the fishing industry a sustainable yield is one in which fish catches do not exhaust the stock available — ie fish stocks are continually replaced allowing for the long-term use of this resource. The same applies to resources such as forests, and fossil fuels (see sustainable development) swale — a depression between two sand dunes. In coastal environments the swale between two frontal (or parallel) dunes is often thickly vegetated, for example by taller trees, due to the more protected and moist microclimate swallow-hole — where a surface stream disappears underground especially in limestone terrain (see doline, karst, sinkhole) S-wave — a seismic wave within the Earth (generated by an earthquake) due to movement in the Earth’s crust and upper mantle. Secondary waves do not pass through the Earth’s molten core. As a result they are not received on the opposite side of the globe. There is a ‘shadow’ or area where these waves are not recorded (see Pwaves)

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swash — as a wave breaks along the coast the water rushes up the beach face; this water is known as the swash (see backwash, longshore drift) swell — the movement of water consisting of wind generated waves that were formed in another area. The long wavelength of these waves is reduced as these waves approach the coastline. Swell can be seen as those waves moving onshore from far out to sea (see figure 14) swidden — see shifting cultivation swidden agriculture — see shifting cultivation syncline — the trough in a fold formed as result of Earth movement (see fold mountains) synergism — the process by which the combined effects of two or more substances are greater than the sum of the individual effects synoptic chart — also known as a weather map which gives a summary of weather being experienced in an area (eg over Australia) by the use of isobars. We can then determine wind directions and estimate temperatures etc (see figure 55) syzygy — one of two points where the Earth and the Sun are aligned with the Moon or another planet

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new geography dictionary geography dictionary new dictionary new geography

T

taiga — an area of coniferous forest near the Arctic Circle. The cold winters in areas such as the countries of Scandinavia (Russia and Canada allow only a short growing season with trees such as spruce and pine adapted to this condition tailings dam— a dam that collects the waste material from mining sites and processing sites where the material collected is deemed too poor to be processed further. For example tailings dams are used to collect waste from gold and uranium mines Talgai — the name given to the first Australian Pleistocene human skull – found in southern Queensland Australia in 1886 with a minimum age of 14,000–16,000 years (see Kow Swamp, Lake Mungo) talus slope — a slope at the foot of a cliff made up of weathered rock debris (see scree, weathering) taluvium — as a jointed rock mass breaks down on a hillslope the mixture of this talus from the breakdown of joint blocks, and colluvium is collectively known as taluvium (see weathering) tariff — a tax on goods entering a country making the product more expensive tarn — a glacial lake. A cirque has scoured into the side of a mountain by the action of ice. Upon melting, the depression has filled with water forming a lake or tarn (see figure 28) TCM — see total catchment management technoburb — a node that is functionally separated from the city proper, made possible by technologically advanced industries 158

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tectonic — a term that relates to processes that operate within the Earth. The various types of mountain building and folding and faulting are tectonic processes (see fault, fold, fold mountains, volcano) teleworking — or telecommunicating, where electronic communication enables people to work from home rather than physically travel to a workplace temperate — a name given to describe those areas and climates of the Earth that are not subjected to continual extremes of temperature and precipitation. Temperate areas (or latitudes) include Australia’s southeastern coast of NSW, the east and west coast of the USA and South Africa. Temperate areas contrast with tropical and equatorial climates, the arid climates of many west coast and central areas of continents, as well as the subpolar and polar climates of higher latitudes temperature range — the difference between the highest and lowest temperatures (eg 30°C–20°C has a temperature range of 10°C) tenement — a large multistorey city building that is divided into rooms or apartments for rent. Tenemants provide high density, often poorquality, accommodation tenure — land ownership (see freehold tenure, land tenure, leasehold land) tephra — material ejected from a volcano during an eruption including ash, dust and large rocks or boulders called volcanic bombs (see volcanic rock) tephrochronology — a dating technique using tephra from a volcanic eruption. The date of the tephra is determined so that material above and below the tephra can be correlated to


ary ew hy

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give relative age. Material below the tephra is older than the date of the tephra and in turn younger than a lower tephra layer. Compare with dendochronology (see volcano) Terania Creek — the site of the first anti-logging demonstration in Australia (1979) — 30 km north of Lismore, NSW Australia terminal moraine — glacial sediment accumulated at the toe or lower part of the glacier ternary graph — a triangular diagram measuring three related variables rather than the more familiar two; for example, comparing the relative proportion of people working in the primary, secondary or service sectors of the economy. Each side to the graph, an isosceles triangle, has a scale. The scale is read by reading the numbers on the scale 0–100 from the lower right corner at 60° to the axis that is being read Terra Australis Incognita — Latin meaning ‘unknown southern land’; used when referring to Australia especially in the seventeenth century during early exploration terrace — see river terrace terrestrial — a term relating to the Earth, or of living on the land. For example, terrestrial vegetation is vegetation growing on the land rather than in the ocean (see aquatic) territorial waters — waters under the jurisdiction of a country including seas and inland water bodies Tertiary Period — a period of geological time 66.4–2.8 million years ago. Part of the Cenozoic Era (see figure 27) tertiary sector — that sector of the economy concerned with the provision of services. In most developed countries, the tertiary sector makes up over 75% of all types of employment. Those people employed in the tourist, insurance, and computer service industries belong to the tertiary sector (see primary sector, quaternary sector,

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quinary sector, secondary sector, service sector) tertiary treatment — the removal of a range of substances such as nitrates, phosphates, chlorinated compounds, toxic organic materials, heavy metals, acids, and salts. Bacteria and even smaller viruses can be removed with microfiltration technology (see primary treatment, secondary treatment) Tethys Sea — the body of water that separated the northern landmass of Laurasia from the southern landmass of Gondwana texture — see soil texture texture contrast soil — a soil with a marked contrast (or difference) between the upper A-horizon and the lower B-horizon. In situ processes, such as weathering, acting on the bedrock, produce a relatively fine textured clayey B-horizon. Surface processes, such as slope wash and soil creep acting across the slope and over the B-horizon, produce a much more coarse sandy-loam Ahorizon. Some examples of texture contrast soils are the red and yellow podsols. These soils are commonly found on hill slopes (see duplex soils) thalweg — a theoretical line along the course of a river joining the deepest parts of its bed (see graded profile, long profile) thematic map — a type of map that shows a particular topic or theme such as how temperature, population or incomes vary over an area The North — a term used to describe the more developed countries of the world. The North includes Canada, USA, Australia, New Zealand, Japan and countries of Europe (see Brandt line) the Sudd — see Sudd (the) thermocline — the surface layers of the oceans are a mixture of warm temperatures, mixing waves and variable currents. Below this, about 100m below the surface, the The New Geography Dictionary

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temperature falls very rapidly for about 1000 metres. This is called the thermocline. Below the thermocline, 1–3 kilometres deep, temperatures are just above freezing point and temperatures decrease very slowly with depth thermal expansion — a type of physical weathering whereby the heat received by a body, such as a rock, leads to the expansion of the outer layers of that rock. This in turn can lead to the outer layers of the rock peeling off (see exfoliation) thermosphere — a region in the atmosphere, greater than 80 km altitude, where temperature increases rapidly with height. The temperature can reach over 1000ºC due to the increasing absorption by atomic oxygen and ozone of incoming shortwave radiation from the Sun (see figure 2) The South — a term used to refer to developing countries of the world. The South includes countries such as India, Libya, Thailand, Costa Rica, Brazil and Argentina (see Brandt line, The North) third world — a term not used widely today. In the past it referred to the poorer countries experiencing great poverty in Asia, Africa and Central and South America. These are now referred to as developing countries, The South or the majority world (see first world and second world) three mine policy — a policy called the Three Mine Producers Policy of the Hawke Labor Australian Government (1983) approved Nabarlek and Ranger mines (Northern Territory) and Olympic Dam (South Australia). Nabarlek is no longer operating; it was decommissioned in 1995. Olympic Dam produces 2 billion tonnes of ore consisting of 30 million tonnes of copper and over 100 million tonnes of uranium. It is an underground mine unlike the open cut mine of Ranger. Ranger Uranium Mine, 260 km east of Darwin, is owned by ERA (Energy Resources Australia), covers an area of

