Tag Archives: Ecosystems

What happens when the world dries out

FOR IMMEDIATE RELEASE A warming world carries many threats, and now scientists have discovered that a change in atmospheric conditions could have serious consequences for soil chemistry LONDON, 1 November – A warmer, drier world will be bad news for those people who already live on the edge. Higher temperatures will do more than evaporate the soil moisture: they will alter the natural soil chemistry as well. Manuel Delgado-Baquerizo of the Universidad Pablo de Olavide, in Seville, Spain, and fellow scientists report in Nature that they looked  at soil samples from 224 dryland ecosystem plots in every continent except Antarctica. Drylands matter: they account for more than 40% of the planet’s land surface and they support more than 38% of its population. Drylands add up, in the dusty language of science, to the largest “terrestrial biome” of all. And even though on average more warmth will mean more evaporation, and therefore more water vapour in the atmosphere and more precipitation in some of those zones that already have ample rainfall, the pattern could be different in the arid lands. All the calculations so far indicate that these drylands will increase in area, and become drier with time. Already 250 million people are trying to scrape an increasingly meagre living from lands which are degrading swiftly, either because they are turning to desert, or because they are overgrazed.

Hard on microbes

But to make things worse, climate scientists predict that between 2080 and 2099, soil moisture will decrease by between 5% and 15% worldwide. And that in turn could have a profound effect on the levels of carbon and nitrogen nutrients naturally in the topsoils. What keeps soils alive, and productive, is the compost or humus of leaf litter, animal dung, withered roots and other decaying vegetation in the first metre or so of topsoil: this in turn feeds an invisible army of tiny creatures that recycle the nutrient elements for the next generation of plant life. But these microbes also need water to thrive. The consortium of researchers predicted that as the soils got drier, biological activity would decrease, but geochemical processes would accelerate. That is, nutrients that depended on little living things in the soil would drain away, but other elements – phosphorus among them – would increase, because they would be winnowed from the rock by mechanical weathering or erosion. The research team tested this argument with samples from 16 countries, including the Negev desert in Israel, the woodlands of New South Wales in Australia, the Altiplano of Peru, and the Pampas lowlands of Argentina.

Balance upset

These regions could all expect from 100mm of rainfall a year to 800 mm; all soil samples were analysed in the same laboratory in Spain. And as predicted, they revealed an increasing imbalance: more phosphorus, less carbon and nitrogen as they became drier. Such a trend would actually feed back into global warming: ideally, more vigorous plant growth would absorb more carbon dioxide. But if vegetation wilts, and soils turn to dust over large areas of already parched land, then the carbon dioxide levels in the atmosphere will increase even more. “Plants need all of these elements, in the correct amounts, and at the right times, but increasing aridity will upset this balance, leading to a breakdown in essential soil processes,” said David Etheridge, of the University of New South Wales, one of the authors. “As the world’s population grows, people will increasingly rely on marginal lands – particularly drylands – for production of food, wood and biofuels. But these ecosystems will be severely affected by imbalances in the cycle of carbon, nitrogen and phosphorus.” – Climate News Network

FOR IMMEDIATE RELEASE A warming world carries many threats, and now scientists have discovered that a change in atmospheric conditions could have serious consequences for soil chemistry LONDON, 1 November – A warmer, drier world will be bad news for those people who already live on the edge. Higher temperatures will do more than evaporate the soil moisture: they will alter the natural soil chemistry as well. Manuel Delgado-Baquerizo of the Universidad Pablo de Olavide, in Seville, Spain, and fellow scientists report in Nature that they looked  at soil samples from 224 dryland ecosystem plots in every continent except Antarctica. Drylands matter: they account for more than 40% of the planet’s land surface and they support more than 38% of its population. Drylands add up, in the dusty language of science, to the largest “terrestrial biome” of all. And even though on average more warmth will mean more evaporation, and therefore more water vapour in the atmosphere and more precipitation in some of those zones that already have ample rainfall, the pattern could be different in the arid lands. All the calculations so far indicate that these drylands will increase in area, and become drier with time. Already 250 million people are trying to scrape an increasingly meagre living from lands which are degrading swiftly, either because they are turning to desert, or because they are overgrazed.

