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Summer 2012

Olympic

special Planting schemes Air monitoring 3D geology

• Seafood fraud • Ancient tin mining • Southern Ocean art • Japanese tsunami •


About NERC The Natural Environment Research Council (NERC) is the UK’s main agency for funding research, training and knowledge exchange in environmental science. Our work tackles some of the most urgent and fascinating environmental issues we face, including climate change, natural hazards and sustainability.

NERC is a non-departmental public body. Much of our funding comes from the Department for Business, Innovation and Skills but we work independently of government. Our projects range from ‘blue-skies’ research to long-term, multi-million-pound strategic programmes, coordinated by universities and our own research centres:

NERC research covers the globe, from the deepest ocean trenches to the outer atmosphere, and our scientists work on everything from plankton to glaciers, volcanoes and air pollution – often alongside other UK and international researchers, policy-makers and businesses.

British Antarctic Survey British Geological Survey Centre for Ecology & Hydrology National Oceanography Centre National Centre for Atmospheric Science National Centre for Earth Observation

Editors Adele Rackley, 01793 411604 admp@nerc.ac.uk Tom Marshall, 01793 442593 thrs@nerc.ac.uk

Planet Earth is NERC’s quarterly magazine, aimed at anyone interested in environmental science. It covers all aspects of NERC-funded work and most of the features are written by the researchers themselves.

Science writer Tamera Jones, 01793 411561 tane@nerc.ac.uk Design and production Candy Sorrell, 01793 411518 cmso@nerc.ac.uk Print Gemini Press on 9 Lives 55 Silk, an FSC-accredited paper from responsible sources.

Contact us For NERC-funded researchers contact: editors@nerc.ac.uk To give us your feedback email: requests@nerc.ac.uk or write to us at Planet Earth Editors, NERC, Polaris House, North Star Avenue, Swindon SN2 1EU.

Front cover: The Olympic stadium – Populous/ London 2012

For the latest environmental science news, features, blogs and the fortnightly Planet Earth Podcast, visit our website Planet Earth Online at www.planetearth.nerc.ac.uk. Not all of the work described in Planet Earth has been peer-reviewed. The views expressed are those of individual authors and not necessarily shared by NERC. We welcome readers’ feedback on any aspect of the magazine or website and are happy to hear from NERC-funded scientists who want to write for Planet Earth. Please bear in mind that we rarely accept unsolicited articles, so contact the editors first to discuss your ideas. ISSN: 1479-2605


In this issue Summer 2012

Features

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8 Park life Planting for the Olympics, and beyond.

10 Something in the air

Keeping tabs on the capital’s atmosphere.

12 Grounds for success

How geoscience helped build the Olympic Park.

14 Sports shorts

More examples of environmental science links with sport.

16 Artists’ models

Turning climate science into art.

19 Tackling seafood fraud: fisheries forensics

Genetic tools to help tackle the scourge of illegal fishing.

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22 Visions of sustainability

Voices from the Planet Under Pressure conference.

24 Bogged down in history

Probing peat bogs for insights into ancient tin mining.

26 Waiting for the next big wave

The sediments left behind by the 2011 tsunami could help Japan be ready for the next one.

Podcast Q&A

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28 Revitalising urban rivers

How science has helped bring the River Wandle back from the brink.

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News Editorial T

here’s only a few weeks to go until the London Olympics and Paralympics, events which have been years in the making. Environmental science might not spring to mind when you think of all the work that’s gone into making the Games happen, so in Summer’s Planet Earth we touch on a few of the ways it has contributed to this huge project’s legacy. Aside from Olympic fever, other features illustrate more of the wideranging applications of NERC science – how new archaeological research is changing our understanding of ancient Britain’s role in European trade, and making sure your fish pie isn’t full of endangered species. We catch up

on tsunami research in the aftermath of last year’s massive earthquake in Japan. And if you think that science and art are unhappy bedfellows, our feature on Southern Ocean Studies might change your mind. Our podcast Q&A this month shows the benefits of genuine collaboration – understanding others’ needs, sharing expertise and working with a common purpose. In this case scientists, regulators and the public are working together to bring South London’s River Wandle back to life. We hope you enjoy this edition – and have a good summer. The Editors

Correction Please note that last issue’s feature on shale gas contained two editorial errors. On page 21, column 1, Cuadrilla’s estimate of gas in the Bowland Shale should be 5664 billion cubic metres (BCM), and the British Geological Survey estimate should be 133BCM. We apologise for this error.

Poisonous ladybirds stand out from the crowd B

right red ladybirds might look like easy prey for predators but they have a nasty surprise in store – it turns out that redder ladybirds are more poisonous than their duller companions. A study in Functional Ecology also shows they aren’t bluffing – their colourful bodies give predators an honest warning of their toxicity. But ‘for the last few years, evidence has

Antagain/istockphoto.com

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been growing that they’re not simple blocks of colour,’ says study lead author Dr Jonathan Blount of the University of Exeter. Many poisonous animals use bright colours and bold patterns to warn predators off. But the intensity of these signals varies between individuals, as do toxin levels; scientists weren’t sure why. The simplest possibility is that animals

rely on a single resource, perhaps energy from their diet, to produce both colour and toxin. By studying two groups of ladybirds raised on different diets, the researchers showed that ladybirds fed more aphids were redder and contained more of the toxin – they seemed to divide their resources between colour and poison. This demonstrates the link between pigment and toxin, supporting the researchers’ prediction that both were linked to the availability of resources. But why don’t less poisonous ladybirds just adopt bright red wing cases to fool predators into thinking they are toxic? It turns out that ladybirds that lie about their toxicity would quickly be found out. ‘The predators are constantly testing the signal; birds and other predators know that levels of toxicity are variable,’ says Dr Mike Speed of the University of Liverpool, the study’s co-author. Birds like starlings sometimes try out ladybirds they find, rejecting them only if they’re too toxic to eat.


Daily updated news @ www.planetearth.nerc.ac.uk

Ryan Bushby

Hummingbirds take no notice of flower colour

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ummingbirds ignore a flower’s colour when deciding whether to raid it for nectar. Instead, they seem to focus only on where it is. The birds see in colour perfectly well. But a paper in Animal Behaviour shows that location is a more reliable source of information and overshadows any information colour provides. ‘If they’ve fed from nectar-rich flowers before, that’s a more useful guide to whether those flowers will contain nectar in the future than colour is,’ says co-author Dr Sue Healy from the University of St Andrews. Colour can mislead because flowers on the same plant offer varying amounts of nectar; it’s better to rely on position alone. She and colleagues presented hummingbirds with four different types of artificial flowers. Some contained a 30 per cent sugar solution, while others contained just 20 per cent. They also varied how quickly the flowers refilled after the birds had taken their fill of sucrose. Some refilled after 10 minutes, others after 20 minutes. Seven of the birds took just 30 hours, during which they averaged 189 visits, to learn the difference between fast-filling and slower-filling flowers. One remarkable bird managed to learn the difference within 50 visits. But giving them clues about refill rates or concentrations using different colours made no difference to how quickly they learnt. ‘Ultimately, this suggests they ignore colour and just focus on location,’ Healy explains. Healy’s own observations confirmed this when she had to move nectar-containing feeders to keep them away from bears during previous experiments in Canada. ‘Even though we only moved the feeders by 20 to 50 centimetres, the birds just didn’t see them, because they weren’t in the same positions they expected to find them. So they just flew away, which was quite a surprise.’

Disease-spreading mosquito found in UK after 60 years A species of mosquito suspected of transmitting West Nile virus to humans in Europe has been discovered in the south-east of England. West Nile virus (WNV) lives primarily in birds. Humans occasionally catch it from the bite of a mosquito that has previously fed on an infected bird or animal. It can cause severe disease, but most infections are mild or produce no symptoms. The mosquito, known by its Latin name Culex modestus, can transmit WNV because it regularly bites both birds and mammals. WNV itself has never been found in the UK and there is no known current risk to humans. C. modestus hasn’t been seen in the UK since 1945, when a handful were recorded. The mosquitoes were found by Centre for Ecology & Hydrology (CEH) and University of Oxford postgraduate student Nick Golding. ‘It is unclear how long Culex modestus has been breeding in the UK – the new specimens were found during field studies in 2010 and 2011 – but it seems likely that it has arrived fairly recently,’ he says.

He found the insect’s larvae while researching how different mosquito species interact with other aquatic creatures. CEH colleague Stefanie Schäfer identified the species and then confirmed it by matching its DNA with examples from France. ‘I thought it looked a bit different,’ remembers Golding. ‘I was lucky to be looking for larvae because the adults of this species are much trickier to identify.’ Once notified of the potential health risk, the Health Protection Agency (HPA) confirmed the insect’s presence. Details of a study by CEH and the HPA appear in Parasites and Vectors. ‘In the UK, the mosquito’s biting habits and ability to transmit West Nile virus have yet to be investigated,’ explains Dr Miles Nunn, Golding’s supervisor at CEH. ‘Its discovery highlights the importance of expert long-term biological recording of UK wildlife by the scientific community.’ We’re not sure how these mosquitoes got to the UK. They can’t fly far so probably didn’t travel from mainland Europe under their own steam. It’s more likely they arrived by ship.