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79 square kilometres and is surrounded by Kakadu National Park threshold population — the minimum population number required to support the provision of a good or service by a central place (see central place theory) throughflow — the downslope flow of subsurface water through the voids (or spaces) in the regolith towards a channel or the water table (see figure 32) Thylacoleo carnifex — part of the extinct megafauna that roamed eastern Australia prior to 15,000 years ago; a ‘marsupial lion’ thought to be a carnivore tidal bore — the ‘pulse’ of water sometimes seen as water moves upstream as a result of the incoming tides tidal power — power or energy produced as a result of the rise and fall of the tides. A barrage across an arm of the sea, as in an estuary, rises and fall with the tide. As the tide rises and falls it turns hydraulic turbines as water passes through them. This is an example of renewable energy with little impact on the environment. However costs are prohibitive (see renewable natural resource) tides — these are the regular movement in ocean levels as a result of the gravitational attraction between the Earth, the Moon, and to a lesser extent, the Sun. The gravitational force exerted by the Moon on the oceans facing the Moon causes the oceans to bulge out slightly — this causes high tides. In some areas tides can rise over 10 metres. When the Earth, Moon and Sun are in alignment they cause a maximum rise and fall of the oceans that called spring tides. When the three bodies are at right angles to each other the forces are minimal and very small tides result called neap tides. The effects of tides can be seen upstream in rivers as a tidal bore moves up river and a small wave can sometimes be seen moving upstream. Contrast with a tsunami tied aid — see foreign aid


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Tierra del Fuego — the southern region of Argentina and the South American continent. It is actually an island separated from the mainland by the Strait of Magellan. The western half of the island is part of Chile till — a mixture of rocks and clay typically deposited over the landscape by glaciers such as over central and northern North America and Europe during the last glacial period. Till deposits indicate the previous presence of glaciers and evidence of climate change in the area in which till is found (see deposition) tillage — the preparation of topsoil for crops or for weed control by machinery TNC — see transnational corporation tombolo — a spit that links an offshore island to the mainland as a result of longshore drift. In the example of Palm Beach (Figure 56) recent research suggests that this may not be a tombolo at all. Underlying bedrock suggests that a now submerged ridge extended to Barrenjoey making Palm Beach a bayhead beach Figure 56

N

! SCALE: 1

CM

= 500

M

The tombolo of Palm Beach, NSW, Australia, linking the ‘island’ of Barrenjoey to the mainland

topographic map — a large-scale map of part of the Earth’s surface illustrating various features of the

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biophysical environment, such as hills, valleys and vegetation, and the built environment that includes buildings and roads (see figures 64 and 68 colour) topography — the shape and physical features of the Earth’s surface including hills, valleys, mountainous and gently-sloping topography topology (and topological map) — this is concerned with the order and relative position of the feature rather than their actual positions or dimensions. A railway map is a typical example of a topological map in that it shows where railway stations are in their correct order but not necessarily the actual distances between these stations tornado — an intense area of low pressure originating over land. The violent storm can be seen around a long funnel cloud impacting on a relatively narrow area compared to the broad areas of devastation associated with tropical cyclones. Tornadoes are thought to originate when a layer of dense cold air moves over a layer of warm, moist unstable air. Because of this difference, energy is released. The sudden displacement of air causes an intense area of low pressure sucking air in from the sides then rising rapidly. The spin of the Earth causes the air to spiral upwards (see low pressure cell) total catchment management — the integrated management of all land use types within a catchment area. Landowners, residents, government departments and private organisations have an interest in their catchment. These groups and individuals make land use decisions with the objective of having little or no negative impact on the quality of resources within that catchment. In this way, the whole catchment is protected from various forms of land degradation and the long-term sustainable development of the catchment’s natural resources is assured tourism — the temporary and free movement of people to destinations

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outside their normal residence and workplace in order to experience contrasting lifestyles and/or environments trade liberalisation — a trading policy based on free market conditions with little or no government influence such as tariffs trade waste — waste from industrial processing. Trade waste includes liquids such as oils and fats, solids such as paper and metals and gases emitted from chimneystacks. Trade waste is particularly an environmental problem in densely populated areas and especially in rivers. Many rivers become aquatic deserts as life forms die through lack of oxygen. This occurs because oxygen is used up to break down the many forms of trade waste trade winds — easterly winds that blow from the subtropical latitudes (such as latitude 20°S–30°S) towards the equator. In the Southern Hemisphere they are called the Southeast Tradewinds because the coriolis force deflects these winds to the left. In the Northern Hemisphere winds blowing from the subtropics to the equator are called the Northeast Tradewinds (see figure 26, general circulation) tragedy of the commons — where a publicly owned, freely available, unregulated resource is likely to be overexploited. First used in relation to the progressive degradation of ‘the commons’ in England. The tragedy of the commons idea is used to argue for government control, good management of modern ‘commons’, and the promotion of ecological sustainability so that those who accrue profits meet all environmental needs (see sustainable development) transect — a cross section of part of the Earth’s surface. A transect diagram gives a summary of features along this transect including settlement and landforms (see topographic map) transfer pricing — a term used to describe price-setting for different products within the one company

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transform fault — a fault in the Earth’s crust the result of two crustal plates sliding past one another, rather than one plate being subducted beneath another, or the two plates colliding and then forming features such as fold mountains). The San Andreas Fault (USA) is an example of a transform fault as the North American Plate slides passed the Pacific Plate (see figure 44, subduction zone) transgression — a rise in sea level on a global scale . The coldest phase of the last glacial period, 20,000–17,000 year ago, saw sea levels at 150–200 metres below present with water locked up in glaciers as well as the Greenland and Antarctic ice caps. As climates warmed the glaciers and ice caps began to melt. Sea level rose to reach its present level by approximately 6000 years ago. This transgression of the ocean saw the flooding of fiords and rias (see climate change, regression) transgressive dune — a dune common in coastal dune systems, formed as a result of onshore winds blowing large volumes of sand inland. These dunes indicate that the main foredune has been destabilised in some way such as vegetation being removed by walking tracks. They are also known as blowouts transhumance — the seasonal movement of people or cattle up or down mountain sides or on the desert fringe in search of better pastures. An example of this is the downslope movement in winter to warmer temperatures and a more plentiful food source transmigration — a resettlement program undertaken by the Indonesian Government that has seen movement of people from the densely populated island of Java to less densely populated areas such as, Kalimantan and Irian Jaya and the islands of Sulawesi and Lombok


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transnational corporation — a large company that operates in more than one country. In many instances TNCs control various aspects of the production process. Examples include General Motors, Exxon, General Electric, Samsung, Unilever and British Petroleum transportational site — in the study of soil materials transportational sites are areas such as hillslopes, where soil materials are the result of two main processes. The upper A-horizon is the result of surface processes such as slope wash and soil creep leading to a relatively sandy texture with little or no pedal development. The lower B-horizon has a much more clayey texture, the result of in situ process such as weathering leaching and new mineral formation. Texture contrast soils are typically found at transportational sites (see depositional site, duplex soils, podsols, residual site) travertine — a form of limestone that forms features such as stalactites and stalagmites created by the drips of calcium-rich springs Treaty of Rarotonga — see South Pacific Nuclear Free Zone Treaty tree — a woody plant usually with one stem and more than 5 metres tall tree line — the altitude, above which, trees do not grow. Although temperature is a major factor, the position of the tree line is influenced by a range of other factors such as aspect, slope, soils and drainage. The position of the tree line on one side of a mountain may be 1750 m whereas it might be 1810 m on another side because of differences in temperature, moisture and soil type (see snowline) tree preservation order — a power exercised by a local planning authority NSW such as the local council, that prohibits the lopping, clearing or deliberate destruction of local trees or groups of trees

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trend line — a line drawn on a scattergraph to emphasise the main pattern (or trend) in the data shown. Two types of lines are a line of best fit and a regression line tributary — a small stream that joins another to form a larger river (see figure 25) trophic level — a level in a food chain. A trophic level can be represented by a pyramid where the base is tropic level 1: producers, level 2: herbivores, level 3: carnivores, and level 4: omnivores (see pyramid of biomass, pyramid of energy, pyramid of numbers) trophic structure — feeding relationships within and between ecosystems tropical cyclone — an area of intense low pressure common in northern Australia and Indonesia bringing strong winds and torrential rainfall (see hurricane, low pressure cell, typhoon) Tropic of Cancer — an imaginary line around the Earth in the Northern Hemisphere (23½°N) Tropic of Capricorn — an imaginary line around the Earth in the Southern Hemisphere (23½°S) tropopause — the boundary between the troposphere and the overlying stratosphere. The altitude of the tropopause varies from about 15 km at the equator to about 6–7 km at the poles (due to greater convection at the equator ). Within the tropopause, temperatures tend to increase with height or remain constant, unlike the troposphere. Because of this physical characteristic there is little transfer of air across this layer. The tropopause acts as a lid, or inversion, above the troposphere. Rising convection currents such as within thunderstorms cannot easily break through the tropopause. As a result the area is characterised by relatively clear skies free of cloud (see figure 2, adiabatic lapse rate, troposphere) troposphere — the area of the Earth’s atmosphere in which our weather The New Geography Dictionary