Hard on microbes

But to make things worse, climate scientists predict that between 2080 and 2099, soil moisture will decrease by between 5% and 15% worldwide. And that in turn could have a profound effect on the levels of carbon and nitrogen nutrients naturally in the topsoils. What keeps soils alive, and productive, is the compost or humus of leaf litter, animal dung, withered roots and other decaying vegetation in the first metre or so of topsoil: this in turn feeds an invisible army of tiny creatures that recycle the nutrient elements for the next generation of plant life. But these microbes also need water to thrive. The consortium of researchers predicted that as the soils got drier, biological activity would decrease, but geochemical processes would accelerate. That is, nutrients that depended on little living things in the soil would drain away, but other elements – phosphorus among them – would increase, because they would be winnowed from the rock by mechanical weathering or erosion. The research team tested this argument with samples from 16 countries, including the Negev desert in Israel, the woodlands of New South Wales in Australia, the Altiplano of Peru, and the Pampas lowlands of Argentina.

Balance upset

These regions could all expect from 100mm of rainfall a year to 800 mm; all soil samples were analysed in the same laboratory in Spain. And as predicted, they revealed an increasing imbalance: more phosphorus, less carbon and nitrogen as they became drier. Such a trend would actually feed back into global warming: ideally, more vigorous plant growth would absorb more carbon dioxide. But if vegetation wilts, and soils turn to dust over large areas of already parched land, then the carbon dioxide levels in the atmosphere will increase even more. “Plants need all of these elements, in the correct amounts, and at the right times, but increasing aridity will upset this balance, leading to a breakdown in essential soil processes,” said David Etheridge, of the University of New South Wales, one of the authors. “As the world’s population grows, people will increasingly rely on marginal lands – particularly drylands – for production of food, wood and biofuels. But these ecosystems will be severely affected by imbalances in the cycle of carbon, nitrogen and phosphorus.” – Climate News Network

Desert yields clues to species’ survival

FOR IMMEDIATE RELEASE Research into one of the world’s oldest and driest deserts has unearthed evidence of the evolutionary timeline for species that have avoided extinction by adapting to dramatic climate change LONDON, June 26 − Biodiversity’s response to global warming is difficult to predict, but new research shows that species in the distant past have adapted to, and colonised, new and increasingly arid desert zones during a period of dramatic change. The less encouraging finding from the University of Chile scientists who have studied geological evidence from the Atacama-Sechura desert region − one of the Earth’s oldest and driest deserts − is that this adaptation takes about six million years. Any wildlife response to dramatic climate change – and the kind predicted in the worst case scenario for the 21st century is certainly in the dramatic category − depends on a very large number of factors.

Barriers to movement

These include how fast plants or small animals can move to cooler zones south or north; what barriers – such as mountain ranges, lakes, cities, motorways or farms − there might be to movement; and, of course, whether the ecosystem that supports any particular species can move at the same rate. Researchers have repeatedly warned of mass extinction under conditions of climate change, but it has been much harder to calculate the rates at which species might adapt or evolve, and populations recover, in new habitats. However, there are lessons to be learned from the recent geological past − long before Homo sapiens began to create extra difficulties for the rest of creation. Climate scientists can date changes in global temperatures with reasonable accuracy, palaeontologists can identify and date fossils of characteristic climate zone species with some precision, and geneticists can measure the rate at which DNA has evolved to adapt to new environments. This last technique now delivers a good measure of evolutionary timelines. Pablo Guerrero and fellow researchers at the University of Chile’s Department of Ecological Sciences report in the Proceedings of the National Academy of Sciences that they used geological evidence to put dates to the rainfall history of the ancient Atacama-Sechura desert region of Chile and Peru and the DNA readings to measure the rates at which three different kinds of plant and one genus of lizard evolved to colonise the new habitat.

Huge time lags

They found that these groups of plants and animals made their homes in the desert only in the last 10 million years – a good 20 million years after the onset of aridity in the region. There were also huge lags – from 4 million to 14 million years − between the time these creatures moved into the desert region and when they colonised the hyper-arid places. These ultra-dry parts of the region developed about 8 million years ago, but the most diverse of the plant group moved in only two million years ago. “Similar evolutionary lag times may occur in other organisms and habitats, but these results are important in suggesting that many lineages may require very long time scales to adapt to modern desertification and climate change,” the scientists in Chile report. − Climate News Network        

FOR IMMEDIATE RELEASE Research into one of the world’s oldest and driest deserts has unearthed evidence of the evolutionary timeline for species that have avoided extinction by adapting to dramatic climate change LONDON, June 26 − Biodiversity’s response to global warming is difficult to predict, but new research shows that species in the distant past have adapted to, and colonised, new and increasingly arid desert zones during a period of dramatic change. The less encouraging finding from the University of Chile scientists who have studied geological evidence from the Atacama-Sechura desert region − one of the Earth’s oldest and driest deserts − is that this adaptation takes about six million years. Any wildlife response to dramatic climate change – and the kind predicted in the worst case scenario for the 21st century is certainly in the dramatic category − depends on a very large number of factors.

