www.planetearth.nerc.ac.uk
Winter 2012
Slime Explaining climate powerextremes Bioenergy from the sea
Also:corals Lake Baikal, Pearlgeology mussels, Valuing• nature Cold • Local survey Antarctic recollections
•
Copaíba oil
About us 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
Contact us To give us your feedback or to subscribe email: requests@nerc.ac.uk or write to us at Planet Earth Editors, NERC, Polaris House, North Star Avenue, Swindon SN2 1EU. NERC-funded researchers should contact: editors@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.
Editors Adele Rackley, 01793 411604 admp@nerc.ac.uk Tom Marshall, 01793 442593 thrs@nerc.ac.uk Science writer Tamera Jones, 01793 411561 tane@nerc.ac.uk Design and production Candy Sorrell, 01793 411518 cmso@nerc.ac.uk ISSN: 1479-2605
Front cover: Courtesy The Scottish Association for Marine Science
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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.
In this issue Winter 2012
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18
10 A GLIMPSE of
Greenland’s future
Predicting the fate of Arctic ice sheets.
12 No stone unturned
Finding the right rocks to keep historic buildings in good nick.
16 Blinded by the light
How do street lights affect bats?
18 Cold corals in hot water
How will cold-water reefs cope with environmental change?
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20 You heard it here first
26 Can money grow on trees?
24 Can butterflies keep cool in
28 Whales, worms and the
An unofficial history of Britain in Antarctica.
a warming world?
Moving to cooler areas may not be enough.
Medicinal oil – a new livelihood for people in the Amazon?
story of life
On the benefits of recondite research.
25 Ocean acidification – no
30 Slime power – bioenergy
enemy to anemones
Research shows some marine life could thrive in a high-CO2 world.
from the sea
How marine algae could help solve our energy problems.
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News Editorial B
y the time this issue of Planet Earth is with you, autumn will be over and summer a distant memory. But we’ve rustled up a selection of stories we hope will help fill the long winter evenings. Laurence Dyke describes his group’s understanding of how the Arctic ice cap will respond to climate change. And Laura Wicks, on the one hand, and Dave Suggett and Jason Hall-Spencer on the other, tell you about the different approaches they’re taking to finding out how ocean acidification will affect coral reefs, some of the most diverse habitats on Earth. Elsewhere, we learn how seaweed could help solve our energy problems and how butterflies might fare in a warmer world. Climate change, energy security, maintaining biodiversity – these are major challenges and addressing them is essential to our long-term wellbeing. But environmental science isn’t just about understanding and tackling the great environmental problems of the day; it can make people’s lives better in a multitude of different ways, many far from obvious. Peter Newton tells us how drilling trees for medicinal oil could let people in the Amazon earn extra income that could transform their families’ prospects. We find out how English Heritage is working with the British Geological Survey to keep the nation’s historic buildings in good condition. And Nick Higgs tells us about the important benefits that spring from his study of the worms feeding on dead whales – from filling the gaps in our understanding of evolution to helping forensic investigators work out how long human bodies have been in the water, or even just filling us with wonder at the miracles of nature. Finally, have you ever wondered how to go about transporting a husky team in a light aircraft or finding your way back to the tent in a polar blizzard? Learn all this and much more in our selection from the oral archive of the British Antarctic Survey.
The Editors
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Insight into venom evolution could aid drug discovery
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recent discovery about snake venom could lead to new drugs for life-threatening conditions like cancer, diabetes and high blood pressure. Most venom contains a huge variety of deadly toxin molecules, evolved from harmless compounds that once did other jobs elsewhere in the body. These disrupt normal processes in snakes’ prey, such as blood clotting or nerve-cell signalling. Now researchers have discovered that deadly toxins can evolve back into harmless molecules, raising the possibility that they could be developed into drugs. ‘Our results demonstrate that the evolution of venoms is a really complex process. The venom gland of snakes appears to be a melting pot for evolving new functions for molecules, some of which are retained in venom for killing prey, while others go on to serve new functions in other tissues in the body,’ says Dr Nicholas Casewell, who did the research at Liverpool School of Tropical Medicine and is now at Bangor University. Scientists have long seen toxins as useful targets for drug development, because they target metabolic processes. But drug developers have had to modify them to make them safe for human use while retaining their potency. The breakthrough, published in Nature Communications, suggests there could be harmless versions of toxins throughout snakes’ bodies. A whole new era of drug discovery may be dawning.
Daily updated news @ www.planetearth.nerc.ac.uk
Warmer Atlantic blamed for gloomy UK summers
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he UK’s recent run of dismal summers was strongly influenced by a major warming of water in the North Atlantic Ocean which started back in the 1990s and continues today, scientists say. And while it stays warm, the situation is unlikely to improve. ‘You’re not always going to get one, but as long as the Atlantic is warm, the chances of a wet summer are increased,’ says Professor Rowan Sutton, director of Climate Research in NERC’s National Centre for Atmospheric Science (NCAS), who led the study. Last time the Atlantic was this warm, it stayed that way from 1931 until 1960. This led to a run of wet summers over the UK. Lynmouth in Devon experienced disastrous flooding in August 1952, and severe floods in 1948 closed the east coast mainline for three months. The present warm phase only started around 1996, so it might be some time before the ocean cools down again and we see a return to more agreeable summers. But like all things weatherrelated, its duration isn’t easy to predict. ‘We can’t assume the current warming will be as long as the previous one. We just don’t know how long it’ll go on for,’ says Sutton. The results appear in Nature Geoscience. The researchers analysed long-term records of air temperature, rainfall and pressure at sea level for the two warm periods. They compared these records with those from a cool period in between. By comparing the observed changes with computer simulations of the climate system, they found compelling evidence that the Atlantic’s temperature influences all of Europe’s climate. ‘The state of the oceans tells you about weather patterns that are likely to evolve several years ahead,’ says Sutton.
Ocean sediment gives ancient temperature record S cientists have created a more accurate history of how Earth’s climate has varied over the last 1.5 million years, after developing a new method that lets them draw on natural temperature records that have never before been analysed. The new technique improves on earlier ways of reconstructing the ancient climate. These are distorted by measuring both the Earth’s temperature and the amount of its water locked up in glaciers and ice caps. The new method disentangles the two, giving a better view of fluctuations between warm and cold periods. The Science study also sheds new light
on an important turning-point in climate history, known as the Mid-Pleistocene Transition (MPT) – a major shift that took place between 1.25 million and 600,000 years ago, when the planet’s ice ages moved from a 40,000-year cycle to a 100,000-year one due to small, recurrent changes in its orbit around the Sun. ‘Previously we didn’t really know what happened during this transition, or on either side of it,’ explains Professor Harry Elderfield of the University of Cambridge, who led the study. ‘Before you separate the ice volume and temperature signals, you don’t know whether you’re seeing a
climate record in which ice volume changed dramatically, the oceans warmed or cooled substantially, or both.’ The new method works by analysing variations in the ratio of magnesium to calcium in the fossilised shells of microorganisms called foraminifera trapped in successive layers of sediment. As these grew, they absorbed calcium and magnesium in proportions dependent on the water temperature around them. Understanding past changes in the climate should help predict future ones more effectively, including the contribution of human carbon dioxide emissions.
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News Massive methane stores could sit beneath Antarctica
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here could be as much methane beneath Antarctica’s vast ice sheets as there is trapped in the Arctic permafrost, researchers have discovered. If the sheets keep thinning as the climate warms, the Nature study suggests stores of the powerful greenhouse gas could escape to the atmosphere. This would speed up rises in temperature, causing even more methane to be released. The fact that the poles are the fastestwarming regions of the planet could make the problem even worse. So far, researchers have focused on the fate of methane reserves in the northern hemisphere, in places like the Arctic permafrost. But recent research has revealed that the Antarctic ice harbours microbes and carbon left over from ancient marine sediments and other habitats from
People didn’t think there was life beneath Antarctica until around the 1990s. But over the last ten years, researchers have discovered that there are microbes and organic carbon. And it’s remote from the atmosphere, so it’s a perfect place for methane-generating microbes to live. Professor Jemma Wadham, University of Bristol
before the ice sheet grew, 30 million years ago. And low-oxygen conditions beneath the ice mean it could well host microorganisms that generate methane. The research shows these environments are almost certainly biologically active. So organic carbon may have been metabolised by oxygen-deprived microbes, turning it to carbon dioxide and methane over millions of years. The team calculates that half the West Antarctic Ice Sheet and a quarter of the East Antarctic Ice Sheet sit atop ancient sedimentary basins, containing around 21,000 billion tonnes of carbon. ‘This is an immense amount of organic carbon, more than ten times the size of carbon stocks in northern permafrost regions,’ says lead author Professor Jemma Wadham.