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occurs (coming from the Greek meaning ‘turning’). Within the troposphere insolation enters the Earth’s atmosphere and is absorbed by the land and the oceans. This short wave radiation is converted to long wave radiation (or heat). This heat energy then heats the atmosphere by processes such as conduction and convection. Convection is much stronger in the low equatorial latitudes so the troposphere is much deeper here (approximately 12 kilometres) whereas the depth decreases towards the poles (approximately 5–8 kilometres) because the air is more dense. Within the troposphere, temperature tends to decrease with height at about 6.5°C per kilometre. This ‘normal, or environmental lapse rate can vary greatly (see figure 2) trough — an area of relatively low air pressure where the isobars extend outward from a centre of low pressure. Air in troughs is relatively unstable with air rising from the surface and diverging at higher altitudes. Troughs are often associated with fronts and can lead to cooler and sometimes stormy weather (see ridge) truck farming — the production of fresh vegetables at a great distance from the market to which they are to be sold. Fast and refrigerated transport has allowed this type of farming on the periphery of metropolitan areas (see commercial farming) Truganini — the last surviving Aboriginal (female) in Tasmania (Oyster Cove, south of Hobart). Truganini died in 1876 aged 71. The last surviving male was William Lanney (King Billy) who died in 1869 aged 34 truncated spur — the lower end of a spur that has been ‘cut off ’ (or truncated) by erosive action. This may be caused by a glacier (see figure 28, erosion)

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tsunami — a sea wave, with a large wave height up to 15 metres, often resulting from an undersea earthquake. Tsunamis are often mistakenly called ‘tidal waves’; they have nothing to do with the diurnal tides tuff — fine-grained material, such as ash, ejected from a volcano commonly found as a sedimentary deposit at the base of the volcano. Evidence of tuff is used to indicate that volcanic activity occurred in a particular area, and as a source of dating archaeological events (see climate change, sedimentary rock, tephro-chronology) tundra — vast, relatively flat treeless and often, marshy plains characterised by the presence of permafrost. Tundra has normally been associated with the vast northern areas of Canada and what is now Russia. Plants such as mosses, grasses and low heath plants are common and adapted to the cold temperatures and seasonally frozen and wet land surface. The term tundra is used more widely to also include those lands above the tree line in alpine environments turbidity — a measure of the ‘murkiness’ of water. Turbidity is caused by suspended solids in the water such as soil material having been washed into a river following heavy rainfall. Water with a high turbidity is detrimental to much aquatic life because the suspended material tends to block sunlight from penetrating to any great depth and so limiting the process of photosynthesis Twelve Apostles — located off the southwest coast of Victoria, Australia these sandstone rock stacks (see stack) form part of the rugged coastline weathered and eroded over millions of years (see erosion, weathering) typhoon — an area of intense low pressure common in Asia bringing strong winds and torrential rainfall (see hurricane, low pressure cell, tropical cyclone)

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U

ubac — the side of a hill most sheltered from the sun UN — (see United Nations) underclass — the poor forced to the margins or out of the labour market in a postindustrial society, thus excluded from the mainstream life of society underemployed — a phenomenon whereby people are in employment but do not have sufficient work to occupy them underfit stream — see misfit stream UNDP — United Nations Development Program. Created in 1965 the UNDP has four priority areas: • the elimination of poverty • creation of jobs and sustainable livelihoods • advancement of women • the protection and regeneration of the environment. Much of the work of the UNDP is directed to restoring societies after war and humanitarian emergencies. The majority of funds is directed to developing countries with over 80% aimed at countries with GDP per capita of less than $750 undulating — refers to gently rolling land (or topography) rather than flat or even steep land UNEP — United Nations Environment Program. This was established in 1972. The UNEP has the task of developing and promoting sound environmental activities around the world. With the increasing consumption of natural resources around the world, such as forests, fossil fuels and marine stocks, the UNEP is focusing on sustainable development practices to enhance environmental quality and the quality of life of people

UNESCO — United Nations Educational, Scientific and Cultural Organisation uniform texture — in describing soil texture, a uniform texture has a similar texture grade throughout the solum (see duplex soil, gradational texture) uniformitarianism — a concept that directed much thinking in the 19th and early to mid 20th centuries. It suggested that the processes that act on the Earth today are of the same type, and operates at the same rate, as those of thousands and millions of years ago. This idea of uniform processes and rates, suggested by the phrase ‘the present is the key to the past’, has been largely discredited. The catastrophic processes associated with the atmosphere, hydrosphere, lithosphere and biosphere, such as rise and fall of sea levels, tsunamis, earthquakes and mass extinctions, have given rise to the concept of catastrophism where the past can be seen as the key to the present United Nations — an organisation of governments from around the world. It attempts to promote political, social and economic stability around the world. Its work is seen in the media as attempting to promote peace between conflicting nations. The UN was established in 1945 by 51 countries untied aid — see foreign aid upper catchment — the area of a river catchment area where the river and its tributaries begin their journey to the sea urban — a term relating to a large permanent settlement/built-up area with a relatively dense population compared to its hinterland. The New Geography Dictionary

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Major Urban Agglomerations Urban Area

Country

Population

Tokyo

Japan

27,242,000

Mexico City

Mexico

16,908,000

Sao Paulo

Brazil

16,792,000

New York

USA

16,390,000

Bombay

India

15,725,000

Shanghai

China

13,659,000

Los Angeles

USA

12,567,000

Calcutta

India

12,118,000

Buenos Aires

Brazil

11,931,000

Seoul

Republic of Korea

11,768,000

Source: United Nations Population Division, 2000

Urban areas concentrate on the provision of urban rather than rural services. Urban services include tourist information, computer services, and corporate headquarters rathern than servicing farms. Examples of urban areas or urban settlements include Sydney, London, Mexico City, Alice Springs and Ballarat). Major urban areas have a great concentration of people and

economic activity. These are known as urban agglomerations. urban blight (see urban decay) urban consolidation â&#x20AC;&#x201D; a process whereby closer settlement occurs and is encouraged. An example of this is the case where single dwellings on relatively large blocks of land being replaced by two or three houses, or even multiple townhouses. In both cases, the new houses take advantage of existing

Figure 57 â&#x20AC;&#x201C; Examples of urban hierarchies

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infrastructure such as water and power supplies urban decay — (also known as urban blight); the decline in the quality of an urban area such as the physical decay of buildings and roads. Also included is the economic decline of an area where businesses close down or move elsewhere, subsequent decline in employment and income occurs, and social breakdown includes crime such as vandalism urban hierarchy — the network of, and relationships between, urban places reflecting population size and functional diversity (Figure 57). There are a number of models of urban hierarchies including the central place theory and rank size rule (see Primate City) The global urban hierarchy of today has seen the emergence of so-called global cities such as New York, London and Tokyo. Their political, economic and technological power reaches all areas of the globe, whereas smaller centres such as Melbourne and São Paulo have much smaller hinterlands, (or spheres

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of influence) with fewer and less significant interactions within the global urban hierarchy (see Christaller, W., rank size) urbanisation — i) the increasing concentration of urban activities in an area; ii) the increasing percentage or proportion of people living in urban areas of a country. The term level of urbanisation is often used. For example the level of urbanisation might be expressed as 82%. This means that of all the people in an area, such as a country, 82% live in urban areas and only 18% live in rural areas urban models — (see concentric zone model, multiple nuclei model, sector theory, Figure 58) urban renewal — the upgrading of urban areas (eg inner city areas) by either demolition and replacement of existing buildings (development) and/or improving existing structures (renovation) urban sprawl — the outward growth of the city, where residential/commercial/industrial land use activity replaces previously rural land

Figure 58 – Urban models

2

8

4 3

1

1 3

1

2

5

4

2

5

3 4 5

Concentric zone model 1. 3. 5. 7. 9.

