Forests make heatwaves ‘initially warmer’


During heatwaves forests reduce their evaporation, causing the atmosphere to warm up even more, say researchers.

During extremely long periods of heat, however, this reduction enables the forests to continue their evaporation for longer, so the net effect is ultimately one of cooling in relation to the surroundings, explained a team of scientists led by Ryan Teuling from Wageningen University in the Netherlands.

Writing in the journal Nature Geoscience, Dr Teuling worked on the investigation in collaboration with climate researchers from a number of European countries.

The study was prompted by recent heatwaves in Europe, which had raised interest in questions about the influence of land use on temperatures and climate.

Up to now, scientists had assumed that a lack of precipitation during heatwaves automatically led to a reduction in evaporation.

That reduction was thought to be less for forests, because trees, with their deeper root systems, have more water available to them. Examination of the precise role of land use, however, has been largely neglected up to now.

The study found large differences in evaporation strategies during heat waves. Grasslands evaporate more at higher temperatures and stop only when no more water is available.

Forests, in contrast, respond to higher temperatures by evaporating less, which leaves more water at their disposal.

During brief heatwaves, therefore, the greatest warming is found above forests, but during prolonged heat waves the increased evaporation of grasslands ends up causing a shortage of water.

This can lead to exceptionally high temperatures, such as those measured in France in the summer of 2003.

This mechanism might also offer an explanation for the unusually high temperatures near Moscow this summer, the researchers suggest.

In these types of extreme situations, forests in fact have a cooling effect on the climate.

The research was done on the basis of observations made above forests and grasslands in Europe by an extensive network of flux towers. For areas without towers, satellite data were used.

Source: Wageningen University press release

Date: 06/09/2010

Illegal logging continues to plague Madagascar’s rainforest parks


Despite government assurances that it would crack down on the rosewood trade, illegal logging continues in Madagascar’s rainforest parks, according to new information provided by sources on the ground and reported in Wildmadagascar.com.

The sources report logging in three parks: Mananara, Makira, and Masoala. All three are known for their high levels of biodiversity, including endangered lemurs.

Rosewood logs are being transported to Tamatave (Toamasina), Madagascar’s main port, despite a national moratorium on logging and export of precious hardwoods. Most rosewood ends up going to China, where it is in high demand for furniture.

The Malagasy sources report that local law enforcement—the new Brigade Mixte Forestière established to reduce logging—is impeded the Forest Ministry, which has failed to grant them the right to use search warrants on private property.

The sources also claim that rosewood confiscated by authorities is being stolen from official stockpiles.

Illegal logging exploded last year in the aftermath of a military coup that displaced the democratically-elected, but increasingly autocratic president, Marc Ravalomanana.

National parks, especially in the North-East of the country, were ransacked by loggers employed by timber barons who traditionally capitalize on political instability or natural disasters to replenish timber stocks and traffic ill-gotten wood.

Madagascar is now ruled by a “transition authority” that has so far shown little inclination to hold free and fair elections and has been be slow to address the logging crisis despite pressure from the international community.

Source: Wildmadagascar.com

Date:06/09/2010

US wolf re-introduction still leaves aspens quaking


The re-introduction of wolves in a US National Park in the mid-1990s is not helping quaking aspens (Populus tremuloides) to become re-established, as many researchers hoped.

In a study published in the journal Ecology showed that the population of wolves in Yellowstone Park was not deterring elks from eating young trees and saplings.

It was assumed that the presence of wolves would create a “landscape of fear”, resulting in no-go areas for elks.

Researchers writing in the Ecological Society of America’s (ESA) journal said that the aspens were not regenerating well in the park as a result of the elk eating the young trees.

However, they added that the conventional wisdom suggested that as the wolves were predators of the elk, it was thought that the elk would eventually learn to avoid high-risk areas in which the wolves were found.

This would then allow plants in those areas – such as aspen – to grow big enough without being eaten and killed by the elk. And in the long-term, the thinking went, the habitat would be restored.

In this latest study, lead author Matthew Kauffman – a US Geological Survey scientist – suggested the findings showed that claims of an ecosystem-wide recovery of aspen were premature.

“This study not only confirms that elk are responsible for the decline of aspen in Yellowstone beginning in the 1890s, but also that none of the aspen groves studied after wolf restoration appear to be regenerating, even in areas risky to elk,” Dr Kauffman explained.

Because the “landscape of fear” idea did not appear to be benefiting aspen, the team concluded that if the Northern Range elk population did not continue to decline (their numbers are 40% of what they were before wolves), many of Yellowstone’s aspen stands were unlikely to recover.

“A landscape-level aspen recovery is likely only to occur if wolves, in combination with other predators and climate factors, further reduce the elk population,” observed Dr Kauffman.