Amazonian tree rings reveal past rainfall S
cientists have used rings from just eight trees in Bolivia to get a detailed picture of rainfall patterns across the Amazon basin over the last century. The rings in the lowland tropical cedar trees form a natural archive of data, closely related to historic rainfall. ‘Climate models vary widely in their predictions for the Amazon, and we still do not know whether the Amazon will become wetter or drier in a warmer world,’ says Professor Manuel Gloor from the University of Leeds, co-author of the Proceedings of the National Academy of Sciences report. ‘But we’ve discovered a very powerful tool to look back into the past, which allows us to better understand the magnitude of natural variability of the system.’ Gloor and colleagues measured the ratios of two different forms of oxygen, known as isotopes, trapped in the tree’s annual rings. This told them how much rain fell in the Amazon basin over the last century; rain contains more of the heavier isotope than the lighter. They found that variations in the ratios of the two types of oxygen accurately reflect changes in rainfall, and that the results from just eight trees represent the overall Amazon climate well, agreeing with other records.
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Lead author Dr Roel Brienen taking a core sample from a Bolivian cedar tree.
Daily updated news @ www.planetearth.nerc.ac.uk
David C J White
in brief . . . Zooming through the tree of life A ground-breaking new website called OneZoom provides a new way to visualise the mammalian family tree. It represents evolutionary relationships using fractals; from a distance you see only the main groups, but zooming in reveals ever-greater levels of detail until you reach the level of individual species, with conservation information and IUCN red list status. OneZoom was created by Dr James Rosindell from Imperial College London, who hopes that showing both the big picture of life’s family tree and its intricate detail will let people visualise its subject matter more easily and intuitively than ever before. www.onezoom.org
New funding for water innovation
Man-made marshes poorer in plant-life than natural ones A
rtificial salt marshes are no substitute for natural ones, hosting fewer kinds of plant and often ending up overrun by just a few species, scientists have shown. That’s a problem, because the EU Habitats Directive obliges the UK to replace salt marsh lost to coastal development or erosion with new, ‘biologically equivalent’ habitat elsewhere. Until now we’ve thought we were complying, but the new study shows that creating artificial salt marsh that’s an effective substitute for the real thing is a lot harder than we thought. Researchers examined natural and man-made salt marshes, comparing the range and abundance of plants growing there. What they found was discouraging. Many of the plants common in natural salt marshes were rare or non-existent in artificial ones. These include species like sea lavender, thrift, sea arrowgrass and sea plantain. Instead, man-made marshes – even ones created accidentally in the 19th century – were often dominated by shrubs like sea purslane. ‘Salt marsh formed naturally, so people have assumed that it would be straightforward to create it again – just let the sea back in,’ explains Professor Alastair Grant of the University of East Anglia, co-author of the study, which appears in the Journal of Applied Ecology. ‘We show this isn’t the case; we’re arguably not complying with the Habitats Directive.’ The picture isn’t hopeless, though. Relatively simple measures can help bring new wetlands much closer to natural ones. These include raising valuable plants in nurseries before planting out, and taking care to vary new wetlands’ topography by making gullies, mounds and creeks that create conditions favourable for a variety of plants and prevent the dominance of any one species.
The Technology Strategy Board, Defra, NERC and the Engineering and Physical Sciences Research Council have awarded £2.5 million of funding to seven major projects intended to spur new thinking to safeguard our future water supplies. Taking private-sector funding into account, they will cost a projected £5.6 million. Each participating company has been challenged to create a new technology or process that saves or recycles a billion litres of water a day. The projects’ goals include developing unmanned aerial vehicles that can use sophisticated imaging sensors to find hidden water supplies, and treating wastewater with microwaves.
Watson joins UKERC Professor Jim Watson has been appointed research director of the UK Energy Research Centre. Currently director of the Sussex Energy Group at the University of Sussex, Watson has a long record of research and policy advice in energy systems. He’ll now take responsibility for leading UKERC’s research programme, working with scientists, users of research and other stakeholders, as well as playing an important role in defining its mission after its current funding period ends in 2014.
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News
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emperatures around the tip of the Antarctic Peninsula started rising some 600 years ago, long before humans could have begun to influence the region, scientists have discovered. But they say the rate at which it’s warmed over the last century is unusual and out of line with natural variation, though not necessarily unprecedented. Centuries of warming meant that, by the time the trend started accelerating, the peninsula’s ice shelves were already poised for the dramatic break-ups seen
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since the 1990s. The Wilkins and Larsen A and B ice shelves are notable examples. The region is now warming faster than almost anywhere else in the world. Average temperatures in James Ross Island have risen by nearly 2°C in the past 50 years. ‘Continued warming to temperatures that now exceed the stable conditions of most of the Holocene is likely to cause ice-shelf instability to encroach farther southward along the Antarctic Peninsula,’ write the authors in their report, published in Nature.
Cutting an ice core.
Researchers from Britain, Australia and France collected a 364-metre-long ice core from the peninsula’s north-eastern tip. They wanted to find out how much of the recently observed warming around the Earth is down to natural variations in the climate, and how much can be blamed on human activity since the Industrial Revolution. Their findings suggest the human influence is layered on top of the natural trend.
Jack Triest
Antarctic Peninsula primed for melt after centuries of warming
Daily updated news @ www.planetearth.nerc.ac.uk
Nutrient pollution linked to coral bleaching
Sticklebacks show initiative and leadership
Pesticide cocktails harm bumblebees
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oo many nutrients put corals at risk, a new study shows. Excessive nitrogen in the water affects their ability to cope with rising water temperatures and other environmental pressures, making them vulnerable to bleaching. That is, excessive nutrients can paradoxically cause starvation, by overfertilizing the cooperative algae on which corals depend, making them grow more quickly than the supply of phosphorus can support. This unbalanced growth makes the coral more susceptible to stress. Bleaching is when corals lose their populations of algae and fade to white. One of the greatest threats to reefs worldwide, it’s caused primarily by higher seawater temperatures. In mild cases the corals can recover; in severe ones, whole reefs can bleach and die. Scientists already knew that nutrient pollution could make the situation worse. Some of the worst bleaching around Australia’s Great Barrier Reef happens in nitrogen-rich areas, often caused by fertilizers running off farmland. But this is the first time anyone’s identified a mechanism by which the nutrients contribute to bleaching. ‘More nitrogen in the water can lead to a lower thermal threshold for bleaching – it means the corals can bleach at a lower temperature,’ says Dr Jörg Wiedenmann, a senior lecturer in biological oceanography at the University of Southampton and lead author of the Nature Climate Change paper.
tickleback fish turn out to have more complex individual personalities than you might think, showing qualities like leadership, initiative and the tendency to follow others. Fish group together to cut the risk of predation, but forming a cohesive group is hard, as individuals often want different things. The emergence of leaders and followers settles these conflicts. ‘It is a puzzling process as it means that some individuals win, while others lose out,’ says Dr Shin Nakayama of the University of Cambridge, first author of the research in PLoS ONE. Earlier research showed clear differences in appetite for risk of different fish; some are ‘shy’ and some are ‘bold’. These differences influence an individual’s desire to take the lead in a group. The new study looked at how the desire to lead depended on the results of earlier actions. If a fish tried to initiate a foraging trip but its partner didn’t follow, did it try again or give up? If it was followed, did it become more likely to try to lead in future? The researchers found that fish often switched between leading and following, and that their preference for leading depended on how successfully they’d recruited followers. Yet personality did play a part; shy individuals, less prone to lead, became discouraged if they were not followed, whereas bold ones kept trying.
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xposure to combinations of common pesticides can severely affect individual bees and whole nests, say researchers. Scientists already knew pesticides can kill bees, affecting their ability to find their way home and reducing the number of queens produced by colonies. But bees are typically exposed to many different pesticides when collecting nectar and pollen from crops, not just one. Scientists from Royal Holloway, University of London investigated the specific and combined effects of two pesticides on individual bumblebees’ foraging and on overall colony growth. Published in Nature, this is the first study of the effects of a combination of pesticides in realistic conditions. The researchers built an experimental set-up which exposed bumblebees from 40 colonies to either a neonicotinoid or a pyrethroid, or both, or neither – the bees could bypass the chemicals if they chose. It turned out that nests exposed to the neonicotinoid produced fewer adult workers. The chemical also damaged the foraging ability of worker bees, and killed many before they made it back to the hive. The pyrethroid also killed workers. But contact with both pesticides had the severest effect, increasing the risk of whole colonies perishing. Worryingly, the findings suggest the bees either don’t detect the pesticides or choose not to avoid them.