Barriers to movement

These include how fast plants or small animals can move to cooler zones south or north; what barriers – such as mountain ranges, lakes, cities, motorways or farms − there might be to movement; and, of course, whether the ecosystem that supports any particular species can move at the same rate. Researchers have repeatedly warned of mass extinction under conditions of climate change, but it has been much harder to calculate the rates at which species might adapt or evolve, and populations recover, in new habitats. However, there are lessons to be learned from the recent geological past − long before Homo sapiens began to create extra difficulties for the rest of creation. Climate scientists can date changes in global temperatures with reasonable accuracy, palaeontologists can identify and date fossils of characteristic climate zone species with some precision, and geneticists can measure the rate at which DNA has evolved to adapt to new environments. This last technique now delivers a good measure of evolutionary timelines. Pablo Guerrero and fellow researchers at the University of Chile’s Department of Ecological Sciences report in the Proceedings of the National Academy of Sciences that they used geological evidence to put dates to the rainfall history of the ancient Atacama-Sechura desert region of Chile and Peru and the DNA readings to measure the rates at which three different kinds of plant and one genus of lizard evolved to colonise the new habitat.

Huge time lags

They found that these groups of plants and animals made their homes in the desert only in the last 10 million years – a good 20 million years after the onset of aridity in the region. There were also huge lags – from 4 million to 14 million years − between the time these creatures moved into the desert region and when they colonised the hyper-arid places. These ultra-dry parts of the region developed about 8 million years ago, but the most diverse of the plant group moved in only two million years ago. “Similar evolutionary lag times may occur in other organisms and habitats, but these results are important in suggesting that many lineages may require very long time scales to adapt to modern desertification and climate change,” the scientists in Chile report. − Climate News Network        

Acid seas make corals feeble but they survive

FOR IMMEDIATE RELEASE Two important habitats for marine life, coral reefs and eelgrass meadows, will survive climate change but it will make them vulnerable. LONDON 17 June – Ocean acidification will make coral skeletons more feeble and coral reefs more vulnerable to battering by the seas – but it may not kill the corals, according to new research from the University of California, Santa Cruz. The Californian scientists report in the Proceedings of the National Academy of Sciences (PNAS) that they tested coral’s response to changes in future ocean chemistry not by experiments in a tank in a laboratory, but under real conditions – off Mexico’s Yucatan Peninsula where submarine springs naturally alter the chemistry of the surrounding sea water. “People have seen similar effects in laboratory experiments,” said Adina Paytan, of the university’s Institute of Marine Sciences. “We looked in places where corals are exposed to lower pH for their entire lifespan. The good news is that they don’t just die. They are able to grow and calcify, but they are not producing robust structures.” As carbon dioxide levels rise, falling rain becomes even more weakly acidic, and all rain eventually makes its way into the oceans, changing the water chemistry subtly. Storm waves By monitoring seawater chemistry near natural submarine springs, and by examining cores from colonies of an important Caribbean reef-building coral called Porites astreoides, the scientists were able to show that predicted future changes in water chemistry did have consequences for creatures that exploit that chemistry: it became more demanding for the coral animals to build up the blocks of calcium carbonate skeletons. As the skeletons become less dense, so they become more vulnerable to storm waves, and to coral predators. Corals are also vulnerable to temperature rise, and recent research has shown that corals can recover slowly from devastating spells of heat. Now it seems they can survive changes in ocean acidity. The question of course is whether reefs can survive both at the same time – and other stresses such as pollution and overfishing. Eelgrass meadows Meanwhile, far away to the north and across the Atlantic, Swedish researchers at the University of Gothenburg have been testing the effect of both rising temperatures and changes in sea chemistry on another important marine ecosystem: the eelgrass meadows. Christian Alsterberg reports in the PNAS that they raised the temperature in laboratory tanks containing eelgrass, while at the same time bubbling extra carbon dioxide through the water, to simulate the real changes predicted in the decades to come. The aim was to see how the plants, and the animals for which the plants form a natural habitat, responded. As water temperatures increased, for instance, so did the metabolism of many of the crustaceans that live in the eelgrass meadows. As a consequence, the animals consumed more algae, and grazed the meadows more efficiently. Benthic microalgae on the sediment of the meadows responded more vigorously. Overall, there seemed to be no great effect on the meadows. But that depended on the presence of crustaceans: without these small, algae-eating animals, the outcome could have been much worse. The research is just another piece in the vast jigsaw puzzle of climate science, in which small changes can have complex outcomes. “The experiment also taught us the importance of investigating climate change using several different approaches, in order to fully understand its effects and to predict future impacts,” said Alsterberg. – Climate News Network