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News Dolphins introduce themselves with signature tunes W

ild dolphins use set melodies called signature whistles to introduce themselves to new acquaintances, researchers have found. They say the tuneful exchanges are an important part of a greeting sequence that lets dolphins recognise each other in the wild. ‘These signature whistles are special, because they contain the dolphin’s identity in the modulation pattern, or tune if you like, which the dolphin invents,’ explains Dr Vincent Janik from the University of St Andrews, who led the study, published in Proceedings of the Royal Society B. Signature whistles were first discovered in the 1960s. ‘Researchers had already brought up the idea that they’re whistles that dolphins use to identify themselves,’ Janik says. They’d also noticed captive dolphins using these whistles when apart from the rest of the group. But until now nobody had found them in the wild. ‘People thought that dolphins use signature whistles to update others about where they are. After all, they live in a 3D world, with no real landmarks,’ says Janik. ‘Beyond that, we didn’t know much about what they use signature whistles for.’ The team decided to analyse when and

how a 200-strong dolphin population around the east coast of Scotland uses them on encountering a new group. They expected all the pod’s individuals to introduce themselves. But instead it seems that it’s enough for just one dolphin to identify itself to elicit a reply from a member of the other group. ‘It’s like a greeting ceremony between a couple of individuals in two different groups. These individuals have a close interaction, but the others are more passive,’ says Janik. Dolphins have a huge repertoire of whistles, which make it hard to work out which one

was the signature. And the creatures whistle with a special structure in their foreheads, and don’t open their mouths. So once they had identified a signature whistle, the scientists then had to work out which dolphin it came from. ‘We used four sensors and then worked out the time of arrival of the whistle to say which dolphin made the tune,’ Janik explains.

First land plants triggered ice age

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he arrival of the first plants on dry land may have cooled the planet, pitching it into a series of deep cold spells, new research suggests. As plants spread across the landscape, they secreted organic acids to dissolve the silicate rocks they were growing on and unlock the nutrient minerals within. This accelerated the natural process of weathering, which absorbed carbon dioxide from the atmosphere. The plants also liberated other nutrients including phosphorus from the rock; these were washed out to sea, where they fed huge algal blooms. When these algae died, their bodies sank to the sea floor and were buried in sediment, locking away the carbon they’d absorbed while alive. The result of these processes was to deplete the carbon dioxide in the atmosphere,

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making the planet colder. The Earth’s climate gradually cooled during the Ordovician period, between 488 and 444 million years ago, eventually entering a series of short, sharp ice ages when glaciers covered much of the land. Scientists have long wondered why this happened, particularly as they think CO2 levels in the atmosphere were between 14 and 22 times current levels, and models suggest that needed to drop to around eight times to trigger glaciation. A study led by Professor Tim Lenton of the University of Exeter planted rocks with moss – not far off the kinds of plant that were growing in the Ordovician – and monitored the release of mineral nutrients. The results show that plants greatly accelerate this process – for example, the rate of phosphorus release increased by a factor of around 60.

They fed these results into a computer model to predict the effects of different levels of plant cover, finding that plants covering around 15 per cent of the land surface could have reduced atmospheric CO2 enough to make glaciation possible. Researchers already suspected plants played such a role in cooling the planet much later, in the Devonian period, between 400 and 360 million years ago. But this is the first time the earlier plants of the Ordovician have been implicated in triggering glacial takeovers. The end of this era was marked by a major extinction of marine species, so the paper’s authors write that ‘the evolution of the first land plants could have indirectly contributed to killing off many of their compatriots in the ocean.’ The paper appears in Nature Geoscience.


Daily updated news @ www.planetearth.nerc.ac.uk

Waste water gives clues to drug abuse A

new chemical analysis of sewage is giving detailed information about drug-abuse trends. The approach, pioneered by scientists at Bath and Huddersfield universities, can detect minute quantities of pharmaceuticals in waste water and could reveal whether they come from prescription drugs or illegal substances. It can even show how certain drugs, like cocaine, have been taken. The analysis relies on the fact that most drugs are chiral – their molecules come in two varieties that are mirror images of each other. These varieties are called enantiomers. The human body metabolises them differently, and excretes different chemicals as a result. Prescription and illegal drugs have different ratios of enantiomers, so by analysing the different chemicals in waste water the researchers aim to learn what drugs have been taken, and how they were made. This chemical analysis can then be compared to drug sales and prescription data for the communities using the tested waste water treatment plants. This approach is better than previous ways of estimating drug use from sewage, because of its potential ability to rule out substances that have been medically prescribed. It can also distinguish between the direct disposal of drugs (into toilets during police raids, for example) from their actual consumption. Forensic scientists already use chirality to determine whether particular drugs are legal or not, but this approach has never been used on sewage before. The technique, described in Science of the Total Environment, could be a powerful tool for spotting trends of drug use in populations, how drugs are being made and taken, and how strong they are It could also help understand drugs’ effects in the environment – on both humans and wildlife, and perhaps even to detect disease. Earlier research by the same team has shown that waste water treatment does not degrade the enantiomers of certain chiral drugs, such as antidepressants and beta-blockers, in the same way, so toxic forms can still end up in streams and rivers.

New RRS Discovery T

he new RRS Discovery was launched on 6 April from the Freire Shipyard in Spain. All the main equipment is installed and the ship is now being finished off ready for sea trials and delivery next year. The new research vessel replaces and updates the current Discovery, providing a state-of-the-art platform for the marine science community including better facilities for Remotely Operated Vehicles.

in brief . . . Space-weather warning system launches A new EU system to forecast space weather went live in March. The e2.54m SPACECAST project will provide frequent, reliable web-based forecasts of potentially dangerous solar activity, helping protect valuable satellites from electromagnetic radiation damage. SPACECAST uses data from satellites and ground-based measurements of the Earth’s magnetic field along with computer models to forecast space weather. This comes from changes in the Sun, which trigger magnetic storms around the Earth that have already caused millions of dollars of damage to satellites and can also threaten power grids and other vital infrastructure. The project is led by BAS researchers.

Fin trade blamed for blue shark decline Scientists say the market for shark-fin soup is the likeliest reason for the sharp drop in blue shark numbers over the last three decades. Researchers used satellite tags to track 16 sharks around Europe’s Atlantic coast, and mapped the results. They then compared the results with representations of where long-fishing boats tend to work. Hotspots of activity on the two maps correspond closely. The scientists don’t think the sharks are just being caught and killed by accident; instead they are being targeted for the Asian market in sharkfin soup, which accounts for most of the 60 million sharks being caught every year worldwide. They add that these regions would be ideal places to set up marine protected areas, where fishing is banned.

Science minister’s Antarctic trip Universities & Science Minister David Willetts has returned from a visit to the Rothera Research Station of British Antarctic Survey (BAS), where he experienced at first hand how polar scientists are contributing to the international effort to help society cope with climate change. His February visit marked the centenary of Captain Scott’s final expedition to the South Pole. While at Rothera, he met biologists studying how marine life is responding to environmental change, and talked to glaciologists about changes to the vast West Antarctic Ice Sheet and what they’ll mean for future sea-level rise.

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News Report uncovers global cost of ozone pollution missions of ozone are causing enormous harm to crops worldwide, a new study shows. Scientists from the universities of Leeds and York looked at records for six important crops – wheat, maize, soybean, cotton, potato and rice – from the 2000 growing season. They then used a model of global atmospheric chemistry to calculate the impact of different regions’ ozone emissions on agricultural yields around the world. The results, published in Biogeosciences, were startling. For example, if south-east Asia were to curtail all ozone emissions caused by humans, worldwide wheat losses from ozone could fall by more than half, and rice losses by more than 90 per cent. Some of the losses are concentrated in particular areas. North America is the biggest example; if its human ozone emissions stopped, European crop losses from ozone would fall by between 15 per cent and 63.2 per cent. Certain crops are hit particularly hard; North American pollution may cut European wheat production by up to 1.2 million tonnes a year. Europe’s pollution has less impact elsewhere, as atmospheric conditions typically don’t transport its ozone emissions as widely as those of other regions. ‘Our findings demonstrate that air pollution plays a significant role in reducing global

Andrii Iurlov/123RF.com

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crop productivity, and show that the negative impacts of air pollution on crops may have to be addressed at an international level rather than through local air-quality policies alone,’ says Dr Steve Arnold, of the University of Leeds, who led the study. Earlier research estimated that current crop losses from ozone in the same year were between 3.9 and 15.4 per cent for wheat and between 8.5 and 13.9 per cent for soybeans;

rice and maize both show lower but still significant losses. These losses have a huge worldwide cost – between $14 and $26 billion. Ozone doesn’t just damage plant life; it can also cause lung problems in humans. It is produced when chemical emissions like carbon monoxide, nitrogen oxides and socalled volatile organic compounds react in the presence of sunlight.

Seismic swarm shocks Islay R

eaders in the west of Scotland might have been shocked by a series of at least nine small earthquakes that struck the island of Islay in February, the largest of which had a magnitude of 2.8. Quakes of this size are unlikely to cause damage, though locals reported trembling houses, shaking roofs and rumblings like large tracked vehicles moving nearby. It’s possible that the largest event was followed by a series of aftershocks, which can happen for months after an initial earthquake as the ground adjusts to the change in stress. But it’s more likely Islay experienced an earthquake swarm. These are relatively

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common in Great Britain, though they’re generally of a much larger magnitude, and consist of a sequence of quakes clustered together with no clear distinction between the main shock and aftershocks. Seismic activity in and around Islay is relatively low, although there was a magnitude 3.4 earthquake off Jura in 1998. There have been larger earthquakes in Argyll in the recent past, including a magnitude 4.1 near Oban in 1986. The largest known Scottish earthquake was near Loch Awe in 1880, with a magnitude of 5.2. Islay earthquakes (green) and other seismicity (red).


Daily updated news @ www.planetearth.nerc.ac.uk

Scientists warn of emerging fungal peril F

Matthew Fisher

ungal diseases are a major threat – not just to wild plants and animals, but to us. A recent Nature paper shows we’re already heading for huge fungal damage to vital crops and ecosystems. If we don’t do more to stop these diseases’ spread, their impact could be devastating. Fungi already destroy some 125 million tonnes a year of rice, wheat, maize and potatoes and soybeans, worth $60 billion. Researchers estimate that in 2009-10, this could have fed 8.5 per cent of the world’s people. And this is just the result of persistent low-level infection; simultaneous epidemics in several major crops could mean billions starve. But the threat has gained a new urgency lately, and crops aren’t all that’s at risk. More and more of these killer fungi are appearing, and they’re increasingly attacking animals. Fungal epidemics already account for 72 per cent of extinctions from disease – more than bacteria and viruses put together. Amphibians are being wiped out at an unprecedented rate by a deadly chytrid fungus that’s been spread by the global animal trade; at least 500 species are thought to be at risk. Likewise, bats are succumbing to so-called White Nose Syndrome, which has spread across North America since appearing in 2006. ‘We’ve known for a long time about fungal pathogens like Dutch elm disease and potato blight,’ says Dr Mat Fisher, an expert in fungal infections at Imperial College London and one of the paper’s authors. ‘But we’re seeing more and more of these pathogens, and they are starting to affect animals in a way we’ve never seen before. The chytrid fungus has wiped out 40 per cent of amphibian species in some parts of Central America in just a few years, and we don’t know what the knock-on effects will be.’ New fungal diseases keep appearing, affecting organisms from bees and corals to sea otters. If we don’t do more to control them, we could see species wiped out all over the planet. In many cases there are direct consequences for humans. For example, bats eat insects that would otherwise attack crops; studies suggest White Nose Syndrome could end up costing farmers some $3.7

Midwife toad (Alytes obstetricans) mass mortalities in the Pyrenees caused by Batrachochytrium dendrobatidis.