The paper, Are wolves saving Yellowstone’s aspen? A landscape-level test of a behaviorally mediated trophic cascade, has been published online in Ecology. The authors of the paper are: Matthew Kauffman (USGS), Jedediah Brodie (University of Montana) and Erik Jules (Humboldt State University).

Source: ESA press release

Date: 01/09/2010

International forestry researchers look to future


The Center for International Forestry Research (CIFOR) has released a plan of work for 2011-2013, as a part of its 2008-2018 Strategy.

The organisation – established in 1999 – sets out its mission statement as advancing “human well-being, environmental conservation, and equity by conducting research to inform policies and practices that affect forests in developing countries”.

The updated plan provides more details on CIFOR’s six projects, and what outcomes they hope to achieve:

  • Enhancing the role of forests in climate mitigation
  • Enhancing the role of forests in adaptation to climate change
  • Improving livelihoods through smallholder and community forestry
  • Managing trade-offs between conservation and development at landscape scales
  • Managing impacts of globalized trade and investment on forests and forest communities
  • Sustainable management of tropical production forests

The 145-page work plan, Medium term plan for 2011-13, is available as a free-to-download pdf (size: 1.5MB)

Source: Climate-L.org

Date: 25/08/2010

Africa push for ‘great tree wall’


African leaders are meeting in Chad to push the idea of planting a tree belt across Africa from Senegal in the west to Djibouti in the east, reports the BBC News website.

The Great Green Wall project is backed by the African Union and is aimed at halting the advancing Sahara Desert.

The belt would be 15km (nine miles) wide and 7,775km (4,831 miles) long.

The initiative, conceived five years ago, has not started because of a lack of funding and some experts worry it would not be maintained properly.

The BBC’s Tidiane Sy in Senegal says the initiative has the full backing of Senegalese President Abdoulaye Wade, who is in Chad with 10 other heads of state to discuss desertification.

His government has created the website dedicated to the Great Green Wall. But our reporter says many other leaders seem ready to forget the project.

At the Copenhagen Climate Change summit last year, for instance, the Senegalese delegation made a presentation on the project.

It is envisaged that the belt would go through 11 countries from east to west.

The trees should be “drought-adapted species”, preferably native to the areas planted, the Great Green Wall website says, listing 37 suitable species.

The initiative says it hopes the trees will slow soil erosion; slow wind speeds and help rain water filter into the ground, to stop the desert from growing.

It also says a richer soil content will help communities across the Sahel who depend on land for grazing and agriculture.

Senegal says it has spent about $2m (£1.35m) on it and communities are being encouraged to plant trees.

The BBC’s former Chad correspondent Celeste Hicks says older people in N’Djamena – where the conference is being held – talk anecdotally about how the capital city has become a dustbowl over the last 20 years as the Sahara Desert has encroached southwards.

The country has made efforts to plant a green belt of trees around the capital, and tens of thousands of young trees are being grown in nurseries on the outskirts of the city, she says.

But so far little has been done to transplant these trees to the northern desert areas to become part of the Great Green Wall.

Source: BBC News website

Date: 17/06/2010

Boost for Indonesian ‘ecosystem restoration’ forest


Indonesia’s forests  received a boost when the nation’s government announced plans to double the size of the country’s first forest for “ecosystem restoration”, according to a joint press release issued by the RSPB.

It says that Indonesian Forest Minister Zulkifli Hasan has announced that he will expand the 52,000 hectare concession held by Burung Indonesia, the RSPB (UK) and BirdLife International in central Sumatra to a total area of 98,000 hectares.

According to the RSPB, the restoration area now equals two-thirds the size of greater London and is greater than the size of Singapore.

The bird conservation group welcomed the news, adding that other applications for ‘forest restoration’ licences are being submitted to the nation’s forestry ministry.

In 2009, the ministry is reported to have received as many applications for forest restoration licences as it did for logging concessions.

Applications for forest restoration totalled a further two million hectares, and are now being assessed.

The 98,000 hectares where the minister announced he would grant “ecosystem restoration” is within Harapan Rainforest, one of the last remaining areas of dry lowland Sumatran forest and is one of the most threatened rainforests in the world.

It is home to a host of rare animal and plant species, including the critically endangered Sumatran tiger (Panthera tigris sumatrae), of which fewer than 300 remain in the wild.

It supports an amazing 55 mammal species, including the globally-threatened Asian elephant (Elephas maximus sumatranus) and Malayan tapir (Tapirus indicus), as well as the world’s rarest stork – the Storm’s stork (Ciconia stormi) – and a rich diversity of other wildlife.

An initial licence of 52,000 hectares was granted to the environmental consortium in 2008, allowing them to protect, nurture and restore the forest in a former logging concession.