7 Sector model

CBD residential, low income residential, high income outlying business complex industrial suburb

2. 4. 6. 8. 10.

6

Muliple Nuleii model

wholesale/light manufacturing residential, middle income heavy manufacturing residential suburb commuter zone

Source: W Andrews & J Fien eds, The urban environment, Prentice-Hall of Australia 1981, page 115

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U-shaped valley â&#x20AC;&#x201D; when a glacier carves out a valley, as it slowly moves downslope, the valley forms the shape of a U. When these types of valleys are

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filled with water from the ocean following the melting of the glacier a fiord is formed (see figure 28, Vshaped valley, )

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V

vapour pressure — a measure of the internal pressure exerted by a water droplet. When the vapour pressure of the water droplets in a body of water exceeds that of the overlying atmosphere, evaporation occurs. At low temperatures, vapour pressure increases only slightly as temperature increases slightly but at high temperatures vapour pressure increases greatly with only slight temperature increases. The significance of this is that small temperature increases in tropical environments will lead to much greater rainfall than small temperature increases in areas of higher latitudes or altitudes (see atmosphere) varve — an alternating sequence of a thin layer of fine sediment and course sediment within a sedimentary sequence. This is typically found in the meltwater of glaciers. The fine sediment settles out indicating very slow flow especially during winter or prolonged cold periods. This occurs because most water is locked up as ice. During the warmer summer, the flow of this meltwater is much greater and so can carry larger and heavier sediment. This is because there is much more meltwater in the warmer season. Sediment will eventually be deposited. There is then a sequence of fine and coarse sediment indicating seasonal temperature rhythms. The sequence of varves can be used to determine what the environment or climate was like when these varves were deposited (see figure 12, climate change) V-shaped valley — when rivers erode the valley in which they are located they tend to erode vertically

downward carving a V-shape into the land (see erosion , U-shaped valley) vegetation — the plant cover of an area. Vegetation can be considered as individual species (eg Eucalypts) or as an interacting community of a variety of species (eg a rainforest) veldt — extensive treeless grassland in southern Africa ventifact — a rock or stone that shows evidence of sand blasting or abrasion on its flat surfaces. It also shows sharp ridges between the furrows created by the abrasion. Ventifacts are common in arid environments where wind transports sand at high velocities (see weathering) verga — an atmospheric phenomenon whereby precipitation (raindrops or ice) evaporates as it falls through the atmosphere forming what appears to be a ghostly cloud high up in the atmosphere (see evaporation, weathering) vertical exaggeration — a measure of how much the vertical axis of a cross section has been stretched or exaggerated in order to see the shape of the land. Vertical exaggeration is calculated as: Vertical Scale (VS)

VS HS

Horizontal Scale (HS) That is: (of the cross section) eg 1 cm rep. 100m (of the map from which the cross section has been drawn) eg 1 cm rep 1000m 1 100 1 1000 = 10

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vertical integration — a form of business expansion where a business expands forwards or backwards in the production process. For example, a steel manufacturer may expand backwards by acquiring an iron ore lease or coal mine (its raw materials); it may expand forwards by establishing a business to sell or even market its product vertical relief — along a transect vertical relief is a measure of the extremes in height between any two points — the highest point minus the lowest point along a transect including the two points on the transect village — a nucleated rural settlement that has a range of functions, such as a church and local store, that are in frequent demand (see central place, hamlet) viscosity — the tendency of a substance to resist flow. An increase in viscosity implies a decrease in flow; for example a fast moving lava flow is said to have

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low viscosity; a slow flowing lava is said to be very viscous or to have high viscosity viticulture — a type of agriculture where grapes are grown eventually for wine production volcano — an opening in the Earth’s crust that has allowed magma to reach the surface (see composite volcano, extrusion, shield volcano) volcanic neck — the solidified magma within the vent or neck of a volcano. Weathering and erosion often strips soil and debris from around the neck of the volcano exposing a tall, steep sided structure. The volcanic terrain of The Warrumbungle Mountains, NSW and The Glasshouse Mountains, Qld Australia has many volcanic necks volcanic rock — rock formed from volcanic action such as the solidification of lava forming basalt rock; another example is obsidian (a volcanic glass).

Figure 59 – The von Thuenen land use model

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Volcanic rock is a type of igneous rock that has cooled quickly on the Earthâ&#x20AC;&#x2122;s surface. As a result, the crystals that make up the rock are very small. Other types of igneous rock that have cooled more slowly have much larger crystals (see extrusion, volcano) von Thuenen model â&#x20AC;&#x201D; a model of agricultural location theory developed by J.H. von Thuenen (Figure 59). Assuming a single market, surrounded by an isotropic surface, such as farmland being uniformly flat and of uniform fertility, and with transport costs increasing uniformly in all directions, the optimum location is determined for specific agricultural land use types. This model includes the concept of economic rent which is the return received from working the land. A land use type will be economic in an area where transport costs do not

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exceed that return or revenue received. When transport costs and revenue are equal economic return is zero. Beyond this point, a more extensive land use type is more economic or profitable. As a result, with a single form of land use being carried out, such as market gardening, dairying and wheat, land use becomes more extensive the further from the market. A concentric zonal pattern of land use is said to develop on this isotropic surface. However, because the model has unrealistic assumptions, land use patterns are complicated by such factors as variations in topography and behavioural decisions by individuals. (see extensive farming/agricultural/ land use, intensive farming/ agricultural/land use)

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W

wadi — a dry river course typically found in arid areas. A wadi will flow only after a brief rainstorm Walker circulation — atmospheric circulation along the equatorial latitudes involving the ascent over the Indonesian sector and the subsidence over the eastern Pacific. The Walker circulation is not really one simple cell but a complex set of vertical motions involving the whole equatorial zone. When the Walker circulation is strong sea surface temperatures in the equatorial eastern Pacific are low, rainfall and cloudiness are low in the same area, but high over Indonesia and Australia. There are also associated anomalies of weather and circulation in many parts of the world. When the Walker circulation is weak the reverse anomalies occur. The strength of the Walker circulation fluctuates irregularly but with a 2–5 year period. Source: Climate Change and Variability, A.B. Pittock et al p. 180 C.U.P., 1978 (see atmsosphere, figure 23, ENSO, general circulation, Southern Oscillation) Wallace’s line — a line drawn by Alfred Russell Wallace to mark the boundary between distinctive fauna of the Asian and Australian continents. The line separates two classes of mammals – the predominantly marsupial of Australasia and the solely placental of Asia. The line follows a deep channel south of the Philippines between the islands of Borneo and Sulawesi and through to between Bali and Lombok Wallacea — the area making up thousands of islands between the edge

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of the Australian continental shelf (Sunda Land) and the mainland; ie between the Sunda and Sahul including the islands of Bali, Lombok, Flores and Timor. Wallacea was named after Alfred Russell Wallace who recognised the distinctive Asian flora and fauna north of this area and distinctive Australian flora and fauna south of this area. The line marking the boundary between these two sets of flora and fauna is known as Wallace’s line Walls of China — a landform resulting from the erosion of the lunette on the eastern side of Lake Mungo in the Willandra Lakes region of western New South Wales, Australia (see lunette, figure 39) warm front — the passage of a warm parcel of air overtaking colder more dense air. Just as with a cold front precipitation often results as air rises. However precipitation resulting from the passage of a warm front tends to last for a longer period of time and to be less intense than that resulting from a cold front. Warm fronts are not very common in Australia (see atmosphere, figure 50, figure 55) water cycle — see hydrologic cycle watershed — see catchment area water table — the upper part of the saturated zone of the regolith. Above the water table, evaporation is greater than the water received from ground water flow. Below the water table the input of ground water is greater than the rate of evaporation. The water table occurs where these two processes balance each other. The water table is normally very low in deserts because groundwater flow is very low and evaporation is very high; whereas in wetter or more humid areas