‘Every lungful of air we take has fungal spores in it; the fact we survive shows we’ve had to evolve in the face of this constant fungal pressure. They’re always there, trying to occupy us – to them, we’re just nitrogen-rich patches of matter. Any weakness and they’ll get in and rot us away.’ Dr Mat Fisher, Imperial College London

billion a year. But even organisms that aren’t obviously useful to us will have unpleasant consequences somewhere down the line if they disappear. ‘Ultimately you can’t separate ecosystem health from human health – eventually, these birds will come home to roost,’ Fisher says, adding that the less diverse ecosystems become, the less they can stand up to sudden changes. Fungal diseases are even making climate change worse; scientists estimate that the trees they’ve affected would otherwise have absorbed 230-580 megatonnes of CO2 – around 0.07 per cent of the total in the atmosphere. It’s almost impossible to eradicate fungal disease in a wild population. But by tightening rules on the transport of plants and animals around the world, we could limit these pathogens’ spread into new areas. Why have fungi become so deadly? Many

have tough, long-lived spores, so they can survive without a host for much longer than most bacteria or viruses. Combined with our unprecedented levels of global trade and travel, this helps fungi reach new areas. Moreover, many fungi – particularly those that target animals – can infect several species. So they don’t depend on keeping a victim species alive, and can be spread by more resistant species to more vulnerable ones, wiping the latter out. And they are adept at swapping genes, so when we bring different fungi together, virulent combinations can result. Fisher says we need to start taking biosecurity more seriously – cutting down the amount of living material we transport around the world, quarantining what we do transport far more rigorously, and doing more to stop the illegal trade in plants and animals.

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OLYMPIC FEATURE

The Olympics will come and go, but their legacy will permanently transform the landscape of east London and the variety of plants and animals it supports. Horticultural ecologists Nigel Dunnett and James Hitchmough describe their contribution.

Park life T

he London Olympic Park in Stratford is the largest new urban park to be developed in Europe for 150 years. It is highly innovative, based on an ambitious longterm vision to create a world-class visitor destination and then to transform it into a park for local communities. One of the many things that set this project apart from a typical city park is that the whole plan, including the planting strategy, is dictated by the park’s Biodiversity Action Plan (BAP), which sets out the range of habitats and species the park needs to support. One of the planning conditions for the park was that it must provide 50 hectares of new habitat. In reality this means that most of the green space on the site must in some way contribute to the BAP. Given that the park and sporting venues will receive several million day-visitors over the period of the Olympics and Paralympics, this is a major challenge; we have to meet ecological goals and visitors’ aesthetic and recreational needs at the same time.

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Luckily this is an area we know a lot about. Much of our work focuses on delivering ecological benefits in everyday environments like parks, highways, gardens, schools and commercial areas, rather than in designated nature reserves or nature gardens which some people might never visit. This means we’re used to giving equal weight to aesthetics and ecological concerns. We were invited to be the park’s horticultural and planting design consultants in 2008, working with landscape architecture consortium LDA/Hargreaves. Our role has been to develop a planting strategy for the whole site for both 2012 and the subsequent two-year ‘transformation’ period, when the park will be converted to public use. Two parks in one The Olympic Park has two distinct areas. The north park is bigger and has an informal ‘country park’ approach, while the south park, which includes the main Olympic stadium, has a more urban, ‘festival’ feel. The vegetation and design of the two areas

reflect these different characters. The vegetation in the north park is dominated by designed versions of native UK habitats, and celebrates native biodiversity. These habitats include speciesrich meadows of different types, the largest area of wet woodland habitat in the UK, reedbeds, woodlands, flowering lawns and sustainable urban drainage features like rain gardens and bioswales (plant-filled depressions that help slow and clean water as it runs off the land). The south park focuses on visual drama. The Stadium Meadows are the largest areas of direct-sown annual meadows ever created in the UK and have seas of annual asters and daisies that are a magnet to pollinating insects. The 2012 Gardens are almost a square kilometre of stunning perennial plantings that celebrate the British gardening tradition and its exceptionally rich diversity of plants. Being able to work on site for the past two years has given us the opportunity for some trial and error, letting us make sure the park will be at its best when the games take place,


Images © ODA

in late July and August 2012. It hasn’t been easy, because most native flowers are past their best by this time, so we’ve focused our experiments on cutting back the meadows in spring to delay flowering into late summer. We’ve based our design and species choices on scientific research. Evidence for the value of urban gardens and native/exotic vegetation mixes to native invertebrates has come from projects like Biodiversity in Urban Gardens (BUGS), which investigated the variety of living things that city gardens support, and the complex relationships between them. We have also drawn on our own research projects and trials, such as work on the Bibury dataset – the longestrunning continuously-monitored experiment on herbaceous plant communities. Planting for the long game So how will we resolve the conflict between the immediate visitor experience and meeting BAP requirements over the longer term? The plan is for the vegetation to evolve and adapt, both naturally and through specific management plans, between the year

of the games and the long-term legacy phase, from 2014 onwards. During the transformation phase much of the hard infrastructure built for the games will be removed, and a number of things will happen to the vegetation once it has gone. For example, species-rich meadows have been created for 2012, containing little or no grass to maximise their flowering impact. During the transformation phase these will be oversown with more grass and other species so that they meet BAP requirements. The high-intensity spectator lawns sown for the games will also be made more diverse with a mix of oversowing and plug planting of more grass species. A second strategy is to create dramatic hotspots of colourful, non-native plants in both the north and south parks. Despite their drama and complexity, these are very naturalistic – closer to groups of plants in the wild than to typical garden planting schemes. This means they don’t need much maintenance at all compared to traditional park flowerbeds, and they support a wealth of biodiversity. In fact, there are no

municipal-style park plantings in our design at all; all the vegetation is innovative and sustainable. The Olympic Development Authority’s vision was that the park should play a central role in the London Olympics and beyond. The Olympic Park is unique in the UK, with innovation, sustainability, science, art and biodiversity all at its heart. It represents a potential turning-point in the way urban parks and green space are designed and managed. We hope it will become the benchmark for a new generation of urban green spaces that are both ecologicallyinformed and beautiful. n MORE INFORMATION Professors James Hitchmough and Nigel Dunnett are members of the Department of Landscape at the University of Sheffield. Email: n.dunnett@sheffield.ac.uk BUGS project: www.bugs.group.shef.ac.uk Nigel Dunnett homepage: www.nigeldunnett.info James Hitchmough homepage: www.landscape.dept.shef.ac.uk/james

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OLYMPIC FEATURE

Remember the headlines about air pollution in Beijing before the last Olympics? We might think London’s air is sweeter, but how can we be sure? Meteorologist Sylvia Bohnenstengel explains how she and colleagues will be monitoring the capital’s air quality in the run-up to London 2012.

Something in the air

Mark Thomas/Science Photo Library

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like going for a run after work and I enjoy living in a big town. The two do not always go well together. I worry about the polluted air I’m breathing in when my route hits the rush-hour traffic, but I’m lucky enough to work as an urban meteorologist at Reading University, so I get to take a closer look at exactly how air pollution affects us. In the run-up to the Olympics it’s not just hobby runners like me who are interested in pollution; top athletes are concerned about how it might affect their Olympic performance. The Chinese government took drastic measures to improve local air quality during the Beijing Olympics in 2008, including regulating traffic and even stopping building work. But our performance in sports is not the

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only reason we should care about air quality. Over 60 per cent of the world’s population lives in cities, and poor air quality can cause serious discomfort and damage health. It affects each of us in different ways every day – like during my run. For others it could be a life-or-death issue. I’m working on a two-year field campaign to measure air quality in London, called ClearfLo – Clean air for London. Why London? It’s one of the biggest cities in Europe and traffic is certainly having an impact on its atmosphere, so London needs well-informed air-quality regulations. And the Olympics offers a once-in-a-lifetime chance to see how local changes to London’s traffic routing might make a difference. London’s air has been monitored for more than 60 years, so you might wonder if this

hasn’t all been done before. But existing measurements don’t tell us about all the pollutants out there, or very much about why they are there. ClearfLo brings together scientists from all over the UK, Europe and US, with backgrounds in atmospheric chemistry, medicine and meteorology, to get a clearer picture of what’s going on. The more we know about these pollutants, and the physical and chemical processes they’re involved in, the better equipped we’ll be to mitigate their effects. We have set up air-quality monitoring stations across the city to measure the solid particles, ozone, nitrogen oxide and heat pollution over the city. Most of the stations are at ground level but a few are elevated, for example on top of the BT tower. With some readings being taken up to ten times


per second we’ll have a good insight into how pollutants are mixed up in London’s atmosphere and what happens when polluted air is blown into the city. Our monitoring sites include areas with lots of traffic – in Marylebone Road and The Strand – as well as urban locations in North Kensington which have less traffic. To see the differences between urban and rural pollution we are taking measurements in Detling, east of London, and Harwell and Chilbolton to the west. This will help us work out what’s in the air blowing into and out of London. We’ll be installing even more instruments during the Olympics to capture information

changes in pollution and wind. All this will help us build a 3D picture of the atmosphere and how it changes over time. In particular, we’ll be looking at three aspects of air pollution which have a strong bearing on human health. The first is the lifecycle of ozone. Longterm exposure to ozone causes lung damage and short-term, acute increases in its concentration can be fatal for vulnerable people. We already know that nitrogen monoxide and dioxide affect ozone concentrations, but there are other gases involved too, especially in polluted urban areas. One of these is the OH (hydroxyl) radical,

OVER 60 PER CENT OF THE WORLD’S POPULATION LIVES IN CITIES, AND POOR AIR QUALITY CAN CAUSE SERIOUS DISCOMFORT AND DAMAGE HEALTH.

on a wider range of pollutants. The Olympics will act as a real-life experiment, since the traffic flow will change considerably while the games are taking place. So we’ll be able to see how far air pollution can be mitigated by regulating the movement of vehicles around the capital. Because we can’t monitor every point in London we’ll fill in the gaps by running computer simulations and using remotesensing techniques such as lidar (light detection and ranging) to measure vertical

which is strongly reactive and can indirectly either form or destroy ozone by kicking off various chemical reactions. One of the sources of OH in urban areas is nitrous acid (HONO). Ironically we expect that HONO concentrations will increase as a by-product of modern emission-control technologies such as catalytic converters and particle filters. So we’re monitoring HONO at street level to see how OH is formed and lost, how it can change in the atmosphere, and how exactly it influences ozone.