Illegal logging has been significantly decreased and forest fires, which once released significant carbon dioxide emissions, have been all but stamped out. Not only is the forest an important carbon store, but the tree planting programme in Harapan Rainforest is capturing more carbon from the atmosphere.

Botanic experts from the Royal Botanic Gardens, Kew in the UK have identified a plant growing in the forest, Emblemantha urnulata B. C. Stone, that is unique to the area and had only been recorded twice before.

Agus B. Utomo, the Executive Director of Burung Indonesia, said: “The Ministry of Forestry had the foresight to create a new form of forest management in 2004 with the ‘ecosystem restoration’ licence.

“We’re delighted that ecosystem restoration is now an integral part of forest management strategies in Indonesia. As a result, Burung Indonesia is already planning to expand our portfolio of ecosystem restoration concessions.”

Source : RSPB press release

Date: 18/06/2010

Indonesia ‘failing on pledge to reduce forest fires’


The Indonesian government failed to live up to its promises to reduce fires across the tropical nation last year, reports Mongabay.com.Take Cover library picture

It quotes The Jakarta Post as saying that the nation’s 2009 State Environment Report revealed a 59% increase in the number of fire hotspots from 19,192 in 2008 to 32,416 last year.

Officials are reported as saying that land clearing was the primary cause because, unlike temperature forests, intact rainforests rarely burn naturally.

“Illegal land clearing with fires by local people in Kalimantan and Sumatra is still rampant,” Heddy Mukna, deputy assistant for forest and land management at the Environment Ministry told the Post.

The state of Kalimantan on the island of Borneo saw fires triple in some areas from 2008 to 2009.

Haze blanketed much of the island last year during the “burning season”.

In 2007, the Indonesian government announced plan to cut forest fires in half to mitigate climate change from 35,279 fires in 2006.

The government has since revised that reduction from 50% to just 20%.

Indonesia is the third largest emitter of greenhouse gases in the world behind China and the US.

An estimated 80% of the nation’s 2.3 billion tonnes of greenhouse gas emissions is from rainforest and peatland destruction.

Source: Mongabay.com

Date: 13/06/2010

UK elms – ‘not out of the woods yet’


Colin Tudge, the author of The Secret Life of Trees, is invited by the UK’s Telegraph newspaper to give his reaction to efforts to breed a Dutch elm disease-resistant species.

Library image from Take CoverIt’s an interesting read as he gives his reaction to this battle with nature, so here it is:

Could the English elm, so sadly laid low by Dutch elm disease, make a comeback? Paul King, who breeds trees at Raine in Essex, is on the case. Nearly 25 years ago he acquired cuttings from a few mature trees. He has now multiplied the tissues to produce a whole new generation of young elms that seem to be resistant (and are on sale for £120 apiece). Scientists at the Forestry Commission’s research centre in Surrey welcome his initiative – they are on the case, too – but are cautious. Resistance, they point out, is a tricky business.

The English elm, Ulmus procera, is probably not a “true” native – Britain has only 39 “truly” native trees – and was most likely introduced by Neolithic farmers from south-east Europe, via Spain. But it is an honorary citizen, treasured for its usefulness and its looks, favourite of landscape painters, notably of Constable; a tree of open woodland but just as happy in hedgerows where, if it was left alone, it flourished by the tens of millions. In the West Country it was known as “the Wiltshire weed”.

The first sign of trouble came in 1910 when the fungus Ophiostoma ulmi, a distant and degenerate cousin of the truffle, started killing trees in mainland Europe. It acquired its name, Dutch elm disease, in 1921 because it was first properly researched in Holland. It arrived in Britain by 1927 and looked very nasty. Happily, the disease died down by the Forties, after killing 10 to 40 per cent of our elms. Dr Tom Pearce of the Forestry Commission predicted, in 1960, that such a thing should not happen again – unless, he added, “the fungus completely changes its present trend of behaviour”.

Which it duly did. A new, closely related species of Ophiostoma appeared in North America – Ophiostoma novo-ulmi. It arrived in Britain in 1967 on imported logs, and throughout the Seventies and into the Eighties it killed about 25 million out of about 30 million elms, including most of the particular English species, Ulmus procera.

Dutch elm disease has all the biological attributes needed to be thoroughly nasty. It is one of the many “wilt diseases” of trees, which spread through the vessels of the xylem and block them. The spores are carried passively with wonderful efficiency in the sap, through the whole tree, and spread via the roots of separate trees that are often joined underground. The spores don’t live long once the tree has died and so should die out as their host succumbs – but they have a trump card: they are carried from tree to tree and from forest to forest by flying bark beetles of the genus Scolytus.