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LAKE BAIKAL
A GLIMPSE of Greenland’s future Greenland is a savagely beautiful place – a land of snow and mountains, home to the largest body of ice in the northern hemisphere. This wild and remote island is going through rapid changes that could affect millions of people across the world. Laurence Dyke explains how he and his colleagues are busy trying to predict the future of the Greenland Ice Sheet.
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4:30
am – the alarm goes off, followed by the unforgettable sound of the marine diesel engine coughing into life; sleeping bags rustle as the first heads poke out. Soon everyone is on deck, steaming coffees in hand, watching the sun rise through the coastal mountains as our little boat navigates through the shifting maze of ice. Lifting clouds reveal an overnight dusting of snow on the highest peaks and large plates of fresh ice yield with a crunch under the steel bow. Another busy day of fieldwork is underway. The GLIMPSE project (Greenland Ice Margin Prediction, Stability and Evolution), led by Professor Tavi Murray, looks at changes in the ice sheet over different timescales to help us understand how it might change in the future. My own work examines how the ice has behaved over thousands of years in response to changes in the climate. Other members of the group are interested in what is currently happening – they monitor the
ice sheet and the surrounding oceans using information from satellites, aircraft and field measurements. Back in Swansea, our colleagues combine all our results in computer models which will help predict the ice sheet’s future. Fieldwork is integral to GLIMPSE, and over the last few years we have focused on south-east Greenland, a spectacular region that has lost significant amounts of ice over the last decade. We spend most of our time working from a small (45-foot) fishing boat skippered by Siggi Petturson, an Icelander with a lifetime’s experience sailing these icy waters. Siggi is something of a legend in the local community; he is said to have once killed a large Greenland shark that threatened his crew by jumping in the frigid waters armed only with a knife. Siggi is also the perfect captain and guide, navigating his tough little boat through mazes of ever-changing ice. From the boat we take detailed oceanographic measurements within the
Far left: Sidegletscher, south-east Greenland. Icebergs are born at the large ice cliff where the glacier meets the sea. Left: Filming above the evocatively-named Vikingevig (Viking Cove), south-east Greenland.
THERE ARE FEW FEELINGS BETTER THAN KNOWING YOU ARE CAPTURING SOMETHING TRULY BEAUTIFUL.
Laurence Dyke
Tavi Murray
huge iceberg-filled fjords, as well as further out at sea. Southe-ast Greenland is affected by several different ocean currents. At the surface the very cold and fresh East Greenland Current and East Greenland Coastal Current flow southwards, sourced from melting Arctic pack ice and glacier runoff. Below is the much warmer, saltier water of the Irminger Current, an offshoot of the Gulf Stream that comes from the subtropics. Irminger water snakes its way deep along the edge of the continental shelf far offshore. In places it finds its way across the shelf through deep glacial troughs. The warm, salty water flows into the many fjords where it meets with enormous glaciers, melting and undercutting the ice and making the glaciers flow faster. We are really interested in how changes in these ocean currents can affect the glaciers. During our field campaigns we travelled along 750km of Greenland’s coast, through narrow fjords and between small islands. I was effectively ‘piggybacking’ on the boat, getting dropped ashore for a day or two at a time to collect rock samples and make land-based observations. I am trying to reconstruct how the ice sheet has changed over thousands of years using clues from the landscape and a technique called cosmogenic isotope exposure dating. The Earth is constantly bombarded by high-energy ‘cosmogenic’ particles from deep space; these collide with
rocks on the Earth’s surface to form ‘exotic’ isotopes such as Beryllium-10 (10Be). An isotope is an atom with an irregular number of neutrons; 10Be has one more neutron than the more common Beryllium-9. Over time, these rare isotopes build up in exposed rocks, and by measuring their concentration we can work out how long the landscape has been exposed to the atmosphere since the ice sheet retreated. We took the samples from Greenland to the NERC Cosmogenic Isotope Analysis Facility in Scotland, where they were analysed in a highly sensitive accelerator mass spectrometer which counts individual atoms of cosmogenic isotopes to give an exposure age. By looking at the exposure history of a large area we can find out, not just when the region was last covered by ice, but also how quickly the ice retreated. This is vital information to understand how ice sheets respond to climate changes. Earlier results from south-east Greenland, published by Durham University researchers, showed that the land started to become ice-free around 11,000 years ago. Recent work from GLIMPSE shows these changes were dramatic and rapid, with glaciers retreating from the 80km-long Sermilik Fjord in as little as a few hundred years. This fast retreat suggests strong sensitivity to climate warming at the end of the last Ice Age. Results from my samples will build on this work, showing whether glaciers across the region behaved in a similar way; I will also try to identify the different factors that caused deglaciation. Sharing science with the world The scientific part of my project takes priority in the field, but I am also involved with communicating our findings more widely. As a NERC CASE student I work with an industrial sponsor, in my case a TV production company: 196 Productions, based in Cardiff. Together, we have produced a 50-minute documentary to tell people about the project and the Glaciology Group’s wider work. Before travelling to Greenland I learned how to use a professional video camera, how to interview and how to film for
documentaries. We want to document our research, but also to show what it’s like to work in this magnificent landscape. It took a lot of time behind the camera before I shot anything good, but I was lucky enough to go back to Greenland several times, with continual critique and encouragement from 196 Productions. Filming can be exasperating and timeconsuming, but also extremely rewarding – there are few feelings better than knowing you are capturing something truly beautiful. In Greenland I was privileged to witness some wonderful moments; in retrospect we were incredibly lucky. As a result our film includes spectacular sunrises, a storm amongst the icebergs, a close encounter with a polar bear and, courtesy of GLIMPSE postdoctoral fellow Dr Tim James, time-lapse footage of a huge mass of ice calving off the Helheim Glacier. On returning to the UK, we worked through nearly 24 hours of video, logging it all and developing rough script ideas. We interviewed members of the Glaciology Group and finished the script before editing the film, fitting the footage to the script. We were also awarded some funding from the Engineering and Physical Sciences Research Council to produce animations to explain some of the more complex scientific concepts. The editing process was tough but really interesting and I learnt a lot more about the shots needed to create a successful film, mostly from my own frustrations at missed opportunities. The film A GLIMPSE of Greenland: The disappearing ice is now complete and a tenminute trailer is available at the Swansea Glaciology YouTube channel. Over the next few months we hope to find a sponsor to produce DVDs and accompanying educational materials and, if possible, get the documentary aired on television. MORE INFORMATION Laurence Dyke is a doctoral student in Swansea University’s Glaciology Group. Email: L.DYKE.330856@swansea.ac.uk GLIMPSE film trailer: www.youtu.be/opid81mxkkI
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No stone unturned Local geology gives historic towns and buildings their unique character, but just as buildings fall into disrepair many local quarries have been lost too. English Heritage and the British Geological Survey teamed up to help protect this overlooked resource.
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lison Henry is an architectural conservator for English Heritage (EH). Her job is to make sure our historic buildings, grand and humble, survive the test of time. But finding the right stone to patch them up can be a challenge. It’s not just about matching the colour and texture. Stone ages and weathers depending on its mineral make-up and porosity; repair a building with something that’s too hard and you’ll hasten the decay of the surrounding structure. But even when you can identify the original building stone, there’s no guarantee the quarry it came from hasn’t been filled in or built over.