Particulate matter (PM) poses different problems. These tiny particles, ranging from 0.0005 mm to 0.001mm across, can penetrate our lungs – the smaller the particle the deeper it can go – and can cause various problems in the lungs and heart. ClearfLo will help identify the mechanisms that make these particles grow and shrink; for instance our measurements already suggest that evaporation and condensation of water onto the particles might be an important factor. We need to understand more about the sources of PM too. It can come directly from burning fossil fuels, for example in cars and factories, as well as from natural sources such as volcanoes and vegetation. It can also form from volatile organic compounds (VOCs) which readily release molecules into the air. There are thousands of types of VOCs, both natural and man-made, that are currently not well understood or even known, and our monitoring will help to identify these sources. Thirdly, we’ll be looking at the influence of the weather. Pollutants are mixed in the first one to two kilometres of our atmosphere, in a layer which is topped by a sharp increase in temperature that acts like a lid, trapping pollution below. What happens in this layer is partly controlled by the energy released from the ground. This energy determines the height of the lid and also produces a distinct daily cycle; so during the day when the ground is warm the layer is deep and well mixed, which dilutes pollution, but at night as the ground cools the layer becomes shallower and pollution concentration increases. We’ll combine wind, air temperature and other measurements with a weather forecast model to understand as much as we can about these day/night variations and seasonal variations in different weather, so we can see what conditions make pollution worse. After two years of monitoring, ClearfLo will have produced an enormous body of data. Our comprehensive 3D picture of London’s atmosphere and air pollution will improve our computer simulation tools for weather forecasting. It will also mean we can give policy-makers the detailed and comprehensive information they need to create effective guidelines for keeping London’s air clean. And I might be able to find a healthier route for my evening run. n

MORE INFORMATION Sylvia Bohnenstengel works in the Department of Meteorology, University of Reading. Email: s.i.l.d.bohnenstengel@reading.ac.uk

Setting up the equipment in North Kensington.

www.clearflo.ac.uk

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OLYMPIC FEATURE

Grounds for success If you had to name the vital conditions for Olympic success, geological expertise probably wouldn’t be near the top of the list. But the London games couldn’t have happened without it. Kate Royse and colleagues from the British Geological Survey (BGS) explain why.

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he 500-acre Olympic Park sits in the Lower Lea Valley in London’s East End. Construction work has had to overcome problems like high groundwater levels, compressible soils – which threaten foundations and underground constructions – and contamination from pollutants like oil, petrol, tar, arsenic and lead, which pose serious risks to water supplies and ultimately human health if left untreated. In fact, all the major development projects that have been carried out in the run-up to the 2012 Olympics have involved construction on ground that engineers class as ‘difficult’. The Institution of Civil Engineers estimates that about half of all cost and time overruns on civil engineering projects are caused by ‘unforeseen ground conditions’. This is partly because too little is understood of 3D geology – of the ground’s physical, mechanical and chemical properties, and the processes acting on it. Traditionally, geological information has been displayed in two dimensions – as maps supported by cross-sections. Digital advances have allowed the routine use of Geographic Information Systems (GIS), which let us display and query an unlimited range of

spatial data. In this project, we have used 3D-modelling software to produce highresolution geological models of the shallow subsurface. The 3D models then had geotechnical and hydrogeological data added. They could then be used to predict not only the type of rocks and how they vary both vertically and laterally, but also the variation in their engineering properties – such as rock strength, shrink-swell characteristics and compressibility – and hydrological characteristics like how easily water passes through the ground. Finally, we combined our high-resolution 3D geological models with spatial data within a GIS in order to develop ‘intelligent’ map layers and systems that support planners by clarifying the consequences of different choices. Below are just three examples of how all our work can help developers. 3D models of the shallow subsurface Modelling the shallow subsurface can help predict potentially difficult engineering ground conditions by assessing the thickness, geometry and distribution of different types of rock (geological units). A full assessment of ground conditions using available borehole or trial pit data can be

used to help understand the nature of the ground before development starts. Each unit can be characterised in terms of the kinds of rock it contains and the layers it is made up of, as well as being attributed with a variety of information about properties such as strength, permeability and compressibility. 3D models in urban areas, such as the Lower Lea Valley, include information on the thickness and distribution of artificial ground – places where humans have changed the ground level, often by adding new material from elsewhere, and where there’s consequently now a higher risk of contamination and instability than elsewhere. This can be linked to the history of how the land has been used, letting us fully understand changes in the ground surface as a result of human activity. We can then use the 3D model to estimate the thickness of these deposits, giving the developer an indication of the cost of remedial measures at the beginning of the planning process. It can also help plan the ground-investigation phase which will ultimately result in significant savings of time and resources, as difficult ground conditions can be anticipated and planned for. ODA

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Screening for potential groundwater hazards Each period of industrial development has left its own contamination in urban areas. Regulators and planners need to know where these contaminants are, and assess the risk of them being be released into ground and surface waters by redevelopment. Contaminated areas are generally identified first through a detailed desk study and then by focused field investigation, which can be time-consuming and expensive. With this in mind, BGS developed an initial screening tool to help the planning community gauge potential contamination risks more quickly and effectively. The prototype for developing this tool was the Olympic Park site. Our tool uses GIS layers that have been integrated with the results of our 3D geological model, and brings together a range of geoscientific information, including data on geology, hydrogeology, rivers, flood potential, source protection zones (areas which provide groundwater for public consumption, such as around wells or springs), the sources and sizes of potential contaminants, and groundwater levels. The tool evaluates the source of possible pollution and the pathways (flooding, for example) that might move it to an area where it could affect people or the environment. We can then rank various proposed development scenarios according to our assessment of their potential to cause contamination, providing planners with a report on the spatial distribution of potential contaminant sources in their area, and the hazards associated with each. Finding drift-filled hollows A drift-filled hollow is a depression in the bedrock which has been filled with a

Hazard susceptibility map for drift-filled hollows in London.

mixture of unconsolidated materials like sands and gravel. The variability of these deposits, and the difficulty of predicting where they will occur, cause problems for engineers. These include foundations settling into the ground at varying rates in different parts of the building and instability in excavations and tunnels. The hollows can also form pathways for contaminants to travel into our groundwater supplies. Over the years, 31 of them have been revealed by development in London. In London and the Lower Lea Valley they are primarily found beneath the First River Terrace Deposit. At Blackwall, a drift-filled hollow was found which was over 60m deep and 475m wide. Their location is difficult to predict, but it has been shown that drift-filled hollows are typically found in certain areas. These include places where: there was once an artesian aquifer (where water pressure in the ground has the potential to rise above ground level); below a specific layer of river gravels (known as the Kempton Park Gravels); where the underlying layer of London clay is

less than 35m thick; within 300m of existing or former rivers; and near geological faults. We have used our 2D and 3D data within a GIS to create a map of areas of greater likelihood of drift-filled hollows. This gives planners a broader awareness of the potential location of difficult ground conditions associated with these features, presents information that can be used to reduce the potential for unforeseen ground conditions through effective site investigation, and improves our understanding of how driftfilled hollows are formed. 3D geological property modelling does not only allow geoscientists to present data in a more meaningful way to non-specialists. It is also a valuable scientific tool. In the long term, 3D geological models will give us a better understanding of the zone of human influence. It is clear that the scientific community needs to understand and be able to predict the effect that large-scale developments will have on the environment. Only the continued development of 3D models and the integration of currently separate geological disciplines will eventually allow us to answer these questions. n

MORE INFORMATION Dr Kate Royse manages the BGS Cities Underground project. Dr Vanessa Banks and Stephanie Bricker are hydrogeologists at BGS, and Andy Marchant works on its Geographic Information Systems.

3D geological model of the Lower Lea Valley, London.

Email: krro@bgs.ac.uk.

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OLYMPIC FEATURE

It’s easy to spot the importance of environmental science in this year’s Olympics and Paralympics; the Games have explicit sustainability goals, including minimising greenhouse gas emissions and waste, improving wildlife habitats and designing facilities that will cope with future climate change. The Olympics don’t come round that often though, and the sporting community uses environmental science more often than you might think. And it’s not all a one-way street – when a big event does come to town, environmental scientists don’t miss the chance to carry out unique experiments.

Sports shorts n The section of the Thames downstream from Eton Dorney Lake, site of the Olympic rowing events, is one of many sites monitored for water quality by the Centre for Ecology & Hydrology (CEH). With 30,000 spectators expected every day, the Games will be a great opportunity to see how an influx of people affects the Thames. n The Sports Turf Association and the Jockey Club both use the results of research into grass types and soil moisture to help them keep their turf as healthy as possible.