There is some innate resistance among the world’s many species of elm. The Ophiostoma fungus probably arose in Asia, so the Asian elms have evolved in its presence – and have developed considerable resistance. Breeding programmes are afoot in Europe to introduce genes from Asian species into European types by various means – and may yet succeed. Meanwhile, as Paul King has found, even within susceptible species, such as Ulmus procera, there will usually be some resistant strains. If they can be bred, perhaps we will have a new resistant strain.

So why the caution? Well, for one thing, it depends what the tree is really resistant to: the fungus or its insect vector? Paul King’s new trees are probably not resistant to the fungus itself, but are simply less palatable to the beetle. Of course, the fungus can’t usually infest the tree without the beetles – but it surely would be better to be specifically equipped with genes that would protect it even if beetles did get in.

The sad tale of Britain’s elms parallels that of the American chestnut, Castanea dentata – with some intriguing contrasts. For the American Indians and for the first immigrant Europeans, the American chestnut was a wonder tree. Its nuts were a food staple – and supported 40 million wild turkeys for good measure – and its trunks provided timber. There were so many that a squirrel could travel from chestnut to chestnut from Maine to Georgia without setting foot on the ground, or so the story went.

But the overconfident forestry “improvers” of the 19th century were still not content. They began to import Asian species with bigger nuts, to crossbreed. Inevitably, the newcomers came with their own diseases. And the American chestnuts, beset by novel pathogens, succumbed. By the end of the Twenties, the American chestnut, once perhaps the commonest North American broadleaf, was all but gone.

Again, through too much zeal, the Americans felled great swathes of chestnuts to create a firewall against the spread of infection. This failed to contain the disease – but it did, so some biologists suggest, remove the myriad genetic variations from among the wild trees, which might have included some that would have conferred resistance.

By leaving our own beleaguered elms to live on in the hedges, and nurturing the few survivors, as Paul King and others have been doing, we may avoid that final fate. (In truth, the American chestnut might not quite be dead. At least, George W Bush planted one outside the White House on Arbor Day in 2005 – but it is a hybrid: 15 per cent of its genes are from resistant Asian species. It is a sad relic, like an exhumed dodo).

Overall, the message is mixed. We could see the heroic efforts of a few growers and scientists as a triumph of human ingenuity over natural adversity – the continuing tale of “man’s conquest of nature”. Or we could see this endeavour as a desperate, last-ditch attempt to ward off the consequences of our own folly. For these are tales of hubris. We thought we could do what we liked in the name of commerce. But actually, life is more complicated than we ever supposed – and in the end, it is beyond our ken. Cause and effect relationships in nature are non-linear, which means it is intrinsically impossible to predict the outcome, beyond saying it won’t be good.

Source: Telegraph newspaper

Date: 09/06/2010

Study finds 25 news beetle species on Turkey’s oaks


Twenty-five hitherto unknown species of beetle have been found on the Turkey’s oak trees, according to a study by Swedish researchers.

Take Cover library picture“Most of them would disappear if the trees were to be cut down, and the risk is great”, says project leader Nicklas Jansson, beetle ecologist at Linkoping University (LiU) in Sweden.

In Turkey, there are 18 species of the oak family, and Dr Jansson and his research team spent five years collecting beetles from oak trees in four large pastures in the south of the country.

They said the study areas – 1,200-1,500 metres above sea level – were important for sheep and goat farming, but were now threatened by felling to make way for productive forest management.

They warned that as with all felling there is a major risk that some species become extinct since the oak dwelling beetles stay so faithful to their biotope.

“Some of the species seem to have a very low motivation to leave and find a new oak,” Dr Jansson observed.

Most of the newly discovered beetles belong to the Elateridae and Tenobrionidae families and have been identified by some 20 specialists across Europe.

The results were presented at a conference on oak ecology in Isparta, Turkey.

The researchers identified a number of factors that could be responsible for the greater diversity of beetles:

  • a climate that allowed species to hibernate during the Ice Ages
  • the topography which creates many barriers in the form of mountain ranges and other obstacles to the mixing of species
  • the geographic location as a bridge between Asia and Europe.

In a follow-up project, the research team planned to compare the oak fauna of seven countries, including Israel, Turkey, Italy, France, the UK  and Sweden.

The oaks in the Turkish pastures are pollarded. Shepherd people prune the trees in July and during the dry season use the leaves as feed for sheep and goats while the branches become fuel.

As a result of pollarding, many of the oaks were hollow and contain wood mould, a very rich compost of decomposed wood, fungi, excrement and remains of dead animals.

“I hope that in finding new and unique species we will get the Turkish forestry authorities to open their eyes to their oak treasures and to begin conservation work in the most valuable areas,” Dr Jansson explained.

Source: AlphaGalileo press release

Date: 01/06/2010

Oak disease ‘threatens British landscape’


The continuing spread of a deadly disease that affects the UK’s native oak trees is causing concern among tree professionals and conservation groups.