FOR IMMEDIATE RELEASE Two important habitats for marine life, coral reefs and eelgrass meadows, will survive climate change but it will make them vulnerable. LONDON 17 June – Ocean acidification will make coral skeletons more feeble and coral reefs more vulnerable to battering by the seas – but it may not kill the corals, according to new research from the University of California, Santa Cruz. The Californian scientists report in the Proceedings of the National Academy of Sciences (PNAS) that they tested coral’s response to changes in future ocean chemistry not by experiments in a tank in a laboratory, but under real conditions – off Mexico’s Yucatan Peninsula where submarine springs naturally alter the chemistry of the surrounding sea water. “People have seen similar effects in laboratory experiments,” said Adina Paytan, of the university’s Institute of Marine Sciences. “We looked in places where corals are exposed to lower pH for their entire lifespan. The good news is that they don’t just die. They are able to grow and calcify, but they are not producing robust structures.” As carbon dioxide levels rise, falling rain becomes even more weakly acidic, and all rain eventually makes its way into the oceans, changing the water chemistry subtly. Storm waves By monitoring seawater chemistry near natural submarine springs, and by examining cores from colonies of an important Caribbean reef-building coral called Porites astreoides, the scientists were able to show that predicted future changes in water chemistry did have consequences for creatures that exploit that chemistry: it became more demanding for the coral animals to build up the blocks of calcium carbonate skeletons. As the skeletons become less dense, so they become more vulnerable to storm waves, and to coral predators. Corals are also vulnerable to temperature rise, and recent research has shown that corals can recover slowly from devastating spells of heat. Now it seems they can survive changes in ocean acidity. The question of course is whether reefs can survive both at the same time – and other stresses such as pollution and overfishing. Eelgrass meadows Meanwhile, far away to the north and across the Atlantic, Swedish researchers at the University of Gothenburg have been testing the effect of both rising temperatures and changes in sea chemistry on another important marine ecosystem: the eelgrass meadows. Christian Alsterberg reports in the PNAS that they raised the temperature in laboratory tanks containing eelgrass, while at the same time bubbling extra carbon dioxide through the water, to simulate the real changes predicted in the decades to come. The aim was to see how the plants, and the animals for which the plants form a natural habitat, responded. As water temperatures increased, for instance, so did the metabolism of many of the crustaceans that live in the eelgrass meadows. As a consequence, the animals consumed more algae, and grazed the meadows more efficiently. Benthic microalgae on the sediment of the meadows responded more vigorously. Overall, there seemed to be no great effect on the meadows. But that depended on the presence of crustaceans: without these small, algae-eating animals, the outcome could have been much worse. The research is just another piece in the vast jigsaw puzzle of climate science, in which small changes can have complex outcomes. “The experiment also taught us the importance of investigating climate change using several different approaches, in order to fully understand its effects and to predict future impacts,” said Alsterberg. – Climate News Network