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n Walkers and climbers who use Harvey maps get access to geological information provided by the British Geological Survey (BGS). The maps include 3D images of each region, including reconstructions of the ice that sculpted the surrounding landscapes. n The UK’s winter sports prospects will get a boost from research on sea ice; UK Sport is using the work to better understand ice friction during high-speed events like the skeleton bob, which delivered the UK’s gold medal in the Vancouver Olympics in 2010.


n BGS used 3D modelling to help understand the subsurface geology of derelict and contaminated areas of Scotland’s Clyde Gateway regeneration area, which includes the main sites for the Glasgow 2014 Commonwealth Games. The work helped planners anticipate potentially difficult building conditions, ensuring a solid future for new facilities. n The GB alert system for nonnative species, run by CEH, brought sports at Grafham Water in Cambridgeshire to a halt when anglers spotted the invasive ‘killer shrimp’; the whole facility was shut for several days, with people’s boats quarantined inside.

n A two-year art project (right) inspired by the 2012 Paralympics, Look About – Transmission, will be on display at BGS’s offices during the Games. Artist Jon Adams uses geology to give new perspectives on disability and has incorporated modern-day ‘fossils’ such as hair clips, napkins and train timetables. BGS is a partner in the project, which is part of the London 2012 Accentuate programme to create a lasting legacy from the Olympic and Paralympic Games. n Using the Olympic Park as a test site, geologists developed a model that compares the carbon footprints of different ways of transporting aggregates to building sites from quarries around the

Images: ODA, VOJTa Herout/Shutterstock.com, istockphoto, Peter Hartley

n Tide and ocean-current information is crucial to sailors and sailing-race planners. NERC’s National Oceanography Centre worked directly with the British Olympic sailing team in their preparations for the Beijing Olympics. n Climate change is crucial for the survival of winter sports resorts over the next few decades. By understanding how annual snowfall is changing and the impact on sports fixtures and tourism, these traditionally snowbased economies can plan for a secure future.

UK. Planners can use the model to help find the most sustainable approach for future large-scale construction projects. n The new green areas being created around the Olympic Park could significantly improve Londoners’ comfort, health and energy use. An innovative climatemodelling tool shows these spaces will help counteract London’s ‘urban heat island’ effect, which makes the capital several degrees hotter than the surrounding countryside. This kind of ‘green infrastructure’ could be a good way for cities to cope with higher temperatures in the future.

n Confidence in the cleanliness of our rivers and lakes is crucial, not just for visitors to the UK countryside but for safe fishing, canoeing, kayaking, sailing and open-water swimming. n When researchers realised their technique for analysing carbonbased molecules would work on steroids, they began to adapt it into an anti-doping test. The approach is more accurate than usual ways of detecting synthetic steroids in urine, and could be in use in time for the 2016 Olympic Games.

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FEATURE

Artists’ models What happens when you take scientific data out of the lab and turn it into art? Artists Tom Corby, Gavin Baily and Jonathan Mackenzie, and polar scientist Nathan Cunningham asked that question, and the result was Southern Ocean Studies, a series of art installations that communicate environmental change in a completely new way. Adele Rackley finds out how they did it – and why.

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athan Cunningham, former head of the Polar Data Centre at the British Antarctic Survey (BAS), is a self-confessed computer geek. Data is his bread and butter, but he also has a strong personal interest in art, and explains that visualisation of data is something his team thinks about all the time. ‘Information is shared easily and quickly these days – Google Earth, social media and applications like iTunes don’t require people to understand complicated software. But science isn’t that good at putting complex ideas into context for the layman. We’re always thinking about better ways to

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make our data available.’ What Cunningham hadn’t thought about, until he met Tom Corby, was whether one good way of presenting data could be to turn it into art. Corby is an established artist with a longstanding interest in digital art and natural systems. He and long-term collaborators, graphic designer Jonathan Mackenzie and computer programmer Gavin Baily, had already begun to explore interactive ways of communicating environmental data with works such as cyclone.soc, which mapped internet chat-room debates about climate change onto real-time weather data. The strength of feeling surrounding the

theft of emails from climatechange researchers at the University of East Anglia had convinced Corby that this kind of data had developed a cultural life of its own. He wondered if climate models could be taken out of their scientific context and used to represent environmental change in ways that made it accessible to more people. The group pondered the potential of climate-model art over many cups of coffee. Climate models use mathematical equations to describe how atmosphere, oceans, ice, solar energy, organisms and landmass interact to produce Earth’s climate. Scientists use them to predict how


Data Landscapes, a series of watercolours based on Soviet-era climate-model outputs from the library at BAS, has been exhibited at art festivals around the world.

some variables, like changes in greenhouse gases, will influence climate systems. Models produce complex information, and understanding the results can be difficult without some knowledge of environmental science, the maths that underpins the model, and the graphical conventions used to represent the data. Even when it’s undergone some level of interpretation or simplification, usual ways of presenting climate data don’t give us any sense of the bigger picture and our own place in it. Together with ex-BAS scientist Claire Tancell, the group came up with a plan for a series of large-scale projections. These would combine climate data from different sources to create a visual, dynamic representation of the information that was both an accurate piece of science and a work of art. They tested their idea with some experimental artworks using data from the Southern Ocean and the Antarctic Circulating Current (ACC), and Southern Ocean Studies was born. Corby explains their choice of dataset. ‘The ACC is hugely important, the strongest ocean current on the planet. It bridges the Atlantic, Pacific and Indian Oceans so it regulates the ecological balance of the whole of the Earth, not just the Antarctic. Climate change is driving up temperatures in the Southern Ocean, so while the ACC buffers Antarctica’s ice sheets from warm water it also carries those rising temperatures around

the planet, with knock-on effects for global temperatures, weather and ecosystems.’ Cunningham and Tancell provided a mixture of live and archived data and models of the ACC, which Corby’s team used to determine the character of the artworks. The result was a series of projections, of ever-changing, circulating patterns of data, carried around the Antarctic continent on a virtual ACC. The project software generates the projections on the fly from layers of background data of ocean temperature, salinity and density, together with tides, sea level and depth, and ocean-current

Real-time data could be the latest weather readings from meteorological stations or information transmitted from loggers on migrating albatross. Viewers could immediately see its effect through the evolving patterns in the projection, without needing to understand how the model itself worked. The ultimate ‘seed’, though, would be the viewers themselves. A further planned installation, the floor projection Coriolis Drift, introduces the human element in a dramatic way by feeding information about the audience back into the model and projecting the effects. Coriolis Drift will use a tracker to detect

THE INTEGRITY OF THE DATA IS CRUCIAL – IT’S ALL GENUINE STUFF.

speeds. These are combined with other environmental and ecological datasets, for example wind speed and direction and biotic information. The viewer sees flickering constellations of tidal flow, winds and organisms. This background could be ‘seeded’ with real-time data which would change the way the projection behaved, in the same way that feeding variables into a climate model would change its output.

how many people are standing on the projection, and where. This information triggers ‘tipping points’ that bring different datasets to the fore – ocean temperature, for example, or krill movements –demonstrating the knock-on effect of small changes on the whole earth system. Just by being there, the audience becomes an agent of change. It’s a striking metaphor for people’s impact on the environment. At each step in the project Cunningham

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Collage produced from multiple data outputs from Envisat radar imagery showing the distribution and extent of sea ice in the Southern Ocean.

has ensured the presentations did not change the data in any way, so the installations were as scientific as they were artistic. ‘The integrity of the data is crucial’, says Cunningham. ‘It’s all genuine stuff.’ It’s also an eloquent way of expressing complex information. Viewers don’t need to understand the data to have a reaction to it. Whether or not you find them aesthetically pleasing, the projections are striking and the data are real, so people can make an artistic or a scientific interpretation, or simply enjoy the view. Cunningham exudes enthusiasm for the project, but he got a mixed reaction from his colleagues at BAS. ‘There were some raised eyebrows,’ says Cunningham, ‘but the whole point is to make people think. Most people were supportive in the end but some felt uncomfortable about devoting too much time to it. When you have such a genuine collaboration between different disciplines you do take a risk; in hard times this kind of thing is the first to go.’ For Cunningham, though, it didn’t feel like that strange a step. ‘It’s no different from the way we’d approach other work we do,’ he explains. ‘You want to work with people who have the right expertise – in this case the right expertise is just in a different area.’ On the back of Southern Ocean Studies, Cunningham and Corby secured funding from the Arts and Humanities Research Council in 2011 and Arts Council England to coordinate the Data Landscapes project.

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Digital artists, scientists, academics, and public and private institutions formed a network to further explore how climate data could be used in creative processes and as a medium for communication in their own right. The projects have demonstrated the benefits of breaking down traditional barriers between art and science, not just to those two communities but to the tax-paying public. The collaborators have developed an effective way to overcome what can be a significant barrier to public understanding of environmental change – the complexity of both the science and the scientific process – by presenting both as an aesthetic experience. The artworks are accessible to people in ways that some other science communications channels by nature cannot achieve. They don’t use the scientific jargon that excludes many readers from academic journals, for example; and unlike media news stories they are not filtered by others’ interpretations. Viewers can experience the complexity of the science in a way that doesn’t require any interpretation at all. One researcher in particular is convinced of the value of this approach: ‘I really believe that, as a scientist, I’ll find better ways of communicating complex ideas by working with the artistic community,’ says Cunningham. As for Southern Ocean Studies, after exhibitions in London and Istanbul which had positive responses from the public

and scientists alike, the next step is a large-scale installation later in 2012, at the University of Westminster’s Ambika P3 gallery. This vast exhibition hall will provide the backdrop for an interactive floor projection up to 50m across, made available concurrently to virtual visitors through social media. In the longer term, Cunningham and the group hope to develop the project to include social as well as environmental science. In the meantime, interacting with data on such a large scale at P3 will give visitors an even more powerful sense of the complexity of the environmental change we are all part of. n

MORE INFORMATION Tom Corby is deputy director of CREAM, the Centre for Research and Education in Arts and Media, at the University of Westminster. Nathan Cunningham was until recently head of BAS’s Polar Data Centre. Email: njcu.home@gmail.com Gavin Baily is director of TraceMedia. www.tracemedia.co.uk Dr Jonathan Mackenzie is a computer scientist and freelance developer. Southern Ocean Studies www.reconnoitre.net/bas/index Data Landscapes project http://data-ecologies.ning.com/page/aboutthe-project P3 exhibition dates, when available: www.p3exhibitions.com


FEATURE

Tackling seafood fraud: fisheries forensics

Media attention to mislabelled seafood is helping bring the scale of illegal and unregulated fishing to consumers’ attention. Gary Carvalho and Stefano Mariani explain how genetic tools can promote sustainability and make sure the fish we buy is what it says on the label.