Take Cover library photoThe BBC’s environment reporter Mark Kinver writes that Acute Oak Decline (AOD), caused by a bacterial infection, can kill an infected tree in just a few years.

Some tree experts are comparing AOD to Dutch elm disease, which killed millions of trees throughout the UK during the 1970-80s.

They said extra funds for more research into the disease were urgently needed.

Although AOD has been confirmed in 55 cases, the number of trees displaying symptoms was steadily increasing, delegates at the Royal Forestry Society’s (RFS) annual conference were told.

The disease affects the UK’s two native species of oak – sessile and pedunculate. To date, there have been no confirmed cases in other species of oaks found in Britain, such as Turkey and red oaks.

‘Extensive bleeding’

Information from Forest Research, the scientific department of the UK Forestry Commission, says the new disease affects oaks more than 50 years old.

Symptoms are “extensive stem bleeding” in which dark fluid seeps from small cracks in the bark and runs down the tree trunk.

In early stages of the disease, the health of a tree’s canopy does not appear to be affected, but it may become thinner as the tree succumbs to AOD.

On its website, Forest Research says: “The incidence of AOD in Britain is unquantified at this stage, but estimates put the figure at a few thousand affected trees.

“The condition appears to be most prevalent in the Midlands and investigations to determine the extent of the disorder are under way.”

A spokesman told BBC News: “Forest Research pathologists have isolated a previously unidentified bacterium they believe is highly likely to be playing a key role in the Acute Oak Decline observed in Leicestershire and elsewhere.

“However, the full cause of the condition is thought likely to be complex, involving a number of factors besides the bacterium. A research report is currently awaiting peer review.”

‘Major threat’

Tree organisations are calling for more funding to be made available to allow researchers to better understand the full impact of the disease.

John Jackson, the organiser of the RFS’s conference, said: “Urgent action is not an option – it’s a necessity.”

Hilary Allison, policy director for the Woodland Trust, added: “The impact of the loss of an iconic tree both from our countryside and towns would be catastrophic, and therefore has the capacity to be a major threat to the UK’s oak woods.”

“I have never seen anything like it,” said Peter Goodwin, co-founder of Woodland Heritage.

“Its spread over the last two years has been quite alarming.”

Mr Goodwin told BBC News that very little was known about the virulent bacteria responsible for the disease.

“We’ve never had a bacterium that is capable of doing what this one is doing.”

He suggested that people were possibly the main way in which the disease was spread from tree to tree, but added that “natural vectors” – such as squirrels, birds and insects – could also play a role.

“I think this is the worrying thing, we all want to know what are the vectors that is spreading it. Is it airborne? We just don’t know.”

Forest Research advises people working in affected areas to take appropriate measures to limit the chances of AOD being carried to new sites.

“The most important thing we can do in this and other cases is to research and understand the causes so that we can provide appropriate management advice for tree owners and woodland managers,” the spokesman added.

“It is also important that we remain vigilant against accidentally importing new and damaging pests and diseases from outside Great Britain.”

Source: BBC News website

Date: 28/04/10

Forest fire emissions ‘poisoning Arctic environment’


Forest fires and straw and stubble burning in North America and Eastern Europe are leading to record-high concentrations of the environmental toxin PCB over the Arctic island of Svalbard, a report warns.

Take Cover library imageOver the past decades, persistent organic pollutants (POPs) have been found in large concentrations in Arctic areas.

These substances accumulate in living organisms and are enriched throughout the food chain.

Polychlorinated biphenyl (PCB) is one of the most important environmental toxins of this type.

“We wanted to draw attention to the causes of the environmental impact in the Arctic and trace the sources of the problem,” said Sabine Eckhardt, a researcher at the Norwegian Institute for Air Research (NILU).

When biomass from trees and dead grass and leaves catches fire, it releases both PCB and other environmental toxins and creates yet another source of PCB emissions.

In 2004 and 2006, big fires ravaged these areas. About 5.8m hectares of coniferous forest burned down in North America, while Eastern Europe experienced extensive emissions from agriculture due to straw and stubble burning.

Several weeks later, the researchers found record-high values of PCB in the atmosphere above Svalbard.

“As far as we know, this is the first study that shows a connection between the burning of biomass and PCB concentrations in the atmosphere far away,” said Sabine Eckhardt.

“With a climate that is constantly changing, we expect the extent of such fires to increase.

“In such case, it also means that the fires may represent an increasing environmental problem in the Arctic.

“That in turn will reduce the effect of the international agreements that aim to reduce emissions of these environmental toxins,’ said Ms Eckhardt.

PCB is a group of synthetically-produced persistent toxic compounds., and can be stored in the fatty parts of the organism and accumulates in the food chain.

