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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
The New Geography Dictionary
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