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ardly a day goes by without more media coverage of the fragile state of our fisheries, or exhortations from TV chefs to give up highstreet favourites like highly threatened Atlantic cod in favour of more sustainable dab or pollock. Such high-profile attention is not misplaced; recent estimates indicated around 88 per cent of fish stocks in European waters were overexploited last year. Globally the situation is no better; over the last 50 years, 366 out of 1519 world fisheries have collapsed – nearly one in four. Estimating sustainable rates of fishing is notoriously difficult, partly because natural fluctuations in many fish populations make it difficult to estimate the numbers needed to replace those that are caught. The situation is made worse by an alarming level of so-called IUU fishing (illegal, unreported and unregulated), which is not included in stock assessment. The global value of legal fishing is estimated at €55–60 billion. The estimated global value of IUU activities is €10–20 billion. Before 2010 (when new regulations were introduced), €1.1 billion of that illegal fish was imported into the EU every year. IUU fishing remains the biggest global threat to the sustainable management of fish stocks, and it’s not restricted to remote areas with limited governance; estimates from the first decade of this century revealed IUU tuna and swordfish in the Mediterranean was 40–50 per cent, North Sea cod up to 50 per cent, and sharks across European waters up to 75 per cent.

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FEATURE

IUU FISHING REMAINS THE BIGGEST GLOBAL THREAT TO THE SUSTAINABLE MANAGEMENT OF FISH STOCKS.

How do we know what fish we’re eating? While protein from land animals comes almost entirely from a handful of artificially selected species (cattle, sheep, pigs, chickens) over which humans have exerted complete control for millennia, protein from the oceans is still harvested from large wild populations, comprising hundreds of species whose biology we don’t yet fully understand. Public knowledge even of emblematic species like Atlantic cod – a mainstay of European and American food culture for over 500 years – is surprisingly poor. In a recent survey less than one person in three was able to identify a cod when shown a photograph of a freshly caught specimen – never mind less popular fish species! Part of the problem stems from the fact that, in many countries, fish is marketed in such a processed state it’s hard to know what you’re looking at. Together with overexploitation, this practice has created the ideal conditions for product substitution, whereby less valuable, and often more readily available, species are mislabelled as more sought-after ones. Such activity causes serious harm at many levels: fraudulent

Gary Carvalho (middle) and colleague, Martin Taylor (left) from Bangor University, with fisheries officer Abdul Rahman, sampling fish in Malaysia for genetic analyses.

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seafood industry operators make huge profits; consumers won’t understand the diversity of natural food resources nor how threatened some of them are; and some people might unknowingly be exposed to the risk of food allergies when they buy mislabelled products. All this is a significant threat to consumer trust and to the livelihoods of diligent fishindustry operators who do the right thing. What we urgently need is a framework to promote compliance with regulations, and the political will and mechanisms to enforce those regulations, through prosecution where necessary. Tackling seafood mislabelling and IUU activities Relatively strict EU legislation on labelling and traceability has existed since 2000, and a new regulation to stop imports of IUU fish products into the Community came into force in January 2010. The problem is that traditional certification is vulnerable to fraud, especially since fish are processed at sea and many of the features that distinguish different species are removed. What regulators need is an independent forensic test that will work equally well from the moment they are caught to when they are served up on our plates, to identify whether they have been caught illegally, or to check whether a product in a supermarket or restaurant is what the label says. The only reliable approach is to use DNA-based technologies, and that’s where our work comes in. DNA tests are sensitive enough to distinguish species and even populations, quick enough to be costeffective, and reliable enough to provide robust forensic validation and evidence in a court of law. The illegal substitution of one species for another is best tackled by a method known as ‘COI barcoding’, a process that works by analysing the 600 base-pair sequence of the mitochondrial DNA cytochrome c oxidase I gene. DNA results from fish samples can be matched against the Barcode of Life Data system (www.boldsystems.org) which currently contains the DNA sequences of nearly a third of known fish species. The method is cost-effective and reliable. Virtually any product advertised or sold as a particular species, anywhere in the world, can be verified unequivocally using a COI barcoding test. But this doesn’t give us enough information to identify biological populations or regional stocks within a species, which is crucial if we want to know when a threatened or lower quality fish is being substituted for another of the same species. For this we need to look at an


Dana D. Miller

Bewildering species diversity in mixed trawl of fish from Malaysian waters collected for genetic analysis – you won’t spot any cod in here!

emerging class of genetic markers called SNPs (single nucleotide polymorphisms). These represent novel genetic differences in the DNA sequence, known as ‘point mutations’. The frequencies of each SNP variant are different for (and so can be used to distinguish between) different regions or populations, because interbreeding fish that share a common spawning ground are isolated to varying degrees from other groups, allowing independent changes in SNP frequencies – a ‘population signature’. SNPs are abundant and widespread across every genome and are highly informative for

Martin Taylor

Family members – five species typical of British and Irish waters, from top to bottom: cod, saithe, pollack, haddock, whiting. DNA barcoding has shown that the latter four may often be sold labelled as cod.

understanding the fundamental biology and conservation needs of different species, and ideally suited for traceability purposes. Importantly, data from SNPs are especially good for creating a reference database, because they are easily reproduced among different laboratories; newly collected data can then easily be compared with reference data. Another benefit is that SNPs vary due to both demographic and environmental factors – that is, they vary because of migration and population isolation, and also because of adaptive changes in the genome through natural selection, as groups of fish adapt to specific local environments. This greatly improves the power to detect the distinct signatures of local and regional groupings. Fish fingerprinting in practice A flurry of COI barcoding studies over the last five years has revealed astounding levels of fish mislabelling in at least three continents, affecting major seafood species including cod, hake, red snapper, haddock and tuna. In most cases, cheaper and more plentiful species were being substituted for more sought-after produce; whereas in some cases, endangered and protected species were labelled under deceptively generic names. Most recently, Atlantic cod (Gadus morhua) has been discovered marketed as the related, but less threatened, Pacific cod (Gadus macrocephalus). This kind of substitution is particularly detrimental to environmentally aware consumers, who rightly expect ‘eco-labelling’ will help them avoid species or stocks that are under severe pressure. A European consortium, FishPopTrace,

recently used SNPs for the first time to trace fish and fish products back to their population of origin. They developed a ‘SNP chip’ for each of four species: sole, hake, cod and herring. These devices contain chemicals that recognise only those SNP markers specific to a species or population. DNA samples taken from the fish are exposed to the SNP chip in the lab, where the relative frequencies of each SNP are revealed. These devices enabled researchers to test the identity of 1536 possible SNPs for each population. The result was a series of diagnostic patterns of SNP frequencies – the population signatures we mentioned earlier. This provides a baseline against which we can compare fish of unknown origin. One application of SNPs has been to distinguish between different types of the same cod species. Cod from the Baltic are worth less than Atlantic cod because they tend to have lower quality flesh and more contaminants. Having established a reference database, researchers looked at 20 SNPs and identified the origin of every fish from a sample collected from both regions. Even with just 10 SNPs, 96 per cent of the unknown samples were still correctly identified. In another case, FishPopTrace distinguished between North Sea sole (Solea solea) and its more highly prized Mediterranean counterpart with similar accuracy – using just one SNP. SNP markers are so reliable that they have direct applications for control and enforcement authorities, and ultimately for the confidence of those of us who like to know where our fish dish has come from. They should become the standard tool for identifying source populations, and for verifying the origin of landed fish and processed fish products. SNPs can provide the technology for fish traders, processors and retailers to self-certify, for governments to enforce regulations, and give law courts access to unambiguous scientific evidence. If coordinated action is taken at national and transnational levels, the seafood industry has a fresh opportunity to operate in a more transparent way, letting us trace our fish ‘from ocean to fork’, with the many benefits for the environment and the consumer that this will bring. n

MORE INFORMATION Gary Carvalho is Professor of Molecular Ecology at Bangor University. Email: g.r.carvalho@bangor.ac.uk Stefano Mariani is Reader in Wildlife Biology at the University of Salford. Email: s.mariani@salford.ac.uk

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FEATURE

Visions of sustainability This year NERC co-hosted a major conference, Planet Under Pressure, which brought together more than 3000 delegates from around the world to discuss the big environmental issues facing our planet. Three sessions in particular called for a new approach. Bridging the worlds of science, the arts, politics, business, faith and the global South, the BRAVE collaboration challenged participants within and beyond the conference to develop a shared global vision of sustainability and come up with some big ideas for achieving it. NERC is one of six partners in the BRAVE collaboration – Big Radical Approaches towards

a Vision for the Earth. In the first of three debates chaired by the BBC’s Quentin Cooper, BRAVE presented interviews with people at the sharp end of unsustainable development. They were asked for their visions of a sustainable world. Responses to the film were recorded at the conference to be sent to the interviewees, the local film-makers and their communities, to begin a dialogue about the issues they had raised. This short selection of quotes, abridged from the interviews, gives a flavour of the passion and responsibility felt by people whose voices are not often heard.