Humans, fatty fish and carnivores (such as polar bears) can therefore accumulate concentrations in their bodies that are so high that they are poisoned.

As the primary emissions of organic environmental toxins are reduced, the researchers believe that fires caused by climate change will become more important.

They point to the fact that there has been little focus on the significance of burning biomass, and the potential consequences of this for the Arctic environment.

“For the first time, we have proved that burning biomass is also an important source of persistent organic pollutants in polar areas,” Ms Eckhardt observed.

“This can be of great importance to international agreements that aim to protect the environment in Arctic areas.”

Source: The Research Council of Norway

Date: 31/05/2010

US Forest Services announces plan to save at risk forests


US Forest Service chief Gail Kimbell announced $50 million in grants to permanently protect 24 working forests across 21 States, as part of the  Forest Legacy Program, a USDA press release said.

The programme is designed to permanently protects important private forestland threatened by conversion.

“The Forest Legacy Program conserves open space, which allows us to respond to climate change, improves water quality and flows and connects children to nature,” said Agriculture Secretary Tom Vilsack.

“The strength of the Forest Legacy Program is the co-operation between States, partners and private landowners, all working together to protect environmentally and economically important forests that are threatened by conversion.”

Examples of 2009 projects include: forest essential for wildlife and recreation in Maine; pine ecosystem critical for threatened and endangered species in Arkansas and working forests that support rural jobs in Oregon.

The Forest Legacy Program promotes voluntary land conservation by operating on the principle of “willing buyer, willing seller”.

Private forest landowners are facing increasing real estate prices, property taxes and development pressure, which result in conversion of forests to other land uses.

The Forest Legacy Program focuses on conserving working forests – those that provide clean water, forest products, fish and wildlife habitat and recreational opportunities.

Most Forest Legacy Program projects are conserved through conservation easements, allowing landowners to keep their forestlands while protecting them from future development.

Source: USDA press release

Date: 18/05/2009

Forest Research draws up canker plan


Forest Research is to develop guidance on managing and drawing up controlling strategies for the bleeding canker tree blight, reports Horticulture Week.

“This disease has rapidly become widespread throughout Britain over the past five years,” said a representative for the research arm of the Forestry Commission.

Bleeding canker of horse chestnut was caused by the bacterium Pseudomonas syringae pv aesculi (Psa), but until recently it had only been reported in India in 1980, he said.

“It has now proved to be highly mobile and exceptionally virulent to European horse chestnut, Aesculus hippocastanum.”

Researchers were looking to provide an accurate diagnosis of the pathogen and underpin management strategies to combat the disease.

“A technique called real-time polymerase chain reaction has been developed and is being used to detect the levels of Psa on infected trees and their surroundings.”

Previously little was known about what natural resistance horse chestnut populations may have had to Psa.

“But evidence indicates that even in heavily affected locations some trees remain healthy and symptom-free.

“Disease-free horse chestnuts have been propagated and will be tested for disease resistance in inoculation trials and compared against other disease-prone individuals.

“This research will ultimately guide management and mitigation strategies. Molecular techniques developed will also be applicable to the study of other important tree diseases.”

Source: Horticulture Week

Date: 07/05/2009

Wild fruit trees face extinction


Scientists have warned that the wild ancestors of common domestic fruit trees are in danger of becoming extinct, reports the BBC’s Victoria Gill.

Researchers have published a “red list” of threatened species that grow in the forests of Central Asia.

These disease-resistant and climate-tolerant fruit trees could play a role in our future food security.

But in the last 50 years, about 90% of the forests have been destroyed, according to conservation charity, Fauna & Flora International.

The Red List of Central Asia identifies 44 tree species in Kyrgyzstan, Kazakhstan, Uzbekistan, Turkmenistan and Tajikistan as under threat from extinction.

It cites over-exploitation and human development as among the main threats to the region’s forests, which are home to more than 300 wild fruit and nut species including apple, plum, cherry, apricot and walnut.

Antonia Eastwood, the lead author of the research, described the region as a “unique global hotspot of diversity”.

“A lot of these species are only found in this area,” she told BBC News. “It’s very mountainous and dry, so many of these species have a great deal of tolerance to cold and drought.

“A lot of our domestic fruit supply comes from a very narrow genetic base,” she continued.

“Given the threats posed to food supplies by disease and the changing climate, we may need to go back to these species and include them in breeding programmes.”

Kazakhstan and Kyrgyzstan are thought to be the ancestral homes of familiar favourites such as Red Delicious and Golden Delicious.

The US Department of Agriculture has already sponsored expeditions to Kazakhstan, during which scientists have collected samples with the aim of expanding the genetic diversity of farm-grown apples.