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the water table is much higher (such as a metre below the surface). Rivers indicate where the water table meets the surface WaterWatch — a management program in which local communities become involved in monitoring the state of their environment with the objective of promoting environmental awareness and improved environmental quality. Australian examples are Streamwatch (NSW) and Ribbon of Water (Western Australia) wave height — the vertical distance between the wave crest and the wave trough wavelength — the horizontal distance between successive crests or successive troughs — such as in ocean waves. Waves in the open ocean tend to have long wavelengths; as they approach shallower water near land the wavelength decreases and the wave height increases leading to the breaking waves along the coastline wave period — the time taken between two successive wave crests or two successive wave troughs wave refraction — the bending of the wave front as water depth decreases — when wave depth is less than half the wavelength. As waves approach the shoreline at an angle wave depth decreases reducing the speed of that section of wave; the rest of the wave moves forward; so the wave appears to bend WCED — see World Commission on Environment and Development weather — the condition of the lower atmosphere in the short-term – over a day, a week, or even the past month. Weather including precipitation, temperature, winds and humidity (see climate, relative humidity) weathering — the physical or chemical breakdown of materials into smaller materials (physical weathering) or simpler minerals (chemical weathering). Examples include frost shattering, insolation weathering, oxidation and carbonation

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weather map — see synoptic chart Weber, A — a German spatial geographer/ economist who, in 1905, proposed a theory of industrial location. He paid particular attention to the loss of weight and bulk associated with the processing of raw materials. He demonstrated that industries with large weight loss were resourceoriented. These industries tended to locate near the resource being processed (in order to reduce total costs) Wegner, A — a German meteorologist/ geologist who, in 1915, first elaborated on the concept of continental drift. He noted the remarkable similarity between the geology, flora as well as the shapes of the opposing coasts of Africa and South America. He later suggested that a supercontinent, Pangaea, began to break up about 200 million years ago. His then controversial theory did not gain acceptance until the late 1960s. The weight of supportive evidence confirmed the concept of continental drift. In this same period two other Earth Scientists, Harry Hess and J. Tuzo Wilson, suggested the method of such drift with the mechanism involving crustal plates and mid-ocean ridges. The concepts of plate tectonics and sea floor spreading were born West Antarctica — that part of the Antarctic continent that extends along its Southern and Indian Ocean coastlines from the Ross Ice Shelf to the Ronne Ice Shelf. West Antarctica forms the bulk of the area of Antarctica (see East Antarctica) West Asia — that part of Asia comprising Afghanistan, Tajikistan, Kyrgyzstan, Kazakhstan, Uzbekistan, Turkmenistan, Azerbaijan, Iran, Iraq, Syria, Jordan, Israel, Saudi Arabia, Yemen, Oman, United Arab Emirates, Qatar, Bahrain and Kuwait (see South Asia, Southeast Asia, East Asia and North Asia)

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West Bank — disputed territory between Israel and Jordan east of the Jordan River. Following the wars of 1967 and 1973, Israel occupies much of the West Bank with Israeli populations replacing those of Palestinians. The Golan Heights to the northeast of the Sea of Galilee is also in dispute between Israel, Lebanon and Syria west wind drift — a slow easterly flowing ocean current driven by the westerly winds between latitudes 45ºS and 55ºS approximately wetlands — any area of flat land that is permanently or temporarily covered by shallow water eg mangroves and swamps (Figure 60 colour). Wetlands are common along coastal areas such as in estuaries, where the rise and fall of tides lead to inter-tidal mangroves. Riverine wetlands, which are permanently under water, form along rivers. Wetlands are also located along the edges of, and within, inland lakes White Australia Policy — the name given to the Federal Government policy of the early to mid twentieth century that excluded immigration of people of non-British or European descent into Austraia WHO — World Health Organisation wilderness — an area which is in its natural state with no human activity windchill — the cooling effect of wind on a surface. The surrounding air temperature might be 8°C but because of the presence of a wind the actual temperature felt by the skin might be 3°C this is because the wind evaporates moisture from the skin and evaporation is a cooling process. The difference in air temperature and that actually experienced is the result of the ‘windchill factor’ (see atmosphere) wind tunneling — the acceleration of wind caused by its path between buildings — such as between tall buildings within the CBD wind power — the generation of electricity by windmills harnessing the 174

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power of winds by turning turbines. The generation of wind power is a pollution-free, renewable form of energy. It is used to supplement more traditional energy sources in areas where constant and reliable winds blow unimpeded by mountain barriers eg latitude 40°–50° North and South (southwestern Western Australia, the Netherlands in northern Europe and Chile in South America) wind rose — a type of graph indicating the direction from which winds blow towards a point. In more detailed wind roses, wind strength and the percentage of times that winds blow from a particular direction are given winter solstice — an event that is the result of the Earth’s revolution around the Sun. In the Southern Hemisphere, this event occurs 21-22 June. At this time the Sun is directly overhead at latitude 23½°N (Tropic of Cancer); this is known as the shortest day of the year in the Southern Hemisphere. The area south of the Antarctic Circle (latitude 66½°S) receives no direct sunlight Wollemi Pine — a new species of tree, discovered in 1994, northwest of Sydney, NSW. The tree grows up to 35 metres high. The species has survived for over 100 million years woodchipping — the process of cutting trees into smaller units for use in industry World Bank — an international agency. The World Bank provides long term loans to countries that cannot pay commercial rates of interest (see International Monetary Fund) world city — a major city of the world with international linkages and influence such as significant economic and political ties; such cities include New York, London and Tokyo. These cities occupy a distinctive niche as a result of their role as political and financial control centres. Their status is confirmed by concentrations of producer services such as education, research and development, banking, accounting, legal services, advertising and real estate


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World Commission on Environment and Development — a United Nations organisation established by the United Nations General Assembly in 1983. The WCED is concerned with identifying changes in, and threats to, environmental quality and the quality of life of people around the world. Its famous 1987 publication, Our Common Future, showed and explained to the world the state of the planet and the need for effective social and political action and cooperation in order to halt the global degradation of both natural resources and the quality of people lives. The WCED is more commonly known as the ‘Brundtland Commission’ after its chairperson Gro Harlem Brundtland, former Prime Minister of Norway World Conservation Strategy — throughout the 1980s and 1990s and into the 21st Century people’s attention has increasingly been focused on the plight of natural resources and the quality of the natural environment in which they live. A World Conservation Strategy was published in the early 1980s to promote the wise use of the biophysical environment and its resources following principles such as environmental sustainability. The WCS provided a strategy for governments, industry, communities as well as individuals to better utilise natural resources and to ensure their long-term viability (see National Conservation Strategy, sustainable development, sustainable yield) World Conservation Union — see IUCN world economy — the capitalist economic system that has emerged since the Middle Ages linking

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countries into a global economy in which different countries occupy different positions in terms of levels of development, political systems and resource endowment World Heritage List/site — in 1972 The Convention Concerning the Protection of the World’s Cultural and Natural Heritage (The World Heritage Convention) was adopted by UNESCO. The Convention aims to protect sites of significance that are recognised worldwide (not just by a country) and are of a concern to all people. A World Heritage List has been established. Over 400 sites worldwide have been designated as World Heritage Sites. These include the Grand Canyon USA, The Great Wall of China, and Stonehenge in England. In Australia, World Heritage sites are: the Great Barrier Reef (1981), Kakadu National Park (in three stages 1981, 1987, 1992), Willandra Lakes Region (1981), Lord Howe Island Group (1982), Tasmanian Wilderness (1982 and twice in 1989), Australian East Coast Temperate and Subtropical Rainforest Park (1986, 1994), Uluru-Kata Tjuta National Park (1987, 1994), Wet Tropics of Queensland (1988), Shark Bay (1991), Fraser Island (1992), Australian Fossil Mammal Sites: Riversleigh/Narracoorte (1994), Heard and MacDonald Islands (1997), and the Greater Blue Mountains Area (2000) World Trade Organisation — an international organisation with the aim of encouraging international trade via the removal of trade barriers WTO — see World Trade Organisation WWF — World Wide Fund for Nature (formerly the World Wildlife Fund)

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X

Xanthorrhoea — a native Australian plant more commonly known as a ‘Grass Tree’, ‘Kangaroo Tail’ and ‘Black Boy.’ It is not a grass or a tree but is more closely related to the lily. The Xanthorrhoea is well adapted to the dry, exposed environments such as on the top of exposed plateau surfaces. It is well adapted to fire with its thick bark insulating its interior. It sometimes burns to ground level but sprouts immediately after rain xanthozem — a deep yellow highly structured clay soil with increasing clay content with depth dominated by sesquioxides. It has a differentiated profile — upper clay-loam A-horizon to a medium-heavy clay B-horizon, strongly pedal with an acid pH (see kraznozem, residual site) xenoalpine — those insects in high altitude areas that have ‘accidentally’ found their way into alpine areas but do not become established xenolith — a piece of surrounding rock (called country rock) incorporated into an intrusion such as a dyke