Liyu, member of the Ethiopian National Youth Coalition on Climate Change and a British Council climate champion

Tatek Kebede, national coordinator, Ethiopian National Youth Coalition on Climate Change, Addis Ababa

Iasaid Khonjee, teacher in Cherapunjee, India, and president of a local NGO giving support to the indigenous Khasi population

It is the responsibility of me and everyone to think of the future children. If everyone is taking their own responsibilities it will bring the solution for everybody. Everyone should take an action at this moment of time so that there will be a green hope in the future and a positive hope for tomorrow. In our places people are not even aware of what climate change means. I’m creating awareness so that people will know what is happening, so that they will take action. I have a message to tell to everyone: whenever we do something for ourselves, think of others which would be affected by your actions. That’s my message. Whenever we are getting richer and richer, the poor are getting poorer and poorer.

The very concept of sustainability has inherent complexity. It says you have to feed the current generation without compromising the needs of the coming generation: how? Within an already unjust system, how could you ask people to care for the coming generation when they are living dehumanized, less than what their human dignity requires? I have a message for the rest of the world, especially for those living in the West, the North, those with good living standards; to make our world a better place for all of us they must also stand in solidarity with the poor without any kind of discrimination. So if you have the skills, please share it; if you have the knowledge please, again, share it; if you have the resources, of course please share it.

Nowadays we talk so much – start something! Do something concrete. We, the Khasis, have a very strong point from where we can start, our culture is progressive. We do not say what comes from the other parts of the world is bad; no, we look into our own self. Our forefathers gave respect to all the existence of nature – every atom of their being is involved in the earth. Can we the Khasis look back into our own history? Have the courage? Can we afford to be honest, eat honest beef, eat honest pork? These are the things that will give answer to many, many problems. The trees, they grow in their own way. The birds go their own way from the beginning of the universe. The rivers, they keep on flowing, they follow their own way. We humans, we never follow our own ways.

NOWADAYS WE TALK SO MUCH – START SOMETHING! DO SOMETHING CONCRETE. 22

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IT IS NOT US IN THE OFFICES, US IN THE UNIVERSITIES, WHO WILL BRING CHANGE.

Bibiana Ranee, farmer and community leader, Nongtraw, India

Lubna Seal, researcher in Dhaka, Bangladesh, and a British Council climate champion

The people do not understand much about the value of food, about the food we grow in our own places. According to me, we should try to be independent of food coming from other states. My personal attempt is to help others understand – the women, the youth, the young ladies. For this reason I try to clean my surroundings and not cut the trees in the compound. We strive to conserve the trees around us and conserve the richness of the soil which comes from these trees themselves. Especially in this generation people cut ten trees but never produce even a single tree. This is the news I want to give to others: that if they cut one tree they should plant ten new trees.

More funds are allocated for issues like climate change adaptation, climate change mitigation or green technology, but we hardly focus on the population-growth issue. Population control should be the prior goal to start any kind of development activity. If you have a small number of family you can give them proper education, proper food, proper health, everything. But the problem is that most of the illiterate people and people who are living in the rural areas or the very hard to reach, they don’t have the knowledge that they should maintain a small family. So first comes population control, then you control your consumption, then you can lessen the dependency on resources and you will generate less waste.

Dudu Khumalo, community activist, Mzinyath, Durban, South Africa

Wansalan Passam, project coordinator at Meghalaya Rural Development Society, India

People are chasing after wealth instead of having just enough. As human beings we depend to a great extent on something which life offers freely, like mutual support, affection, generosity – I think that is something we should pay attention to.

We have to unite so that we can save our planet. The obstacles are the money, and the capitalism. The capitalists become very greedy, they want to put money in their own pockets, they don’t want to put money where the money is needed. We are not saying give the money to the people – but give the good quality service to the people. If you have had a chance of being educated and have more skills, you have to use that to educate other people as well. Those who have more must share something with those other people. And if we don’t share the resources of this world we are not going anywhere.

Tichafa Makovere Shumba, Zimbabwean permaculture trainer, living in Ethiopia

I believe in the principles of permaculture where we share surplus – surplus knowledge that helps us to care for the people, that also helps us to care for the land. This should be quite free to anybody. We don’t need to spoon feed the people, we don’t need to bring gifts to the people. My belief is that care for the people is actually teaching them how to produce their own food; they should be taught how to make their living comfortable by themselves. We have conferences, yes, but do we really involve community leaders? There are people who are really respected by the grassroots people; these are the people who can help us take action. It is not us in the offices, us in the universities, who will bring change. Bah Priak Riahtam, teacher and secretary of an NGO for the development of the Khasi people in Meghalaya, India

My view of the world as it should be, it should be the green, young, energetic Mother Earth. When we talk of the world it is not the world of one or two individuals but it is a wide and a vast world. It does not mean that in only our place we should make the hills green. In this mission, all must be involved.

MORE INFORMATION BRAVE collaboration partners are: UK Collaborative on Development Sciences, NERC, InsightShare, Arts and Humanities Research Council, British Council and CAFOD. The main film and some of the interviews are available on BRAVE collaboration’s website http://bravecollaboration.tumblr.com

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FEATURE

Bogged down in history

Britain was a major source of tin in the ancient world but details of how this important commodity was exploited were sketchy at best – until Andy Meharg and colleagues Kevin Edwards and Ed Schofield got stuck into two West Country peat bogs.

T

tbradford/istockphoto.com

in has played an important role in the development of human society. Either on its own or mixed with copper to form bronze, it had a place in everything from coins and jewellery to armour and weapons. But unlike copper, tin deposits are extremely rare, and ancient Mediterranean cultures (from the Bronze Age through to Roman times) had to look to the remote Atlantic fringes of Europe for their closest supplies. South-west Britain was home to the largest European tin deposits, and this mineral wealth must have been a significant source of economic and cultural contact between Britain and mainland Europe. But there is not much evidence, archaeological or historical, for how the tin trade developed. Around 440BC, the Greek historian Herodotus wrote about tin sources in the ancient world: ‘I cannot speak with certainty, however, about the marginal regions which lie toward the west, in Europe... Nor am I certain of the existence of the Cassiterides Islands, from which we get our tin.’ Pytheas of Massalia (modern Marseilles), who is credited with being the first person to circumnavigate Britain around 300BC, also talked of a tin-bearing island named Mictus within six days’ sail of Britain. Cornwall, particularly St Michael’s Mount, has long been associated with the ‘tin islands’ – the Cassiterides – to which Herodotus referred, but it’s not much to go on. In an attempt to add to the body of evidence, myself and colleagues at the University of Aberdeen looked to the peat bogs of the south-west. These bogs have been soaking up atmospheric pollution for centuries and we hoped that pollution would include traces of tin released into the atmosphere from mining and tinworking. The sites we chose – Tor Royal on Dartmoor and Dozmary Pool on Bodmin Moor – are themselves better known as the location for Sherlock Holmes’ encounter with the Hound of the Baskervilles, and the place where King Arthur deposited Excalibur, respectively. More pertinent to our study, though, is that both lie undisturbed in the middle of an ancient tin-mining region, and both are ombrotrophic – they get all their water from rainfall rather than from springs or streams. This is important because it means any minerals they contain must have been deposited from the atmosphere rather than carried from surrounding rocks or soils. Our approach was based on the fact that minute particles of tin are released when ore is crushed and smelted, and these eventually fall back to the ground or are washed out of the atmosphere by rain. Assuming these particles had accumulated and lain undisturbed in the bogs, analysing the amount of tin at different depths would give us a sequence of tin exploitation, with greater concentrations

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Peat coring at Tor Royal on Dartmoor.

An extracted peat core.

representing periods of more intense mining and smelting. And because the bogs are made up of organic material, we could radiocarbon date the layers associated with different phases of tin deposition to find out when they had occurred. Our specialised equipment enabled us to core 4m down through the peat, so we were able to work out a chronology of tin deposition and, by analogy, of tin mining and smelting, going back thousands of years. This chronology adds so much detail to what we know about this period that it will allow us to rewrite the story of ancient Britain’s trade links with Europe. Analysis of the Himmelsscheibe, a bronze disk found near Leipzig, Germany, which is inlayed with a gold map of the heavens and dates to around 1600BC, indicates that it contains tin ores from southwest Britain. So British tin was undoubtedly traded to some extent during the Bronze Age, but our findings suggest that production was low. The cores showed that, at most, there was only sporadic atmospheric deposition of tin into the peat during the Bronze Age, between around 2500 and 800BC, and this pattern continued until early Roman colonisation, around AD100. This confirms what we had already gleaned from archaeological and fragmentary documentary evidence; that there may have been only limited tin mining and bronze production in south-west Britain over this period. But what of the Roman period? Until now many archaeologists believed the Romans did not exploit British tin until the 3rd century AD, when they had exhausted more accessible Spanish supplies. Our cores tell a different story. They show sustained and substantial tin exploitation from around AD100 onwards. We don’t know if it was the locals or the Romans who were responsible, but as this activity was in the heart of a region considered to have been on the very margins of Roman colonisation, these findings hint that the Romans’ economic and social reach in this relatively isolated region was earlier and more extensive than we thought.

Another indication that our miners were part of the Roman economy is that deposition in the peat stops around AD400, when the Romans left, and for the next three centuries the cores show little activity. But then follows perhaps the most remarkable part of our story. Beginning in the 7th century AD the chemical record shows extensive tinworking all the way through to the time of the Norman invasion some four centuries later. This supports what the scant archaeological evidence from this period suggests that Britain was more than likely the only source of European tin by this time, and it was turning up in bronze church bells, pewter, jewellery and armour – most famously on the tinned silver finish of the bronze helmets from the Anglo-Saxon burials at Sutton

Hoo in Suffolk. Our findings imply that tin mining and trading was highly organised in early medieval Britain and, together with finds like Sutton Hoo and the Staffordshire gold hoard discovered in 2009, this suggests that ‘Dark Age’ society was technologically richer and more organised than many people assume. As we hoped, coring through the centuries-old, undisturbed peat revealed a unique record of atmospheric pollution deposition from ancient times. Reading these cores in the right way can yield rich information about past human activity where written records are absent or confused, and where archaeological evidence is missing or poor. This can let us address ancient myths and, as here, shed new light on the history of Britain and its place in Europe. n

MORE INFORMATION Professor Andy Meharg is Chair of Biogeochemistry at the Institute of Biology and Environmental Science, University of Aberdeen Email: a.meharg@abdn.ac.uk. Professor Kevin J Edwards and Dr J Edward Schofield are both in the Department of Geography and Environment at the University of Aberdeen.