Warming bad for life in freshwater lakes and rivers

For immediate release On both sides of the Atlantic scientists studying lakes have discovered they are warming – and this is bad news both for water quality and the fish. London, 14 June – The Alpine lakes of Austria are warming up. By 2050, their surface waters could be up to 3°C warmer, according to new research in the journal Hydrobiologia. Martin Dokulil of the Institute for Limnology at the University of Innsbruck studied data from nine lakes larger than 10km2. The largest, Bodensee or Lake Constance, touches Austria’s border with Germany and Switzerland to the west; 800 kms to the east, Neusiedler See borders Germany and Hungary. The nine lakes range from 254 to 1.8 metres maximum depth and they are vital to Austria’s tourist industry: they play powerful roles in the Alpine ecosystem and they are of course reservoirs of water. But the Alpine valleys are warming: between 1980 and 1999 the region warmed at three times the global average and by 2050 the median temperatures for the region could have risen by 3.5°C. The challenge has been to anticipate the impact of global warming on the lakes. “The predicted changes in surface water temperatures will affect the thermal characteristics of the lakes,” says Dr Dokulil. “Warmer water temperatures could lead to enhanced nutrient loads and affect water quality by promoting algal blooms and impairing the biological functions of aquatic organisms. “Significant increases in summer temperatures will affect the carbon cycling in the lakes, with potential consequences on atmospheric carbon dioxide levels and the Earth’s climate.”  Next, the fish The Austrian research so far is concerned only with freshwater temperatures. Peter Moyle, a biologist at the University of California Davis, has been more concerned with the freshwater fish that make their homes in, or migrate to, California’s rivers and lakes. He and colleagues report in the journal PLOS One – the Public Library of Science – that if current climate trends continue, then 82 per cent of California’s native fish could be extinct, and their native homes colonized by invasive species. The scientists looked at 121 native species and found that four fifths of them were likely to be driven to extinction or at least to very low numbers. These include prized sporting fish such as the Klamath River summer steelhead and other trout, the Central Valley Chinook salmon, the Central Coast coho salmon and many others that depend on cold water. “These fish are part of the endemic flora and fauna that makes California such a special place,” said Prof Moyle. “As we lose these fishes, we lose their environments and are much poorer for it.” – Climate News Network        

For immediate release On both sides of the Atlantic scientists studying lakes have discovered they are warming – and this is bad news both for water quality and the fish. London, 14 June – The Alpine lakes of Austria are warming up. By 2050, their surface waters could be up to 3°C warmer, according to new research in the journal Hydrobiologia. Martin Dokulil of the Institute for Limnology at the University of Innsbruck studied data from nine lakes larger than 10km2. The largest, Bodensee or Lake Constance, touches Austria’s border with Germany and Switzerland to the west; 800 kms to the east, Neusiedler See borders Germany and Hungary. The nine lakes range from 254 to 1.8 metres maximum depth and they are vital to Austria’s tourist industry: they play powerful roles in the Alpine ecosystem and they are of course reservoirs of water. But the Alpine valleys are warming: between 1980 and 1999 the region warmed at three times the global average and by 2050 the median temperatures for the region could have risen by 3.5°C. The challenge has been to anticipate the impact of global warming on the lakes. “The predicted changes in surface water temperatures will affect the thermal characteristics of the lakes,” says Dr Dokulil. “Warmer water temperatures could lead to enhanced nutrient loads and affect water quality by promoting algal blooms and impairing the biological functions of aquatic organisms. “Significant increases in summer temperatures will affect the carbon cycling in the lakes, with potential consequences on atmospheric carbon dioxide levels and the Earth’s climate.”  Next, the fish The Austrian research so far is concerned only with freshwater temperatures. Peter Moyle, a biologist at the University of California Davis, has been more concerned with the freshwater fish that make their homes in, or migrate to, California’s rivers and lakes. He and colleagues report in the journal PLOS One – the Public Library of Science – that if current climate trends continue, then 82 per cent of California’s native fish could be extinct, and their native homes colonized by invasive species. The scientists looked at 121 native species and found that four fifths of them were likely to be driven to extinction or at least to very low numbers. These include prized sporting fish such as the Klamath River summer steelhead and other trout, the Central Valley Chinook salmon, the Central Coast coho salmon and many others that depend on cold water. “These fish are part of the endemic flora and fauna that makes California such a special place,” said Prof Moyle. “As we lose these fishes, we lose their environments and are much poorer for it.” – Climate News Network        