‘The sources of many of our common building stones are well known,’ explains Henry. ‘But no one had systematically identified local building stones, so sometimes there was no way of knowing if a local source was still available.’ ‘Some of the information we had to work with was even misleading; the early listed building descriptions for south Somerset record almost all orangey-brown-coloured buildings as being made of Ham Hill stone, but many of them were built of less well-known stones that were only used in a limited area.’ And while a historic building is hard to miss, many small quarries have simply been lost in the mists of time. Local authorities
are charged with protecting mineral resources, including building stones, and have to flag potentially important sites when considering development applications, but they can’t protect resources they don’t know about. So EH commissioned the British Geological Survey (BGS) to help identify and record, county by county, the sources of all the building stones used in England. The Strategic Stone Survey (SSS) would provide planning authorities with the information they need to find and protect important quarries – thereby ensuring historic buildings could be looked after too. BGS was the obvious partner. The organisation already had a database of
active mines and quarries plus an archive of building stones and their sources going back to 1835. It turns out that Henry De la Beche, the first director of what was then the Ordnance Geological Survey, had a particular interest in building stones and always included them in his observations – laying the foundations for future recording practice as well as the 3500-sample collection of stones that BGS now looks after. It was a huge task which demanded a thorough and systematic approach and the help of many local experts. BGS first trawled its own records and maps to produce a list of building stones for each
county, used in everything from cathedrals to cottages, industrial buildings and even kerbs and paving. Local geologists and building historians then set to work to identify a range of villages and structures that represented standing examples of all the stones used. BGS then mapped and recorded the sources of every stone, using historic Ordnance Survey maps and other archives. The information is all available on BGS’s English Building Stone Pits (EBSPits) website, together with details of the scarcity of each stone, the extent of unworked sources and information about potential substitutes. Graham Lott is the latest in a long line
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MORE INFORMATION Atlases describing the building stones of the counties covered are available as PDF downloads from www.bgs.ac.uk/ mineralsuk/mines/stones/EH_atlases.html www.english-heritage.org.uk Strategic Stone Study: www.bgs.ac.uk/ mineralsuk/mines/stones/EH_project.html
of BGS building-stone enthusiasts. He welcomed the project as an opportunity for BGS to make the most of its existing records and knew that the final product would be crucial for meeting the growing demand for help with historic building repairs. In fact it turned out to be an even richer resource than he had expected. ‘So many more stone types had been used than people realised,’ says Lott. ‘Shropshire in particular was a real eye-
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opener; the project turned up loads of small quarries that had served really small areas – some were used for just one or two farms. The geology there is very complicated and lots of stone types outcrop at or near the surface.’ There is still work to do, but for the 34 counties covered so far Lott and Henry are confident they have identified most sites that operated as a building-stone quarry. Hits on EBSPits are increasing, as are
requests for help identifying stones for historic building repair, on every scale from the redevelopment of St Pancras to renovating local churches. Local authorities have the evidence they need to protect historic quarry sites, and architects and conservators can identify likely sources of the stone they need – and not just for repairs. ‘This work is really important for new build too,’ explains Henry. ‘Finding the right match is crucial for the extension of historic buildings and for new buildings in architecturally sensitive areas.’ So far the survey won’t tell home-owners what their house is made of, but the painstaking work means England’s historic towns and landscapes have a much better chance of being sensitively developed and enjoyed without losing their local colour.
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he long polar winters can pass slowly on an isolated research outpost. Dr Cas Findlater of the British Antarctic Survey decided a photo competition for the intrepid staff wintering at the Halley research base would help pass the time. Word soon spread, and staff at the other BAS research stations proved keen to get involved too. The images were recently judged, with winners chosen from each station in both ‘light’ and ‘dark’ categories, as well as an overall winner. As you can see, some of the entries were truly spectacular. The top image is the overall winner, taken by Alistair Wilson at the King Edward Point base on South Georgia. Middle is the winner of the dark category for the Rothera base, taken by Tim Jackson, and the bottom image, from Cas Findlater, is the ‘dark’ winner for the Halley base.
Pictures from the polar winter
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With the long, dark nights of winter well upon us, it’s hard to imagine how we’d get around easily without street lights. But how do these bright lights affect nocturnal creatures, like bats, that are comfortable in the dark? Richard Hollingham and bat ecologist Emma Stone from the University of Bristol met up in the city centre at dusk, in the hope of finding out. But the evening didn’t quite go as planned.
Blinded by the light
Kim Taylor/Nature Picture Library
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Emma:
Richard:
We’re stood on the Feeder Road behind Bristol Temple Meads railway station, beside one of the main rivers that runs through the centre of the city – it’s used for fishing and boating. And there are lots of pipistrelle and Daubenton’s bats here in the summer; they roost in the old warehouses along the river.
Well, it’s been getting darker and darker. I see you’ve got a bat detector.
Richard: It’s a fairly grim location: we’re stood underneath a willow tree in the pouring rain, the river is a murky brown, the road’s behind us and we’re both shivering. And you say there are bats in the warehouses on either side of the river?
Emma: Yes. The species that roost in the city centre always pick out the greenest areas to roost in, because these nice overhanging willow trees provide shelter for insects, which the bats feed on. Pipistrelles roost in pretty much anything, so they’re quite happy in a building, or a crack or crevice the size of your thumb.
Emma: Each bat species echolocates at a different frequency. So if you tune the detector to the right frequency, you can tell what bat you’re listening to. We’ll see if we can pick up any pipistrelles, because they’re the most common species around here. They echolocate at 45 kilohertz, whereas soprano pipistrelles echolocate at 55 kilohertz, hence their name.
Richard: We’ve been here for about half an hour now and so far we’ve seen several seagulls, a boat and many cars behind us, but still no bats.
Emma:
So what’s the fascination with bats?
I think in the next 20 minutes or so you’ll start to get a few bats coming out. The bats have been doing strange things this season. They’ve delayed giving birth, basically because we had such bad weather in April, which meant they couldn’t go out and forage.
Emma:
Richard:
They’re very interesting animals. They use echolocation – which is fascinating – and they also use vision. They’re much more efficient at flying than birds are: they’re highly manoeuvrable. There are so many things to like about bats.
It’s like a grim episode of Springwatch isn’t it?
Richard:
Richard: And you’re interested in how street lights affect them?
Emma: Yes, we’re trying to find out how having more street lights, and different types of street lights, affect bats. All UK bats are protected, so we need to know how best to mitigate any negative effects of these lights.
Richard: What have you found so far?
Emma: Well, we took standard sodium street lights out into the field, and put them along lesser horseshoe bat and pipistrelle flight routes, to see how the bats responded. We found that they actively avoided the lights – they didn’t fly along their normal routes.
Emma: There aren’t any bats, but I think if I was a bat, I would be staying in bed too. It’s a bit chilly.
Richard: Well at least this is realistic. This is what wildlife watching, wildlife listening, is all about. You actually spend a lot of time standing around with nothing happening.
Emma: Yes, you spend a lot of time not seeing much, and then you get those lovely genius moments and those little glimpses – that is what you wait for, but you can’t guarantee them. Animals don’t read the textbooks, they do what they want and you can never predict it. But that’s the beauty of it, because you never know what you’re going to get from one day to the next. We’ve just been unlucky tonight.
Richard: As well as these sodium lamps, you also looked at LED lights didn’t you? They’re promoted as environmentally friendly, because they use less energy.
Emma: We wanted to look at lights that are being promoted as green technology and find out if they really are green for biodiversity. So we did the same experiment: we took the LED lights out into the environment to see if they affect the bats’ commuting routes. And unfortunately we found that they had the same effect as the sodium lights. So these bats don’t like LED lights either.
MORE INFORMATION This Q&A is adapted from the Planet Earth Podcast, 17 July 2012. The full podcast and transcript are on Planet Earth Online http://planetearth.nerc.ac.uk/ multimedia/story.aspx?id=1256 For more information about the bats and lighting research project visit www.batsandlighting.co.uk/
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Squat lobsters exploring a black coral on the Logachev Mounds.
Cold corals in hot water? Cold-water corals face an uncertain future as increasing CO2 in the atmosphere changes the chemistry of our oceans. Laura Wicks set sail on the Changing Oceans Expedition to find out how these amazing animals are likely to fare.