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FEATURE

Understanding the sediments deposited by devastating tsunamis is essential for identifying where similar disasters have struck, how big they were and how often they can happen. Ultimately this could save lives. Hannah Evans and colleagues from the British Geological Survey (BGS) describe their journey to Japan to aid international scientists in the aftermath of last year’s tsunami.

Waiting for the next big I

n March 2011, the magnitude 9 Tohuku earthquake caused a massive tsunami to hit the east coast of Japan. Despite sophisticated warning systems and coastal defences, at the most recent count 15,000 people are known to be dead, nearly 5000 are still missing and 300,000 were left homeless. We visited Japan just three months after the tsunami to help investigate the sediments the tsunami left behind, to map the areas flooded and to record evidence for the height of the waves. By comparing the results of our research with evidence from the geological record – the sediments buried beneath the modern land surface – we can improve our understanding of the size of past tsunamis and the timescales on which they occur. This will help create better evacuation procedures and coastal defence measures, and aid redevelopment of the area, potentially reducing loss of life from future tsunamis. Mapping a modern tsunami The 2011 tsunami gave us a unique opportunity to investigate deposits from a known catastrophic tsunami and to build up a picture of the type of sediments that

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these waves leave behind. An area affected by a modern tsunami is a difficult working environment and the east coast of Japan was no exception. The sheer scale of the devastation that the tsunami caused was unbelievable. A postapocalyptic landscape is perhaps the best way to describe the scene that greeted us on reaching the tsunami zone. Not only was a huge swath of the Japanese coast affected – some 500km of the eastern shore of Honshu Island – but huge piles of debris, including buildings and lorries, were left strewn across the area. Trees were stripped or bent double and concrete blocks some 10m long were thrown inland from the destroyed tsunami defences at the coast. All manner of personal possessions were scattered everywhere as a tragic reminder of the impact on local people. To gain a better understanding of the extent and characteristics of the tsunami sediments we used a combination of high-resolution satellite images and digital mapping techniques. Our results reveal that the tsunami waves travelled up to 4.5km inland on the low-lying coastal plains. We recorded evidence of the height of the waves

as they flowed over the land. This included trees with their branches stripped to around 7m above ground level and debris stranded on three-storey buildings. In highland regions further north, narrow coastal valleys focused the tsunami waves leading to water heights of up to 40m. This was responsible for the almost total destruction of several towns along the coast, including the town of Minamisanriku. Our mapping demonstrates that sediments from the 2011 Japan tsunami are up to 30cm thick and are largely composed of fine sand and silt eroded from areas just offshore and near the coast. The tsunami also deposited bigger man-made items like houses and cars. Tsunamis in the geological record Historical records such as written archives and local folklore are often used to give scientists an idea of how often tsunamis have affected an area. Such records may contain information on small to medium height waves but aren’t likely to include the largest events – these happen so rarely that the last one may have struck an area long before records began. To understand the biggest and most devastating tsunamis we must turn


Mapping the tsunami sediments.

wave to the geological record. Mapping recent tsunami sediments, such as those from the March 2011 tsunami, is vital if we are to learn to identify tsunami deposits in the geological record. Once we have recognised similar sediments from the ground beneath the modern land surface, we can date them, and combine these dates with those from historical records to build up a picture of tsunami size and frequency. The geological record in Japan stretches back some 3800 years. Within these sediments, evidence has been found for a number of tsunamis. The largest of these occurred in 869AD and is known as the ‘Jogan Tsunami’. The sand it deposited extends several kilometres inland and this has been used to estimate the size of the waves. However, our investigation of the March 2011 tsunami revealed that finer deposits laid down by the tsunamis, known as silt, may extend much further inland than the tsunami sand. The Jogan tsunami is likely to have deposited silt but this is very fragile, and so is easily destroyed by wind and rain and the activity of humans. This means that any silt from the Jogan tsunami may well have been eroded over the 1143 years since it happened. So the Jogan tsunami was probably much bigger than previously believed, with the tsunami waves affecting a larger area of land. To cause such a big wave, a large earthquake is needed. The earthquake that triggered the Jogan

tsunami may therefore have been as large as that of March 2011. This would mean these devastating events could happen more often than previously believed. Research into the geological record in countries prone to tsunamis is, therefore, very important in identifying the size of past tsunamis and how often they hit an area. Our work is part of extensive research being conducted on last year’s disaster in Japan to improve our understanding of tsunami size and frequency. Our ultimate aim is to reduce the loss of life from future events by allowing improved tsunami warning systems, evacuation procedures and coastal defence measures. n

MORE INFORMATION Hannah Evans is a coastal and geohazard geomorphologist at BGS. Professor David Tappin is a BGS tsunami researcher. Dr Colm Jordan is a remote sensing geologist and team leader for the BGS Earth and Planetary Observation and Monitoring Team. Email: hann@bgs.ac.uk. This work was funded by the Japan Tsunami Urgency Response NERC Urgency Grant. www.bgs.ac.uk

The remains of the town of Minamisanriku.

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PODCAST Q&A

Revitalising urban rivers

The River Wandle in Carshalton, south-west London, is like many urban rivers. A couple of hundred years ago it flowed through rural fields but today it’s flanked by roads, railways and buildings and has been diverted and polluted by urban development. At one stage in the 1960s the Wandle was in such a bad state it was effectively an open sewer. But all is not lost. Richard Hollingham met Angela Gurnell from Queen Mary University of London, Dave Webb from the Environment Agency and Bella Davies from the Wandle Trust to find out how scientific research is helping revitalise even the most neglected rivers.

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THIRTY YEARS AGO, THE IDEA THAT YOU’D SEE TROUT IN GREATER LONDON, OR KINGFISHERS IN WANDSWORTH AND LEWISHAM, WAS RIDICULOUS. BUT NOW IT’S QUITE COMMON.

Richard: Just to set the scene, we’re beside a busy road almost beneath the arches of a railway track, and the river itself – well, there’s not a great deal to it, it’s more a wide stream. What has this river been subjected to over the last few centuries?

Bella: A couple of hundred years ago this area was much more rural. Even then, though, the Wandle was used by lots of mills – it’s actually known as one of the hardest-worked rivers in the world for its size. Then the Industrial Revolution created an awful lot of pollution and there was a general disregard for rivers across the country. By the 1960s, the Wandle was an open sewer and more or less biologically dead. During the 1970s, it was canalised and straightened to help with flood defences. Now we’re trying to restore many of its natural processes and habitats.

Richard: Angela, your research has been the basis of this restoration work.

Angela: My job has been to find ways to measure various properties of these rivers and use that to understand which sections are good and which are bad – largely in terms of their aesthetics. If you combine that with information on water quality you can start to understand what the effect might be on organisms, particularly the animals that live in the river. Originally we wanted to understand how engineering, for flood defences or development, had affected the character of urban rivers. Clearly the highest quality rivers will be those that have space to adjust and where engineers haven’t straightened or reinforced them and so on. But when we compared the properties of the engineered and natural stretches of river we were surprised to find that certain types of engineering – particularly bits that are patchy and varied – are compatible with a varied and attractive river. And if the water quality is good they can support diverse ecosystems too.

Richard: So all is not lost, even if a river is surrounded by urban concrete?

Angela: That’s right. Clearly it’s easier to work on areas where you have the space to do more or less what you like. But you can still do quite a lot to improve sections like this, where we’re standing now. Gently pushing away at the engineering and removing the bits that you actually don’t need allows the river to recover in a patchy way.

organisms, so we knocked part of it out to channel the water through a smaller space, which is why it’s flowing faster. We added around 60 tons of gravel in this area and sculpted it to create a range of different habitats. We’ve also narrowed the river upstream and put in new banks and over a thousand native plants. We’re particularly excited that the gravel has provided spawning beds for wild brown trout – in fact they have spawned in this very section. A lot of this work was done by local volunteers – they’ve really been at the heart of the project and now this is their patch to look out for. Lots of other local people – anglers or people interested in wildlife and fish – are really supportive too.

Richard: Can this be done in other rivers?

Dave: Absolutely. In some respects, the Wandle is typical of many London rivers. Thirty years ago, poor water quality was the main influence on river ecology – even people were encouraged to keep away. But now that water quality has improved, habitats are more significant in determining what lives in the river. The last few decades have seen habitat destroyed and fragmented, so we need to restore channels in open spaces and remove blockages so animals and plants can move from one good bit of habitat to another. Removing things like the weir reconnects the river and makes it more resilient to pressures like extreme flooding or even pollution, because animals can move freely along the river and colonise new areas if their previous habitats are damaged. We’ve been helping many local groups to set up river restoration projects across London.

Richard: And as if to prove everything we’ve been talking about, you say you saw a kingfisher here?

Dave: I did – it’s not that uncommon to see kingfishers on our urban rivers. Thirty years ago, the idea that you’d see trout in Greater London, or kingfishers in Wandsworth and Lewisham, was ridiculous. But now it’s quite common. We now know that we need to manage rivers in an integrated way. So the idea that you only manage a river for flood defence or for moving waste water from A to B has gone. The aim now is to do all those things in a way that maintains the vitality of the life in the river too.

Richard:

Bart Broek/istockphoto.com

Let’s talk about what you’ve done here. The river is quite fast flowing and then it disappears under the railway bridge and, apart from the road on one side, you could be in the countryside.

MORE INFORMATION

Bella:

http://planetearth.nerc.ac.uk/multimedia/story.aspx?id=1145

Yes, it just shows what you can achieve. At this particular site the river used to be too wide and a weir was put in to hold the water back. The weir was an impassable barrier to fish and lots of other

For more information about the restoration of the Wandle visit

This Q&A is adapted from the Planet Earth Podcast, 31 January 2012. The full podcast and transcript are on Planet Earth Online:

www.wandletrust.org

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Planet Earth Summer 2012