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xeromorphic — possessing features similar to xerophytes xerophyte — a plant adapted to dry conditions such as in arid environments. Examples include cactus and spinifex (see plant succession, sere) xerophytic — having the characteristics of being able to adapt to dry conditions (see arid environment, xerophyte) xerosere — the stages in plant succession in an arid environment xerothermic — a warm-dry period Xi’an — capital of Shaanxi Province in central China. This is the site at which the buried terracotta warrior ‘army’ of the emperor Qin was discovered in 1974 x-ray art — a style of artwork originally practised by Aboriginal groups in Australia especially of animals in their immediate environment. Typically, the spine and other bones and internal organs are shown as well as the outlined exterior of the figure


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arynew geography dictionary ewgeography dictionary new hydictionary new geography

Y

Yanomami — the largest Indian nation in Brazil. Initial substantive contact with Europeans was in the 1950s. The Yanomami people have been in conflict with the Brazilian Government since the 1970s due to a proposal to open up the Amazon via a national highway through Yanomami traditional land. During this time, disease decimated the indigenous people. In 1992 however the Brazilian Government set aside 94,000 km2 of northern Brazil for the Yanomami nation (see indigenous people, maloca) Yap — one of the Caroline Islands in the western Pacific Ocean — part of the US-administered Trust Territories of the Pacific Islands yardang — a landform typical of arid environments. Wind carries sand just above the ground which, in turn, abrades the surface forming long grooves in the rock surface with sharp ridges between these grooves (see abrasion) yield — the output or production expressed in relation to a unit of input. For example in relation

agriculture, the amount of produce from crops or cattle may be expressed in terms such as 20 kilograms per hectare (20kg/ha), or 5 litres per day; 100 kg per km2 (see sustainable yield) young population — the population of a community, such as a country, is considered ‘young’ if the proportion of young people (ie those under 15 years of age) is greater than the 30% of the total population AND the proportion of older people (aged over 65 years of age) is less than 6% of the total population. Many developing countries have young populations as a result of factors such as rising birth rates. The rapidly declining birth rates of developing countries such as Australia is leading to ageing populations (see old population, population, population pyramid) Yucatan Peninsula — an area of Mexico thought to be the site of a large meteor impact approximately 65 million years ago. The resultant impact is suspected to have led to a major global extinction event that included the dinosaurs Yunnan — a Province in southwest China

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Z

zenith — the point in space that is vertically overhead. The point directly above an observer at 90°N is called the zenith; the point at 90°S is called the nadir zero tillage — where the land is not ‘tilled’ (such as ploughed) before the planting of crops zetaform beaches — along many coastlines headlands are separated by long sandy beaches which are asymmetrical when viewed from above – taking on a half-heart shape (Figure 61 colour). On beaches that are affected by constant swell, waves are refracted around headlands. A very tight curve near one headland contrasts with a long sweeping beach towards the other headland (see wave refraction) zonal flow — any flow of water or air circulating along a straight line such as a line of latitude. The circulation of westerly winds between latitide 35°–55° North and South and the flow of air along the equator from east to west are examples of zonal flow zone of aeration — the zone immediately below the ground surface in which the spaces between soil particles are partially filled with air and partially with water zone of saturation — the zone below the ground surface in all spaces between soil particles are filled with water. The top of the zone of saturation is called the water table. The water contained within the zone of saturation is called groundwater zone of transition — an area or zone that is experiencing gradual change. For example, the transition that occurs from a dominantly rural to dominantly urban on the rural-urban fringe. The term was originally applied 178

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to the area around the CBD of the concentric zone model representing a mix of industrial, commercial and older residential land use. It is now more commonly used to describe areas of gradual change from one extreme to another such as the transition from an arid climate to a more humid climate zonal model of soil formation — a model suggesting that soils form under so called ‘normal’ conditions of slope, drainage and rock-type and show broad similarities across the globe. These reflect patterns of climate and vegetation on a world scale – eg chernozems of the grasslands of North America and the Ukraine steppe and the podsolised soils of the temperate forests. The zonal model of soil formation is increasingly being challenged as an effective tool to describe and account for soil types because of its circular arguments. More recent models highlight the significance of local soilforming factors such as parent material, slope and biological action. Similarly local earth-surface processes such as soil creep and slopewash are addressed rather than vertically operating processes of eluviation and illuviation being exclusively treated (see azonal soil, duplex soil, intrazonal soil, podsol) zonda — a warm, humid wind from the north in Argentina and Uruguay zoogeography — the study of the location and distribution of animals over the Earth zoophyte — an animal that resembles a plant (eg a coral polyp) ZPG — zero population growth; where parents have only the number of children needed to maintain the existing population number


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WORLD RECORDS ATMOSPHERE Highest Average Annual Rainfall Lowest Average Annual Rainfall Driest Continent Highest recorded Temperature Lowest Recorded Temperature Most Consecutive Sunny Days Most Rainy Days per year Least Sunshine on Earth Highest Average Annual Rainfall Recorded in Australia Highest Recorded Temperature in Australia Lowest Recorded Temperature in Australia Windiest Place

Mawsynram (India) 11,873 mm Antfagasta (Chile) 0–0.1 mm Antarctica, less than 50mm per annum Azizia (Libya) 58°C Vostok (Antarctica) -89.2°C St. Petersburg (Russia) 768 between 1967 and 1969 Mt Wai’ale’ale (Hawaii) up to 350 rainy days South Pole (182 days without sunshine) Babinda (Queensland) 4573mm Cloncurry (Queensland) 53.1°C Charlotte Pass (NSW) -23°C Mt Washington (USA) winds 371 km/hr

LITHOSPHERE Largest Continent Largest Desert Largest Hot Desert Highest Mountain Highest Marine Mountain Highest Plateau Largest Delta Largest Island Largest Sand Island Largest Archipelago Largest Active Volcano Largest Cave Longest Gorge Longest Fiord Longest Mountain Range Deepest Point on Earth Lowest Point on the Earth’s Surface Highest Mountain on the Australian Mainland Highest Mountain on Australian Territory

Asia 43,608,000 km3 Antarctica, 14.9 million km2 Sahara Desert (North Africa) 9,269,000 km2 Mt Everest (Tibet/Nepal) 8848 m Mauna Kea (Hawaii) 10,205 m (of which 4205m is above sea level) Tibet 4875 m Ganges/Brahmaputra Delta (Bangladesh) 75,000 km2 Greenland (North Atlantic Ocean) 2,175,000 km2 Fraser Island (Queensland, Australia) 1662 km2 Indonesia, over 13,000 islands Mauna Loa (Hawaii) 6000 km2 Sarawak Chamber (also Lubung Nasib Bagus) (Malaysia) 700 m long, 70 m high with an average width of 300m Grand Canyon (USA) 446 km Nordvest Fiord (Greenland) 313 km Andes (South America) 7240 km Mariana Trench (western Pacific Ocean) 11,032 m Dead Sea (Israel) 398 m below sea level Mt Kosciuszko (NSW) 2228 m Big Ben (Heard Island) – Mawson Peak at 2745 m

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HYDROSPHERE Longest River Largest River Discharge Highest Waterfalls Largest Freshwater Lake Deepest Lake Highest Lake Largest Atoll Largest Ocean Smallest Ocean Largest Marine Park Tallest Geyser Longest Glacier on Earth Longest River in Australia

Nile River (Barundi to Egypt) 6670 km Amazon River (Brazil) 6500 km3 per year Angel Falls (Venezuela) 807 m Caspian Sea (Kazakstan, Turkmenistan, Iran, Azerbaijan, Russia) 371,800 km2 Lake Baykal (Russia) 1637 m Lake Titicaca (Peru/Bolivia, South America) 3810 m above sea level Christmas Island (Kiritimai since 1985) 94 km2 Pacific Ocean, 166,241,700 km2 Arctic Ocean, 13,223,700 km2 Great Barrier Reef Marine Park (350,000 km2) Steamboat Geyser (Yellowstone National Park, USA) 60–120 m Lambert Glacier (Antarctica) 3000 km Murray-Darling 3750 km

BIOSPHERE Largest National Park in Australia Largest Flower Largest Rainforest area Biggest Animal on Earth Fastest Land Mammal Tallest Tree Oldest Living Tree

Kakadu National Park (Northern Territory) 19,800 km2 Rafflesia arnoldii (Indonesia/Malaysia) 91 cm flower bloom Amazon Basin Blue Whale Cheetah Mendocino Tree, California (112 m) Redwood, California (USA) – 72 m