H
idden deep in all the world’s oceans are the vast mounds and reefs of cold-water corals. They grow much more slowly than their tropical counterparts but can still extend over huge areas: reefs of Lophelia pertusa off Norway cover around 2000km2 – more than tropical reefs in the Seychelles, Belize or Mozambique. The corals build their skeletons from calcium carbonate dissolved in the seawater, creating complex 3D structures that persist even after the animal itself has died. These skeletons support thousands of species, including many that we eat. But the life of these hidden corals is under threat. The amount of CO2 in the atmosphere has increased exponentially since the Industrial Revolution and much of it is dissolving into the oceans, slowly increasing the acidity of seawater. The pH of the sea is currently about 8.1, but this is predicted to drop by about 0.3 pH units by 2100. It doesn’t sound like much, but this small change can have huge implications for marine organisms that rely on calcium carbonate, like corals, shell-producing animals and calcareous algae. This is because the increasing concentration of dissolved CO2 in the oceans decreases the carbonate saturation of the water, so there is less carbonate available for coral skeletons and shells. This acidification of the oceans, often referred to as ‘the other CO2 problem’, may be the biggest threat facing marine calcifying organisms today. In May 2012, I set sail for the North Atlantic on the RRS James Cook, part of an international team of scientists on the Changing Oceans Expedition. Our mission was to examine the potential impact of ocean acidification and warming on cold-water coral reefs and the creatures they support. In our four weeks at sea we visited a range of cold-water coral
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sites, from the ‘shallow’ reefs of Mingulay in the Outer Hebrides (around 130m deep), dominated by Lophelia pertusa, to the Logachev Mounds, west of Ireland; nearly 1000m deep and spectacular with both Lophelia pertusa and Madrepora oculata. We don’t know a great deal about either species of coral, or the ecosystems they form, because they are so inaccessible – you can’t just dive in and explore them like you can in the tropics. Before we could even think about collecting samples we had to find the reefs. To do this we used advanced acoustic techniques, such as multibeam and sidescan sonar, that use sound waves to create an image of the seabed from which we could pick out possible mounds of coral. The next step was to send down our robot, the Remotely Operated Vehicle (ROV) Holland I, to take a closer look. During each ROV dive the excitement in the lab was palpable. The ROV’s high-definition cameras beamed up spectacular images of the reefs beneath us. Fish darted across the screen and unusual sponges and crabs came into view, causing a buzz as we tried to work out exactly what they were. But we weren’t just there to watch. As part of ‘Team Coral’, I carried out short-term experiments to see what effect ocean warming and acidification have on the growth and overall health of the corals. Using samples carefully collected by the ROV’s robotic arms, we kept Lophelia pertusa and Madrepora oculata in specially designed tanks for the duration of the cruise. We manipulated the temperature and CO2 levels in these ‘minioceans’ to mimic one possible set of future conditions, in this case a 3°C increase in temperature and a near-doubling of atmospheric CO2. We then measured the respiration and growth rates of the corals over three weeks. My team-mates looked at how other aspects of the corals’ biology responded to their changing
Coral images: Changing Oceans Expedition
Above: A black coral amongst dead Lophelia rubble. Below: Laura and James Burris setting up a stand-alone pumping system (SAPS) to measure the amount of carbon around the coral reefs.
Laura Wicks
environment, including microbial communities and protein expression. All of an animal’s biological processes, such as growth and respiration, are controlled by proteins, so changes in the concentration of various proteins give us a clue as to how processes like calcification may respond to increased temperature and ocean acidification in the future. Along with longer-term experiments under way at Heriot-Watt University, these will help us to work out how the corals will respond to global climate change – whether they can adapt, or whether ultimately it will be impossible for them to survive. Alongside the ROV campaign, a host of other activities took place out at sea. One was the deployment of the CTD and SAPS. CTD stands for conductivity, temperature and depth, which this particular instrument measures at the bottom of the ocean. Attached to the CTD frame we had a SAPS – Stand Alone Pumping System – which is a big pump with a filter and timer. We use the SAPS to look at the amount of particulate organic carbon (coral food) that is reaching the reefs. When it reaches the seabed the pump switches on and records how much water flows through its filters, which capture the organic carbon. Back in the lab, we analyse the amount of carbon on the filters and the water flow, to calculate how much food the corals have access to. Combined with surveys of the reef and CTD data, this information can help us understand why the corals live where they do, and how any future changes in climate and currents may affect these ecosystems. Four weeks at sea passed by in a flash, and everyone on board collected a wealth of information. Now we’re all back on dry land, it’s time to process samples, extract data and try to understand what the future holds for these cold-water creatures as our oceans change.
MORE INFORMATION Dr Laura Wicks is a postdoctoral researcher at the Centre for Marine Biodiversity and Biotechnology, Heriot-Watt University. Email: L.Wicks@hw.ac.uk. The Changing Oceans Expedition is part of the UK Ocean Acidification Research programme. www.changingoceans2012.blogspot.com
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You heard it here first Halley team, 1971.
An unofficial history of Britain in Antarctica Formal records are generally silent about the human details of events, the things that really bring the past to life. The British Antarctic Survey’s (BAS) oral history archive gives a new view of the British endeavour in Antarctica, focusing on the period from the first continuous British presence there, during Operation Tabarin in 1943-45, to the present day. It includes testimony from a wide variety of people, including those who served the Falkland Islands Dependencies Survey (FIDS) and BAS. The bulk of this collection is the work of the ongoing British Antarctic Oral History Project (BAOHP), which so far has 200-plus audio and video recordings. The recollections of men and women who worked in Antarctica give a unique perspective on the social, scientific and political interactions of their times, the development of polar science and technology, and the hardships, triumphs and eccentricities of everyday life in one of the world’s most hostile environments. The audio recordings from which the following extracts are taken – plus many more – are available on the British Antarctic Oral History Project webpages.
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An unofficial history of Britain in Antarctica
Petra Searle Directorate of Overseas Surveys map officer 1953-60, BAS 1984-88
Women didn’t go further south then, it just was not done. Sir Raymond1 was from the heroic age, women stayed at home and waited for their men to come back again. Women didn’t start going south certainly until Bunny2 had retired. I think probably Dick Laws3 was against it as well. For one thing the accommodation on the ships was much more suitable. I think the ones that did go journeyed round on the ship, saw the bases then came home. I saw a lot of life in the Falkland Islands. I kept a diary of that time and it was a really exciting, different thing for me. 1 Sir Raymond Priestley became director of FIDS in 1955. He had been a geologist with Shackleton in 1907-09 and with Scott in 1910-12. Vivian Fuchs, first director of FIDS. Laws, director of BAS 1973–1987.
2 Sir
3 Richard
Stuart Lawrence Ship’s master 1970–2003
RRS Bransfield was BAS’s main supply vessel from 1970 to 1999 and was in the Southern Ocean during the Falklands conflict. Everybody was wound up, it’s not surprising that they were. I was woken at about midnight to be told the whole ship was being taken over and they were going to sink her in the narrows in the entrance to Stanley Harbour. They’d got somebody in the engine room who was on their side, and it was all definitely going to happen. So I sat them all down and said, ‘OK, let’s talk this through. But before we do that, anybody want a drink?’ So I got a case of beer out and everybody had a beer, then another case of beer and everybody had a beer…. By the time six o’clock rolled round I’d sat there for about six hours, with my brandy and my cigars, letting them have their say, and we continued on our way rejoicing.
Peter Robert ‘Bob’ Bond RAF pilot seconded to BAS 1960-63
There was quite a sizeable cargo area [in the Single Otter aircraft] and you could get a dog sledge in there with dogs either side quite happily. If you needed to transport a dog team we put the sledge in first then tied the dogs down either side of the fuselage so they couldn’t get at each other – huskies love to get at each other. We would have the lead dog up front with us. He’d sit between the pilot and whoever else was up front, tied to one of our seats, so he could sit up there and keep an eye on them. And that suited his status, he was something special. We turned the heat up full and generally speaking they went to sleep, which was nice.
Julian Taylor and Alan Precious 1954-55
Julian and Alan were charged with monitoring the dogs’ health. Ron Mottershead and I built – I don’t know what you would call it – a dog’s urinal. We did it with sheet metal, a sort of big square funnel with a grid on top and the dogs were supposed to stand on the grid and do a wee wee, which would be collected underneath in a suitable vessel. Only the dogs wouldn’t cooperate… …No and you complained bitterly when I boiled the faeces … … So the next thing was to hang around with a bucket of some kind and when they cocked their leg up at the base of the hut you collected it as it came out, and gave it to Julian.
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Alan Wright Surveyor 1961-62
Vicky Auld Physicist and base commander 1997-2008
[At Birmingham University] A BAS man came and gave a lecture – I’d just seen a poster and thought that looks pretty exciting. I had a word with him after that talk and he said, they’re not actually taking women down there for any physics-based work, so come back in a couple of years and see what we’re doing. That was 1994. So I went and did a Masters in atmospheric science. I was brought up to think I could do anything I wanted; to suddenly find out there were still careers that were closed off to women quite surprised me. There were women doing summers, but it was the wintering positions I was interested in.
I had one experience on Bransfield – I lost the tent. It is bad weather up there – you’re in the cloud very often and you can’t see any detail. I went out to feed the dogs and then went to the toilet, and I lost the tent – completely! Luckily by then I knew how you could make the dogs howl. So I worked my way upwind and howled, which I hoped would set the dogs off. Then I went downwind and I picked up the sound of the dogs, so I could go back upwind to the dogs, and then I found the tent.