This type of genetic foraging, Dr Eastwood explained, allows domestic lines to be crossed with wild strains, producing varieties more resistant to diseases such as apple scab, a fungus that can devastate crops.

“But these countries lack the resources to conserve their valuable trees,” added Dr Eastwood.

This year, as part of the the UK Darwin Initiative, Fauna & Flora International is working with scientists in Kyrgyzstan to carry out research on threatened trees and develop methods to harvest the fruit sustainably.

The organisation is training local scientists and involving communities in the planning and managing of their own forests.

Source: BBC News website

Date: 07/05/2009

Pine voles blamed for US oak declines


Scientists trying to understand why oaks are starting to disappear from North American forests may need to look just below the surface to find some answers, says a Purdue University press release.

Researcher Robert Swihart found that pine voles, small rodents that live underground, prefer oak roots to those of other common woodland seedlings.

The study identifies the rodents as a possible factor leading to high oak mortality rates that are threatening the resource base of the hardwood industry.

“You see a lot of mature oaks, but you don’t see a lot of oaks in the understory beneath the canopy,” observed Dr Swihart.

“If you don’t see them there, you won’t see mature oaks in 20 to 30 years.

“We are facing a period in our history that could lead to a great crash in oak availability.”

Dr Swihart offered pine voles a selection of tree roots to eat in the laboratory, and they overwhelmingly gravitated toward oak roots.

Voles caused more than twice as much damage to white oak roots than northern red oak and black cherry, and more than six times more damage to white oak than black walnuts.

The study showed that the voles snubbed yellow poplar roots altogether.

“Either the oak roots were much more nutritious and had higher energy content, or they contained fewer toxins, or some combination of those factors,” he explained.

“Those are the main reasons an animal will choose one food item over another.”

His findings have been published in the Canadian Journal of Zoology.

Source: Purdue University press release

Date: 03/03/2009

Tree planting in the driest place on Earth


The southern coast of Peru is one of the driest places on Earth. Why would anyone choose this parched location to re-plant a forest, asks the BBC’s John Walton.

The strip of desert between the Andean mountains and the Pacific Ocean has an annual average rainfall as low as 1.5mm.

By way of comparison, London enjoys around 650mm a year.

It’s not an obvious place to choose if you’re looking for somewhere to plant trees, but for restoration ecologist Oliver Whaley the harsh environment of the northern fringes of the Atacama desert is part of the point.

By helping to restore the shrinking native forests, the aim is to benefit local people and wildlife, prevent soil erosion, and help alleviate climate change.

“If we can get trees established here, and learn how to do it with as little water as possible, then it is a model for the rest of the world,” he says.

While the plight of the world’s rainforests are well known, the same cannot be said of tropical dry forests. These less biodiverse, but equally remarkable forests, face threats every bit as severe as their better known cousins.

The Atacama dry forest “is really an ecosystem on its last legs,” says Mr Whaley, of London’s Kew Gardens – an internationally renowned botanical research institution.

The tree under threat is the huarango, Prosopis limensis, found only in the Ica region of Peru.

In this parched landscape, the hardy huarango is no stranger to thirst. Although rain seldom falls, it is able to capture moisture from other sources – trapping fog on its leaves, directing the water downwards towards its roots. The roots themselves are among the longest of any plant – 50m to 80m – and seek out underground water sources that flow from the Andes.

The huarango is also a valuable source of food and fuel, and a keystone of the local ecosystem. Whaley estimates that when he arrived in Peru, just 1% of the original local forest habitat remained – much of it consumed in charcoal production.

The problems facing dry forest habitat are not unique to Peru. Restoration expert James Aronson says, in general, these are more critically endangered than wet tropical forests, in respect of the total percentage already lost.

Mr Aronson, who heads the Restoration Ecology Group in the Centre for Functional and Evolutionary Ecology in Montpellier, France, adds there are more than 1,000 species of tree that grow in desert areas.

“In many desert areas of the world there used to be enough trees to constitute to a real canopy – not in the sense of an English forest, where the forest is everywhere you look – [in deserts] they were restricted to areas where there was sufficient water.”

With so little forest in existence, conservation, on its own, would not be enough to preserve the trees, leaving restoration as the only option.

It’s a situation made more complicated by the global recession.

Some local agro-industries growing asparagus, grapes and oranges for foreign markets are laying off workers. With hard times on the way, Mr Whaley worries that what little vegetation remains may be used for firewood.

Whatever his project’s success, Mr Whaley is certain that the future of the tree rests firmly in the hands of the local people. They are encouraged to help with planting, and tree nurseries and seedbanks have been sent up in communities and schools.

“We are not going to Peru saying we are going to reforest the whole of the coast. We are developing a model that we can replicate and hopefully we can get that to be so interesting, or fun, or useful that it’s contagious.”