URBAN Largest Country by area Smallest Country by area Largest Country by Population Smallest Country by Population Most Densely Populated Country Least Densely Populated Country Most densely Populated Island Largest City by Population Most Northern Capital City Most Southern Capital City Longest Railroad Longest Fence

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Russia, 17,078 005 km2 Vatican City (Rome) 0.4 km2 China, 1.2 billion people Vatican City (Rome) 834 people Monaco (France) 14,237 people per km2 Western Sahara (Africa) 0.7 people per km2 Java (Indonesia) 898 people per km2 Tokyo (Japan) 28,447,000 Reykjavik (Iceland) 64°09'N 21°57'W Wellington (New Zealand) 41°18'S 174°47'E Trans-Siberian Railway (Russia) 9437 km Dingo Fence (Australia)

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SITES OF INTERNATIONAL SIGNIFICANCE Seven Wonders of the World Pyramids of Egypt Temple of Artemis (Diana) at Ephesus The Colossus of Rhodes The Mausoleum at Halicarnassus The Phaos or Lighthouse of Alexandria The Statue of Zeus at Olympia The Hanging Gardens of Babylon

Seven Wonders of the Ancient World Temple of Abu Simbel (Egypt) Temple of Angkor Wat (Cambodia) Monoliths of Rapa Nui (Easter Island) Throne of Persepolis (Iran) Taj Mahal (India) Leaning Tower of Pisa (Italy) Great Wall of China

World Heritage Sites (Australia) Great Barrier Reef (1981) Kakadu National Park (1981, 1987, 1992) Willandra Lakes region (1981) Western Tasmania Wilderness National Parks (1982, 1989) Lord Howe Island Group (1982) Ulura-Kata Tjuta National Pak (1987, 1994) Central Eastern Rainforest reserves (1986, 1994) Wet Tropics of Queensland (1988) Shark Bay (1991) Fraser Island (1992) Riversleigh/Naracoorte Fossil Mammal Sites (1994) Heard and MacDonald Islands (1997) Macquarie Island (1997) Blue Mountains (2000)

Seven Natural Wonders of the World Himalayas and Mt Everest Victoria Falls Grand Canyon Great Barrier Reef Niagara Falls Paricutín (volcano) Iguaçu Falls

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CONVERSION TABLES Abbreviations millimetre centimetre metre kilometre gram kilogram litre millilitre kilolitre hectare hectopascal

Prefixes

mm cm m km g kg l ml kl ha hPa

mega kilo hectodeka decicentimillimicron

M k h da d c m

one million one thousand one hundred ten one tenth one hundredth one thousandth one millionth

106 103 102 101 10-1 10-2 10-3 10-6

Length 1 millimetre 1 centimetre 1 metre 1 kilometre 1 inch 1 foot 1 yard 1 statute mile 1 nautical mile 1 fathom

â&#x20AC;&#x201D; 10 mm; 100 cm; 1000 m; 2.54 cm; 0.0245 m 0.304 m 0.9144 m 1609 m; 1.609 km; 1852 m; 1.85 km; 1.83 m;

0.03937 inches 0.394 inches 39.37 inches; 3.281 feet; 1.094 yards 0.621 miles; 1094 yards; 3218 feet

5280 feet 6076 feet 6 feet

Area 1 hectare = 10,000km2 (100m x 100m) = 2.47 acres 1 kilometre = 10,000,000 m2 1cm2 = 0.1550 inches2 1m2 = 10.76 feet2 = 1.2 yards2 1km2 = 0.3861 miles2

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1 inch2 = 6.452 cm2 1 foot2 = 929 cm2 1 acre = 4047 m2 1 mile2 = 2.590 km2 = 2,590,000 m2 = 640 acres


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Velocity 1 knot = 1 nautical mile per hour = 1 metre per second = 3.328 feet per second = 2.24 miles per hour 1 kilometre/hour = 0.621 miles/hour 1 mile/hour = 1.61 kilometres/hour

Volume 1cm 1metre3 1 kilometre3 1 inch3 1 foot3 1 yard3 1 mile3 Liquid volume one imperial gallon 3

= = = = = = =

0.06102 inches3; 0.000001m3 435.31 feet3; 1.308 yards3 0.239 metres3 16.39 cm 0.02832 metres3 0.7646 metres3 4.17 kilometres3

= 4.55 litres

Mass 1 gram 100 grams 1 kilogram 1 tonne 1 ounce 1 pound 1 ton

= = = = = = =

0.0353 ounces 3.5 ounces 1000 grams; 2.20 pounds 1000 kilograms; 0.984 tons 28.3 grams 454 grams 1.02 tonnes

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Temperature Freezing point of water = O°C = 32°F Boiling point of water = 100°C = 212°F °C = 5/9 x (°F - 32) °F = 9/5 x °C + 32

Scale Equivalents Ratio

Representative Fraction

Statement

1:10

1/10

one centimetre represents 10 cm (or 0.0001 km)

1:100

1/100

one centimetre represents 1 metre (or 0.001km)

1:1000

1/1000

one centimetre represents 10 metres (or 0.01 km)

1:10,000

1/10,000

one centimetre represents 100 metres (or 0.1 km)

1:100,000

1/100,000

one centimetre represents 1000 metres (or one kilometre)

1:1,000,000

1/1,000,000

one centimetre represents 10,000 metres (or 10 kilometres)

0

1

2

Line scale 3 4

5

kilometre

184

Ratio

Statement

1: 100,000

one centimetre represents one kilometre

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POPULATION OF THE COUNTRIES OF THE WORLD AND THEIR RANKING BY SIZE, 1999 AND 2050 Country or area World Afghanistan Albania Algeria American Samoa Andorra Angola Anguilla Antigua and Barbuda Argentina Armenia Aruba Australia (1) Austria Azerbaijan Bahamas Bahrain Bangladesh Barbados Belarus Belgium Belize Benin Bermuda Bhutan Bolivia Bosnia and Herzegovina Botswana Brazil British Virgin Islands Brunei Darussalam Bulgaria Burkina Faso Burundi Cambodia

Population (thousands) 1999 2050 5,978,401 8,909,095 21,923 61,004 3113 4322 30,774 57,731 66 201 75 165 12,479 36,901 8 13 67 79 36,577 54522 3525 3996 98 347 18,705 25,761 8177 7094 7697 9981 301 485 606 992 126,947 212,495 269 288 10,274 8330 10,152 8918 235 477 5937 15,620 64 82 2064 5687 8142 16,967 3839 3767 1597 2798 167,988 244,230 21 46 322 528 8279 5673 11,616 35,491 6565 15,571 10,945 20,700

1999

Ranking 2050

45 129 34 202 198 61 221 201 31 125 191 51 85 88 173 161 8 177 73 75 178 100 203 140 86 118 145 5 213 172 84 63 94 68

25 132 29 191 194 50 220 205 32 135 182 63 112 95 173 160 8 186 102 99 174 77 203 116 72 137 143 7 207 171 117 52 78 68

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POPULATION OF THE COUNTRIES OF THE WORLD AND THEIR RANKING BY SIZE, 1999 AND 2050 Country or area Cameroon Canada Cape Verde Cayman Islands

Population (thousands) 1999 2050 14,693 37,290

1999 59

Ranking 2050 48

30,857

42,311

33

41

418

869

168

164

37

102

208

201

Central African Republic

3550

7689

124

108

Chad

7458

19,693

89

69

152

173

186

193 65

Channel Islands Chile

15,019

22,215

58

1,266,838

1,477,730

1

2

6801

6664

93

114

Colombia

41,564

71,550

27

22

Comoros

676

1577

159

150

2864

8597

131

101

19

28

214

215 111

China China Hong Kong SAR (2)

Congo Cook Islands Costa Rica C么te d'Ivoire Croatia Cuba Cyprus

3933

7195

117

14,526

30,470

60

58

4477

3673

113

138

11,160

11,095

65

90

778

913

157

163

Czech Republic

10,262

7829

74

106

Dem. People's Rep. of Korea

23,702

30,770

41

57

Dem. Republic of the Congo

50,335

160,360

24

10

5282

4793

105

123

629

1346

160

155

71

79

200

204

8364

12,265

83

85

871

1387

154

154 67

Denmark Djibouti Dominica Dominican Republic East Timor Ecuador

12,411

21,190

62

Egypt

67,226

114,844

15

16

6154

11,237

97

89 159

El Salvador Equatorial Guinea

442

1122

165

Eritrea

3719

9085

121

98

Estonia

1412

927

146

162

61,095

169,446

18

9

43

34

206

213

Ethiopia Faeroe Islands Falkland Islands (Malvinas) Fiji Finland

186

2

3

224

224

806

1310

156

156

5165

4898

106

121

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POPULATION OF THE COUNTRIES OF THE WORLD AND THEIR RANKING BY SIZE, 1999 AND 2050 Country or area France