John Croxall Bird biologist 1976-2006
We got a bit of an alarm call – the albatrosses aren’t doing too well. Our first thought was: is this something to do with us? We were studying them fairly intensively, disturbing some colonies on a daily basis. We quickly set up controls – areas where we didn’t go – and found, actually no, it didn’t seem to be us. We then started to look at the ringing recoveries. We knew these species migrated to Australia and New Zealand as we had ringing recoveries from there since the 1960s in the BAS archive; now we were getting a completely different pattern – all these birds reported from fishing vessels, many in the Atlantic or the Indian Ocean. So something completely strange was happening. That led to the recognition that it was a problem to do with fisheries. And we started to team up with other people, who had been on fishing boats and seen albatrosses being killed. We had data on population-scale impacts and enough data on marine recoveries to make at least a plausible case. From that we felt, not only did we have a huge responsibility to document this, we actually had some responsibility to fix the problem.
John Huckle Helicopter pilot 1956-62 We were sending a surveyor to the top of Tower Island by helicopter, and the helicopter as it came in to land stirred up a great deal of loose powder snow which gave the pilot a white out and he unfortunately missed his landing. And the helicopter overturned and of course was smashed up. Later on there was an inquiry into what had caused the crash. The colonial secretary asked the surveyor, ‘What did you think when the helicopter overturned as you landed?’ And the surveyor said, ‘Well, it was the first time I’d ever flown in a helicopter and I didn’t know quite what to expect, but it did seem a bit peculiar when I found myself hanging upside down.’
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An unofficial history of Britain in Antarctica
Derek Clarke fids Diesel mechanic 1953-61 Remembering close encounters with whales The first thing is you hear the noise – the whales blowing up. Then after a while you can see the open water in the distance. But the main thing is the dogs tend to make for that sort of thing, they might think it’s a penguin, a seal – something to eat, you know. They tended to draw you towards it. On the main route there were quite a few small holes; there was a bottlenose whale and a couple of grey whales, and the bigger pool was the killer whales’, they were looking round at the top. But the others would come up on the edge of the ice and just rest there, and you could just go over and give them a little tap. ‘So you were patting killer whales..?’ Not the killer whales, no! We’d draw the line at killer whales.
John Croxall Bird biologist 1976-2006 That was the walk I never tired of doing, even on a Sunday when you had the hangover from hell. You had to go up 250m of pretty steep climb to get off the base, but then this panorama opens up and you’ve got this wonderful short-sward grassland flanked by tussock, with screes to the left and this wonderful view out to the Willis Islands and the ocean on your right. The whole of the meadow is just full of wandering albatross. There’s this huge macaroni penguin colony, you can hear it – it’s like a football crowd, as you came over that ridge the crowd applauded! If it was a blue day with icebergs in the background you’d sit down, you couldn’t keep walking, you just had to stop and take it all in. It was just such a magnificent spectacle, still a view to conjure with.
Richard Taylor Meteorologist 1954-56
The most wonderful thing – the most joyous thing – was the actual beauty of the place, and the physicality of it. I can still remember now those times when you had really marvellous, perfect sledging weather. You had this deep blue sky, this whiteness everywhere; you’re on the sea ice, the surface is just beautiful, it’s crisp and you can just skim over it. And around you this wonderful fjorded coast and these magnificent 6000ft peaks. And you had the dogs, so excited too. The exhilaration and the purity of it was just magnificent. And all the petty little squabbles were totally forgotten – this made it all absolutely worthwhile.
MORE INFORMATION The BAOHP is a collaboration coordinated by the UK Antarctic Heritage Trust (UKAHT) and involving BAS, BAS Club and the Scott Polar Research Institute (SPRI), and additional funding partners: www.ukaht.org/outreach/oral-history A detailed database and access to all archived items is available through the BAS Archives Service. The service holds a unique resource of physical and digital collections, including scientific data, maps, administrative records, publications and artwork. A list of interviews and audio clips held by the archive is available online: www.antarctica.ac.uk/oralhistory Email: Ellen Bazeley-White or Joanna Rae basarchives@bas.ac.uk
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Can butterflies keep cool in a warming world? Moving to new habitat could allow animals to cope as climate change makes their old haunts less suitable. But will this work in practice? Andrew Suggitt’s work suggests there’s no simple answer.
T
he difficulties that climate change can create for wildlife are well known. Many species will need to migrate substantial distances to higher ground or towards the poles in order to stay within their preferred temperature range. Microclimates, or local variations in environmental conditions, present an intriguing idea: what if species could use this variation to find their required temperature niche in a warmer world? Such behaviour might allow species to adapt to climate change while remaining where they are, similar to the use of ‘microrefugia’ – small climatic refuges – when glaciers last covered much of the landscape. This could render migrations across hostile, humanmodified landscapes unnecessary. To test the idea, we used data from the wonderfully rigorous British and Catalan Butterfly Monitoring Schemes. In Britain and Catalonia, we had two study regions that were far enough apart to be independent tests of our hypothesis, but also close enough to share common species and habitat. The schemes involve dedicated volunteers walking transects of a few kilometres through butterflyrich habitats every week, recording what they see. This gave us detailed information on which butterflies were in which habitats, and when. Combined with yearly climate information, this let us measure how the butterflies respond to changes in the climate. So what did this hard work reveal? What came out was a mixed bag. Most species we tested responded as expected – that is, they used cooler habitats in warmer years, and vice versa. Three
quarters of the species used cooler habitats in Catalonia than in Britain, confirming our hypothesis that the hotter the climate, the more likely species are to seek refuge in cool habitats like shady woodland. When comparing the annual differences to the regional ones, a similar proportion of the butterfly populations shifted habitat per unit of temperature change; another encouraging sign. So far, so good. But – and there nearly always is a ‘but’ – these effects were small, in terms of the proportion of each population that was undertaking the shift. On average, only around 6-7 per cent of individuals were found in different habitats in response to the temperature difference between Britain and Catalonia. Like most ecological analyses, a clear and precise prescription for conservation was elusive. The effect seemed to be widespread, but the butterflies’ response wasn’t enough to merit actions based solely upon it. We also couldn’t tell what mechanism was responsible for the habitat shifting. Was it simply different rates of survival between the habitats? Was it genuine movement of individuals to preferred habitats? Or was it just a difference in the amount of time spent in each habitat? These questions will likely be the subject of further work as we try to unpick how individuals use habitat at the local level. But thanks to the true commitment of hundreds of volunteers, we are at last beginning to understand how species’ habitat associations might alter with climate change.
MORE INFORMATION Dr Andrew Suggitt is a biologist at the University of York. Email: andrew.suggitt@york.ac.uk
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Jordi Jubany
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This work formed part of a NERC Ecology & Hydrology Funding Initiative project, ‘The impact of climate change on habitat use: implications for predicting species’ range changes.’
Ocean acidification – no enemy to anemones Many are deeply concerned about how ocean acidification will affect marine life. But if some organisms will be badly hit, the work of David Suggett and Jason Hall-Spencer suggests others will flourish.
O
cean acidification (OA) is the process by which the pH of the oceans falls as they absorb more carbon dioxide (CO2) from the atmosphere – the lower a solution’s pH, the more acidic it is. Substantial declines in ocean pH are predicted for this century as anthropogenic emissions continue to raise atmospheric CO2 levels; therefore, intensive international efforts, including the NERC-funded OA programme, are trying to unravel how OA will affect marine ecosystems. Unsurprisingly, calcifying corals have been a major focus of these endeavours. Corals are the foundation for the high productivity and biodiversity associated with reef ecosystems, which in turn support the livelihood of millions of people worldwide. Research has shown that corals and other calcifying organisms – ones which produce outer shells or skeletons of soluble calcium carbonate – will be corroded by ocean acidification (see p18). However, new research led by the Universities of Essex and Plymouth has shown non-calcifying
relatives of corals can thrive under ocean acidification conditions. We examined what happened to these creatures with increasing proximity to a natural CO2 vent site on the seabed near the Italian island of Vulcano, where CO2 (and pH) conditions are similar to those predicted for much of the world’s oceans in 50-100 years.
anemones with more energy to grow. Elevated CO2 is not the only factor that seems to favour the dominance of sea anemones. Localized eutrophication (addition of excess nutrients, often due to run off from farms) and blast fishing can also result in ‘blooms’ of anemones as well as soft corals. So local environmental pressures, as well as climate change, appear
ALTHOUGH CALCIFIED ORGANISMS DISSOLVE AWAY, SEA ANEMONES GROW LARGER AND MUCH MORE ABUNDANT WITH INCREASING CO2 AVAILABILITY. Our observations, recently published in Global Change Biology, reveal that while whole calcified organisms dissolve away, sea anemones grow larger and much more abundant the more CO2 there is. This is, at least in part, because CO2 appears to increase the productivity of the symbiotic algae that live in cooperation with the anemones. In effect the CO2 provides the
Demetris Kletou, University of Plymouth
to favour this group of organisms. Sea anemones perform essential and unique ecological roles in temperate and tropical ecosystems. So we need to understand just how widely our current observations of anemones under high CO2 conditions apply. Will all anemonealgal symbiont combinations respond in the same way? Will other non-calcifying relatives of corals, such as jellyfish and soft corals, also thrive in a high-CO2 world? What are the wider ecological and biogeochemical ramifications of these changes? Ultimately, calcification will inevitably be more difficult for corals – that is, more energetically costly – as ocean CO2 concentrations continue to rise. We now need to identify just how well noncalcifying corals and their close relatives can take advantage of the space left behind.