Plenty Of Surprises As World Warms

 For immediate release Estimating how alterations in rainfall patterns will affect tree growth in different regions is a puzzling business LONDON, 4 June – Nobody knows for certain what climate change will bring but on the basis of the latest research by plant ecologists, one thing has been established: there will be surprises. Milena Holmgren of Wageningen University in the Netherlands and colleagues report in Nature Climate Change that they used satellite data to look at the patterns of change in tree cover in three tropical belts: Africa, Australia and South America. The chief conclusion is that changes in rainfall patterns from year to year were linked to lower tree cover in the rainforests of all three continents. In the dry tropics, however, the picture changed in puzzling ways. In South America, for instance, the higher overall variation in rainfall between years turned out to be a good thing, encouraging tree growth in the semi-arid regions. That confirmed other studies that had suggested that those unexpected episodes of heavy rainfall in normally arid areas provided a happy window of opportunity for trees to get a better hold. But in Australia, although extremes of rainfall in the desert and dry plains certainly had some effect on tree growth and regeneration, this was usually overwhelmed by the negative effects of extremely dry years. Meanwhile in the baking, dusty regions of tropical Africa, the procession of up-and-down rainfall levels seemed to make no great difference. “During extremely rainy years, there is massive tree germination and if these young seedlings grow fast enough to escape from herbivores, then woodlands can expand,” says Dr Holmgren. “With our analysis of satellite data, we can assess how general this response it. We found the positive effects of extremely rainy years is localised, and can be offset by certain conditions, as in Australia, by negative effects of extremely dry years.” Ecosystem changes This is not climate science as such, but rather another exploration of how the world works – and what, if anything, climate change will do for tropical tree cover. The scientists say their work is relevant to global climate change as warming could increase the frequency of extreme events: so as floods and droughts and heat waves blight the tropics, ecosystems could change in ways that might present problems for humanity – or a bonus. For instance, if trees do take hold in semi-arid grasslands, is that going to be a good thing for grazing livestock or wild herbivores? On the other hand, in those places where the woodland has perished – leaving eroded, dusty plains and valleys – sudden colossal downpours might just give trees a chance to regenerate, put down roots, provide some hospitality for the local biodiversity and perhaps even sequester a bit more carbon and lock it away in an increasingly fertile soil. But these remain possibilities, not predictions. “The overall effects of climate variability are puzzling,” says Dr Holmgren. – Climate News Network

 For immediate release Estimating how alterations in rainfall patterns will affect tree growth in different regions is a puzzling business LONDON, 4 June – Nobody knows for certain what climate change will bring but on the basis of the latest research by plant ecologists, one thing has been established: there will be surprises. Milena Holmgren of Wageningen University in the Netherlands and colleagues report in Nature Climate Change that they used satellite data to look at the patterns of change in tree cover in three tropical belts: Africa, Australia and South America. The chief conclusion is that changes in rainfall patterns from year to year were linked to lower tree cover in the rainforests of all three continents. In the dry tropics, however, the picture changed in puzzling ways. In South America, for instance, the higher overall variation in rainfall between years turned out to be a good thing, encouraging tree growth in the semi-arid regions. That confirmed other studies that had suggested that those unexpected episodes of heavy rainfall in normally arid areas provided a happy window of opportunity for trees to get a better hold. But in Australia, although extremes of rainfall in the desert and dry plains certainly had some effect on tree growth and regeneration, this was usually overwhelmed by the negative effects of extremely dry years. Meanwhile in the baking, dusty regions of tropical Africa, the procession of up-and-down rainfall levels seemed to make no great difference. “During extremely rainy years, there is massive tree germination and if these young seedlings grow fast enough to escape from herbivores, then woodlands can expand,” says Dr Holmgren. “With our analysis of satellite data, we can assess how general this response it. We found the positive effects of extremely rainy years is localised, and can be offset by certain conditions, as in Australia, by negative effects of extremely dry years.” Ecosystem changes This is not climate science as such, but rather another exploration of how the world works – and what, if anything, climate change will do for tropical tree cover. The scientists say their work is relevant to global climate change as warming could increase the frequency of extreme events: so as floods and droughts and heat waves blight the tropics, ecosystems could change in ways that might present problems for humanity – or a bonus. For instance, if trees do take hold in semi-arid grasslands, is that going to be a good thing for grazing livestock or wild herbivores? On the other hand, in those places where the woodland has perished – leaving eroded, dusty plains and valleys – sudden colossal downpours might just give trees a chance to regenerate, put down roots, provide some hospitality for the local biodiversity and perhaps even sequester a bit more carbon and lock it away in an increasingly fertile soil. But these remain possibilities, not predictions. “The overall effects of climate variability are puzzling,” says Dr Holmgren. – Climate News Network