Population (thousands) 1999 2050 58,886 59,883

1999 20

Ranking 2050 26

French Guiana

174

581

184

170

French Polynesia

231

388

179

180

Gabon

1197

2682

149

146

Gambia

1268

2773

148

144

Gaza Strip

1077

4772

152

124

Georgia

5006

5180

107

119

Germany

82,178

73,303

12

21

Ghana

19,678

51,802

49

35

Gibraltar

25

18

212

219

10,626

8233

71

104

Greenland

56

63

205

206

Grenada

93

115

194

197

450

601

164

167 188

Greece

Guadeloupe Guam

164

266

185

11,090

27,165

66

61

Guinea

7360

16,348

90

75

Guinea-Bissau

1187

2685

150

145

855

1166

155

157

8087

15,174

87

79

--

1

227

227

6316

13,920

96

82

10,076

7488

76

109

Guatemala

Guyana Haiti Holy See (3) Honduras Hungary Iceland

279

341

175

183

India

998,056

1,528,853

2

1

Indonesia

209,255

311,857

4

5

Iran (Islamic Republic of)

66,796

114,947

16

15

Iraq

22,450

54,916

43

31

3705

4710

122

128

Ireland Isle of Man

78

104

196

200

6101

9440

99

97

57,343

41,197

22

44

2560

3801

135

136

126,505

104,921

9

17

6482

16,547

95

73

Kazakstan

16,269

18,665

54

70

Kenya

29,549

51,034

35

37

Kiribati

82

155

195

195

Israel Italy Jamaica Japan Jordan

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POPULATION OF THE COUNTRIES OF THE WORLD AND THEIR RANKING BY SIZE, 1999 AND 2050 Country or area Kuwait

Population (thousands) 1999 2050 1897 3527

1999 143

Ranking 2050 140 110

Kyrgyzstan

4669

7375

111

Lao People's Dem. Republic

5297

13,344

104

83

Latvia

2389

1628

138

149

Lebanon

3236

5169

128

120

Lesotho

2108

4766

139

125

Liberia

2930

10,010

130

94

Libyan Arab Jamahiriya

5471

11,005

101

91

32

42

210

210

3682

2967

123

142

426

430

167

176

Liechtenstein Lithuania Luxembourg Macau

467

488

163

172

Madagascar

15,497

40,438

57

46

Malawi

10,640

29,008

69

60

Malaysia

21,830

36,989

46

49

Maldives

278

680

176

166

10,960

31,353

67

56

Mali Malta Marshall Islands

386

421

171

178

62

182

204

192

Martinique

392

457

170

175

Mauritania

2598

6585

134

115

Mauritius (4)

1150

1440

151

153

97,365

146,645

11

11

116

254

189

189

Mexico Micronesia (Fed. States of) Monaco Mongolia Montserrat

33

41

209

211

2621

4398

133

130

11

11

218

221

Morocco

27,867

45,434

37

39

Mozambique

19,286

42,923

50

40

Myanmar

45,059

64 890

26

23

1695

3023

144

141

Namibia Nauru

11

24

219

217

Nepal

23,385

49,320

42

38

Netherlands

15,735

14,156

55

81

215

267

180

187

Netherlands Antilles New Caledonia

210

332

181

184

New Zealand

3828

5248

120

118

Nicaragua

4938

11,600

108

87

188

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POPULATION OF THE COUNTRIES OF THE WORLD AND THEIR RANKING BY SIZE, 1999 AND 2050 Country or area Niger

Population (thousands) 1999 2050 10,400 32,029

Nigeria

108,945

244,311

10

6

2

2

225

225

Niue Northern Mariana Islands

1999 72

Ranking 2050 54

74

402

199

179

Norway

4442

4758

114

126

Oman

2460

8310

136

103

152,331

345,484

6

4

19

45

215

208

Panama

2812

4263

132

133

Papua New Guinea

4702

9515

110

96

Paraguay

5358

12,565

103

84

Peru

25,230

42,292

38

42

Philippines

74,454

130,893

14

12 228

Pakistan Palau

Pitcairn (5)

--

--

228

38,740

36,256

30

51

Portugal

9873

8137

77

105

Puerto Rico

3839

4710

119

127 165

Poland

Qatar Republic of Korea Republic of Moldova

589

844

162

46,480

51,275

25

36

4380

4506

116

129

Reunion

691

959

158

161

Romania

22,402

16,419

44

74

147,196

121,256

7

14

7235

16,008

92

76

Russian Federation Rwanda Saint Helena (6)

6

10

223

222

39

36

207

212

152

242

187

190

7

8

222

223

Saint Vincent and Grenadines

113

140

190

196

Samoa

177

351

183

181

Saint Kitts and Nevis Saint Lucia Saint Pierre and Miquelon

San Marino

26

30

211

214

144

297

188

185

20,899

54,461

48

33

9240

23,135

80

64

77

115

197

198

Sierra Leone

4717

10,994

109

92

Singapore

3522

4015

126

134

Slovakia

5382

4836

102

122

Sao Tome and Principe Saudi Arabia Senegal Seychelles

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POPULATION OF THE COUNTRIES OF THE WORLD AND THEIR RANKING BY SIZE, 1999 AND 2050 Country or area Slovenia Solomon Islands

Population (thousands) 1999 2050 1989 1487

1999 142

Ranking 2050 152

430

1130

166

158

9672

31,835

78

55

South Africa

39,900

52,514

28

34

Spain

39,634

30,226

29

59

Sri Lanka

18,639

25,923

52

62

Sudan

28,883

59,176

36

27

415

588

169

169

980

2436

153

147

8892

8661

82

100

Somalia

Suriname Swaziland Sweden Switzerland

7344

6745

91

113

15,725

34,490

56

53

Tajikistan

6104

11,293

98

88

TFYR Macedonia (7)

2011

2302

141

148

60,856

74,188

19

20

4512

12,104

112

86

1

2

226

226

Syrian Arab Republic

Thailand Togo Tokelau Tonga Trinidad and Tobago

98

110

192

199

1289

1543

147

151 80

Tunisia

9460

14,983

79

Turkey

65,546

100,664

17

18

4384

7715

115

107

Turks and Caicos Islands

16

44

216

209

Tuvalu

11

28

220

216

Uganda

21,143

64,850

47

24

Ukraine

50,658

39,302

23

47

2398

3615

137

139

United Kingdom

58,744

56,667

21

30

United Rep. of Tanzania

32,793

80,584

32

19

United States of America

276,218

349,318

3

3

94

86

193

202 131

Turkmenistan

United Arab Emirates

United States Virgin Islands Uruguay Uzbekistan Vanuatu

3313

4362

127

23,942

40,565

39

45

186

428

182

177 43

Venezuela

23,706

42,152

40

Viet Nam

78,705

126,793

13

13

14

21

217

218

284

591

174

168

Wallis and Futuna Islands Western Sahara

190

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POPULATION OF THE COUNTRIES OF THE WORLD AND THEIR RANKING BY SIZE, 1999 AND 2050 Country or area Yemen Yugoslavia Zambia Zimbabwe

Population (thousands) Ranking 1999 2050 1999 2050 17,488 58,801 53 28 10,637 10,548 70 93 8976 21,204 81 66 11,529 18,139 64 71 Source: United Nations Population Division.

(1) (2)

Including Christmas Islands, Cocos (Keeling) Islands and Norfolk Island. As of 1 July 1997, Hong Kong became a Special Administrative Region (SAR) of China. (3) For Vatican City State. The population of the Vatican City State was under 500 persons in 1999. (4) Including Agalega, Rodrigues and St. Brandon. (5) The population of Pitcairn was 47 persons in 1999 and 2050. (6) Including Ascension and Tristan da Cunha. (7) The former Yugoslav Republic of Macedonia. Source: United Nations Population Division, The World at 6 Billion, United Nations, 1999, pages 12-18

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191


TEST