MORE INFORMATION Dr David Suggett is a senior lecturer in marine biogeochemistry at the University of Essex; Professor Jason Hall-Spencer is a marine biologist at Plymouth University. Email: dsuggett@essex.ac.uk The research described here was partly supported by NERC’s Ocean Acidification programme; for more information, see www.oceanacidification.org.uk
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Can money grow on trees? Peter Newton (below) describes his work investigating whether medicinal oil could help provide income for people living deep in the Amazon.
A
ntonio taps the bark hopefully with his machete: ‘Espero que ela vai dar muito óleo,’ he declares. I hope that she’ ll give us a lot of oil. Ten minutes later he is sweating with the effort of drilling a 15cm-deep hole into the hardwood trunk with a hand-borer, but his wish is granted and the familiar trickle of copaíba (cop-ay-ee-ba) oil begins to seep from the tree. Pensamento grabs the waiting plastic tubing and deftly fits it to the hole. Already attached at the tubing’s other end is an empty two-litre plastic drinks bottle, which now begins to steadily fill with the coppercoloured oil. The three of us are in a remote part of the Brazilian Amazon, collecting medicinal copaíba oil as part of a study of the potential for forest resources to provide an income for families living here. Antonio has been harvesting copaíba his whole life, but only occasionally and only to use at home as a medicine. Now, new opportunities are emerging, and a nongovernment organisation (NGO) working in the area has asked us to see if it’s feasible for them to train and equip local people to harvest the oil commercially. And so we have formed our team: me and my colleagues from the University of East Anglia, with an interest in the sustainable use of tropical forests, and ten local Amazonians, who are keen both to
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share their knowledge and to learn more. Copaíba harvesting has only ever been opportunistic here, not systematic, so by drilling trees throughout the study area and recording what we find, we hope to build up a more complete picture of the possibilities. Our study site is the vast (900,000ha) extent of two sustainable-use reserves: the primary forest here is interrupted only by meandering rivers. Small communities of Amazonians live by fishing, hunting, harvesting forest plants and growing crops such as manioc. People are largely self-sufficient. They have to be; there are no shops or roads here, and the reserves are a 12-hour boat ride from the nearest town, Carauari, itself a week’s river journey from the state capital, Manaus. Governments and NGOs in tropical forest countries around the world are increasingly recognising that people living in rural areas need help to find ways of earning a living that don’t damage the forest. One option is to develop local industries based on collecting and selling forest resources. There is a growing demand both in Brazil and abroad for sustainably-sourced rainforest products – health food shops in the UK regularly stock products made from Brazil nuts, açai palm fruit and – increasingly – copaíba oil. This natural oil is stored in the trunks of copaíba trees (various members of the Copaifera family). Brazilians have used it for centuries to cure colds and flu, and to help treat wounds and infections. This is no placebo; colleagues at the Federal University of Amazonas,
Brazil, have spent years documenting the biochemical compounds behind its healing properties. Harvesting from the forest – profits and perils On the face of it, copaíba is as close as you’ll find to money growing on trees – or at least, dripping out of them. In Carauari, the oil sells for $7 a litre, and we drilled trees that yielded up to four litres of oil within 24 hours. The average household income in these communities is just $275 a month, so a sale like this would be a welcome financial boost to a family. There are some catches. Nine different species of copaíba are found in the Brazilian Amazon alone, and not all are created equal – as we found when we began experimentally drilling trees of different
Left and below: Drilling for copaíba oil.
sizes and species, and in different types of forest. In fact, most trees didn’t yield any oil at all. Even those that did showed huge variation in volume – many produced less than 100 millilitres. It takes time and effort to locate and drill a tree and if it turns out to be hollow, or to contain little or no oil, that effort goes unrewarded. Collecting forest products as a moneymaking option has other downsides, too. Travel by river is costly, either in time spent paddling or in fuel. Passing through the forest on foot is hard work and dangerous. Snake bites are one of the most common
causes of injury in this region; I was lucky to escape unscathed when an unseen Bothrops – a kind of venomous pit viper – struck out at the bottom of my boot. No surprise that many Amazonians have opted to focus their efforts on agriculture. Nonetheless, experience shows that if the rewards are sufficient then people will go into the forest. A few years ago, a cooperative in a neighbouring community established a small plant to process the oil found in andiroba seeds, the product of another Amazonian tree. Now, almost every family on the river spends a couple of weeks each year collecting their quota of seeds, to sell on to the cooperative. Could a similar system be developed for copaíba oil? A key unanswered question that would determine whether harvesting copaíba trees could be truly sustainable was whether oil could be extracted from an individual tree more than once. Anecdotal evidence suggested it could, but common consensus held that it might take several years for trees to replenish their stocks. To find out, we returned to trees that had been drilled either one or three years earlier. We found that they were just as likely to produce oil as were ‘virgin’ trees. Although they only produced around half the original harvest, here was firm evidence
Above: Andiroba seeds drying.
that a profitable volume of oil could be extracted from a tree just a year after its first harvest. Having worked out the rate at which oil could be collected, our task was to compile data on oil volumes, prices, tree densities and travel costs – all the factors that together determine whether it’s worth harvesting a resource commercially. We estimated that the reserves contained more than 38,500 litres of oil, and that harvesting just two litres per family per month would generate five per cent of an average household’s income. There are still some uncertainties – such as whether oil extraction has any longterm impact on a tree’s health, and how many times a tree can be reharvested. But we concluded that, as long as a market for the oil could be secured, then copaíba harvesting could complement andiroba seeds, rubber and other forest products as a source of income for men like Antonio, who are trying to support their families and look after the forest at the same time.
MORE INFORMATION Since finishing his NERC-funded PhD in September 2011, Dr Peter Newton has been working as a postdoctoral research fellow at the University of Michigan with the International Forestry Resources and Institutions network, and the CGIAR program on Climate Change, Agriculture and Food Security. Email: newton.pete@gmail.com www.tropicalforestresearch.org/people/ pnewton.aspx.
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Adrian Glover/ Nick Higgs
Whales, worms
and the story of life What’s the point of studying dead whales and the worms that eat them? Recondite research can be more relevant than you’d think, as Nick Higgs explains.
An individual Osedax mucofloris.
‘W
hy is NERC even funding this research?’ asked a perplexed volcanology professor in my department. I had just given a nervous five-minute talk introducing my future PhD work to a bemused audience of Earth scientists. It was a question that I hadn’t given a lot of thought to, but one I have subsequently spent a lot of time considering. Since then I have been asked the dreaded question by broadcasters and teenagers alike, sometimes with a soulcrushing tone of perplexity or distain: why does your work matter? You see, I’ve spent the last three years studying whales… sort of. That’s what I say to get people interested. The truth is that I only study dead whales and, if I’m honest, I’m more interested in the worms that live on dead whales. But these aren’t just any old worms. They live only on animal skeletons at the bottom of the ocean – which they use as food. Their Latin name, Osedax, means ‘bone devourers’. Amazingly, they don’t even have a mouth or gut to digest the bones. Instead they have root-like tissues that grow into the bone and dissolve it, like fungi growing into a log. My research looks at how Osedax affect the whale’s fossilisation. Do these worms completely destroy the whale skeleton
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before it can become a fossil? What effect has this had on whale fossilisation in the past? In short, I am trying to find out how whales become fossils. Understanding how fossils form is vital to interpreting the fossil record, and that of whales is especially important. The evolution of whales is one of the best examples of macro-evolution, where one kind of animal evolves into a very different one. The fossil record provides us with an exquisite sequence of skeletons, showing how land mammals adapted to aquatic and
dinosaurs, so who knows how long Osedax has been devouring skeletons. That’s the problem; they usually destroy any evidence of their existence. The fossil record of worms is patchy, since they don’t have many hard parts, but uniquely Osedax leaves distinctive traces on bones. I’ve been using the Natural History Museum’s micro-CT scanner to study the borings of Osedax in modern whale bones. Recently, we discovered their traces in a three-million-year-old fossil whale bone from Tuscany in Italy. Palaeontological
I DO THIS RESEARCH BECAUSE I AM FILLED WITH WONDER AT THE NATURAL WORLD. then fully marine environments, becoming the ocean giants we admire today. Equally important is understanding the evolution of the worms themselves. Originally it was thought that they evolved at the same time as whales, but new findings show they can thrive on other types of bones – fish bones, for example – suggesting that they may have been able to live on the skeletons of big fish and large marine reptiles. These leviathans were around long before mammals entered the oceans and later died out with the
detective work let us show that Osedax had colonised much of the world’s oceans by this point. Another group of scientists found similar traces in a 30-million-yearold whale bone from the north-east Pacific, showing that Osedax has been around since the emergence of the whales. These two finds are just the tip of the iceberg and we need much more work to get a handle on how Osedax has affected the fossil record of whales, and other marine vertebrates for that matter. The problem is that museum collections are
Osedax worms living on a whale bone found off Japan.
inherently biased. No one wants to display a half-decayed, broken-up skeleton; they covet the most complete specimens to study anatomy. Unfortunately it is the pockridden, eroded bones that are the smoking guns of Osedax activity. For example, the fossil bone in which we discovered Osedax traces had been sitting in a dusty box for over a century and wasn’t even on the museum’s official catalogue, probably because it wasn’t much use as a whale fossil. The other problem is that small holes in bones can easily be confused with sponge borings, so palaeontologists may not even realise what they have. We need collectors and curators to keep their eyes peeled and spread the word. By piecing together the evolutionary history of Osedax, we may be able to explain some gaps in the fossil record of whales. Whether of whales or worms, the fossil record is part of the wider evolutionary story. As the naturalist John Muir wrote: ‘When we try to pick out anything by itself, we find it hitched to everything else in the Universe.’ Since evolution is what hitches us to the rest of the living world, getting it right matters. On a broad scale, research like mine helps shape how we think about ourselves and our relationship to the living world. This is not to say that there are no
immediate practical applications. History shows that fundamental research often spawns previously unimagined benefits. For instance, I am now looking at how my work on the decay of porpoise carcasses can help forensic investigators when bodies end up in the sea. Along with pioneering work by a Canadian team using pig carcasses, these studies help us understand common processes of decomposition in the sea. I have specialist knowledge of how bones decay and can identify different animal traces on them. Both give clues to how long a body has been in the water. I could never have imagined that my research would lead me down this path three years ago, but with hindsight it makes sense. I should have guessed after Osedax featured in an episode of the crime drama Bones! My research is aimed at understanding basic questions about how the natural world works, which may even have useful outcomes for modern problems. These are both great reasons why this type of science should be done. Similar arguments are routinely put forward in favour of fundamental research, but I think that these arguments lack force because they are missing a human element. I do this research because I am filled with wonder at the natural world. When I give talks on my work it is this shared
sense of wonder that connects me with my audience. It is the same awe that enthrals us with natural-history programmes on TV and enriches our lives through books and art. In the dozens of talks I have given since I first fumbled my response to the volcanology professor, the ‘why’ question has never come up first. Curiosity beats out cynicism every time. For a few moments the audience becomes part of the discoveries, they become scientists, and then they demand more information… more than I can give them. There is still a lot more to learn about the natural world and in tough economic times funding for such research is at a premium. It is therefore all the more important to acknowledge the role of curiosity-driven research in capturing our imaginations and fulfilling our primal desire to explore the limits of our knowledge.
MORE INFORMATION Nick Higgs recently finished his PhD at the University of Leeds and is now a postdoctoral research assistant at the Natural History Museum in London. Email: n.higgs@nhm.ac.uk Twitter: @BahaNick
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Slime power:
bioenergy from the sea As global oil supplies decline and greenhouse gas emissions continue to rise, the search for renewable energy sources is more urgent than ever. Joanne MacDonald and Michele Stanley explain how marine algae could be part of the answer.
Dr Michele Stanley studies which microalgae are most appropriate as a biofuel crop – here in the culture collection of algae and protozoa.
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A
ll plants turn sunlight energy and CO2 into organic molecules such as sugars and lipids (oils), which we can extract and use to produce biofuels like bioethanol, biobutanol and biodiesel. This bioenergy is likely to be a big help in reducing our dependence on fossil fuels. But the biomass – the raw materials – have to be both sustainable and economically viable, and that’s proving to be a bit of a problem. The most common biofuel – bioethanol – is made from sugar cane and maize. It currently accounts for 90 per cent of the world’s biofuel supply, with biodiesel from plant oil such as rape seed and palm accounting for the rest. But these ‘first generation’ biofuels are still far from meeting even existing demand for biobased alternatives to petroleum. And we can’t simply increase production, because these energy crops compete with food crops for land and water. So attention has turned to the other 70 per cent of the Earth’s surface – the oceans – and the potential for aquatic plants to provide a sustainable fuel source. Algae are a diverse group of photosynthetic aquatic organisms which includes seaweed (macroalgae) and microscopic floating plants such as phytoplankton (microalgae). Like other plants, algae also make sugar and oil molecules through photosynthesis. In the right conditions some species of microalgae can accumulate oil in quantities up to half their dry cell weight, and this means they have the potential to provide up to 24 times the amount of oil per acre than palm, the most productive terrestrial crop. Algae are also incredibly flexible: they can grow in a wide range of conditions including marine, brackish or nutrient-rich wastewater. All this means algae could be a highly efficient energy source. Microalgal biodiesel has other benefits over traditional land-grown biofuels. It has high levels of polyunsaturated fatty acids so it can remain fluid at low temperatures, which improves the performance of diesel engines in cold conditions. Yet despite these potential benefits to yield and performance, growing, harvesting and processing algae remains expensive. Microalgae are grown in large open ponds or in photobioreactors – artificial environments that provide light, CO2 and nutrients. But the amount of light and constant temperatures needed for optimal growth come at a price, especially in the UK where sunlight can be scarce. Using artificial light would have
Seaweed being harvested in China.
Seaweed farms could provide an answer. These are already commonplace in China where nine million tonnes of seaweed are cultivated each year. The plants are grown on long ropes held afloat by plastic buoys and harvested by hand. While most of China’s seaweed is currently used for food, textiles, cosmetics and medicines, attention is now turning to cultivating it for fuel. But Europe’s relatively high labour costs mean harvesting by hand wouldn’t be economically viable; we would need to develop a machine to harvest and process enough macroalgae for fuel MICROALGAE HAVE THE production. And crucially, we also POTENTIAL TO PROVIDE UP TO need to understand the 24 TIMES THE AMOUNT OF OIL PER potential impacts of industrial-scale seaweed ACRE THAN PALM. farms on the marine ecosystem. Macroalgae offer different opportunities. In future, micro- and macroalgae could Large brown seaweed grows very fast and is be a sustainable source of energy; there is common around the UK coast, particularly plenty of evidence to suggest that large-scale in Scotland. Because of its structure biofuels production from algae is possible. seaweed can easily be biodegraded to But there are still many unknowns. We need produce methane gas. This could provide to ensure their long-term sustainability – a local source of biogas for remote coastal economically, socially and environmentally. communities, where grid connections The next steps must include assessments are poor and gas supplies expensive. of the short- and long-term impacts of Macroalgae could also be fermented to growing algae, so we can be confident of the make ethanol. But, as with microalgae, sustainable limits of production and make using macroalgae on a commercial scale sure that marine ecosystems and biodiversity presents problems. are properly looked after. There’s an estimated ten million tonnes of seaweed around the Scottish coast, but harvesting these wild stocks could spell MORE INFORMATION disaster for the surrounding ecosystem. Dr Joanne MacDonald is NERC knowledge exchange fellow, and Dr Michele Stanley Seaweed is home to many small fish and is director of the Algal Bioenergy Special invertebrates which are an essential part Interest Group (AB SIG). of the food web for migrating seabirds. Email: joanne.macdonald@sams.ac.uk Standing stocks of seaweed also provide www.nerc.ac.uk/research/programmes/ defence against erosion and flooding, algal/ which would be lost if harvested at scale. significant economic and carbon costs at the scale required for fuel production, and even in warmer regions where light and temperature are more reliable, the costs of harvesting and processing large amounts of algae are still high. So large-scale production of algal biofuel is in its infancy, but there is considerable global investment to realise its potential. The US Navy and shipping giant Maersk have successfully tested algal biofuels in their ships and are investing in further research and development.
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