Hence the idea of an annual huarango festival, started in 2006 and held in April. The festival is a chance to celebrate the tree and the ecosystem it helps support. But it is also about food. The fruit of the tree can be used to make syrup, similar to molasses.

“Fill people’s tummies,” says Mr Whaley. “Where do you get social science and biodiversity overlapping? In the stomach. That is the best place to do it.”

The project has already had some successes, with a reserve set up in Tunga (see map, below), and more planned.

“We are at the beginning of habitat restoration – it’s only a science that’s been around for a couple of decades. Particularly in arid areas, we are only just learning how to do it.

“If I am able to come back in 500 years, then I would know if it has been a success. I will never know in my lifetime if its been a success.”

Source: BBC News website

Date: 20/04/2009

Key role of forests ‘may be lost’


Forests’ role as massive carbon sinks is “at risk of being lost entirely”, the BBC’s Mark Kinver has reported top forestry scientists as warning.

The International Union of Forest Research Organizations (IUFRO) says forests are under increasing degrees of stress as a result of climate change.

Forests could release vast amounts of carbon if temperatures rise 2.5C (4.5F) above pre-industrial levels, it adds.

The findings will be presented at the UN Forum on Forests, which begins on Monday in New York.

Compiled by 35 leading forestry scientists, the report provides what is described as the first global assessment of the ability of forests to adapt to climate change.

“We normally think of forests as putting the brakes on global warming,” observed Professor Risto Seppala from the Finnish Forest Research Institute, who chaired the report’s expert panel.

“But over the next few decades, damage induced by climate change could cause forests to release huge quantities of carbon and create a situation in which they do more to accelerate warming than to slow it down.”

The scientists hope that the report, called Adaption of Forests and People to Climate Change – A Global Assessment, will help inform climate negotiators.

The international climate debate has focused primarily on emissions from deforestation, but the researchers say their analysis shows that attention must also be paid to the impacts of climate change on forests.

While deforestation is responsible for about 20% of greenhouse gas emissions from human activities, forests currently absorb more carbon than they emit.

But the problem is that the balance could shift as the planet warms, the report concludes, and the sequestration service provided by the forest biomes “could be lost entirely if the Earth heats up by 2.5C or more”.

The assessment says higher temperatures – along with prolonged droughts, more pest invasions, and other environmental stresses – would trigger considerable forest destruction and degradation.

This could create a dangerous feedback loop, it adds, in which damage to forests from climate change would increase global carbon emissions that then exacerbate global warming.

The report’s key findings include:

  • Droughts are projected to become more intense and frequent in subtropical and southern temperate forests
  • Commercial timber plantations are set to become unviable in some areas, but more productive in others
  • Climate change could result in “deepening poverty, deteriorating public health, and social conflict” among African forest-dependent communities

The IUFRO assessment will be considered by delegates at the eighth session of the UN Forum on Forests, which has the objective of promoting the “management, conservation and sustainable development of all types of forest”.

Co-author Professor Andreas Fischlin from the Swiss Federal Institute of Technology commented: “Even if adaption measures are fully implemented, unmitigated climate change would – during the course of the current century – exceed the adaptive capacity of many forests.

“The fact remains that the only way to ensure that forests do not suffer unprecedented harm is to achieve large reductions in greenhouse gas emissions.”

Source: BBC News website

Date: 18/04/2009

Wildlife flee Kenyan forest fires


Hundreds of thousands of flamingos and other wildlife are at risk after five forest fires erupted in Kenya on Saturday, say wildlife officials.

The BBC News website reports that police say they suspect some of the still-raging blazes were started by communities to make space for farmland.

The fires have had an adverse effect on the Masai Mara and in Tanzania on the Serengeti national park, officials say.

Other wildlife reserves are under threat, including Lake Nakuru, which is home to almost a million flamingos.

According to the Kenya Wildlife Service (KWS), all the rivers that drain from south-western Kenya’s Mau forest into the lake have dried drastically.

Nearly 60 species of wildlife, including white rhino, depend on the lake.

By Sunday an estimated 200 hectares (500 acres) of woodland had been razed in Mau – East Africa’s largest indigenous forest.

KWS communications manager Paul Udoto told the BBC: “We now have to pump water from underground bore holes to shallow pans to water the animals in the park otherwise they will all die. This is costing us a lot of money.”

Members of communities opposed to government plans to move them out of the Mau forest are suspected, say police, and several people have been arrested, accused of arson.

Another blaze nearby has destroyed about a quarter of the 52 sq km (20 square miles) Mount Longonot National Park, an extinct volcano in Kenya’s Rift Valley, said officials.

Zebras, buffaloes, antelopes, gazelles and giraffes have fled the fires, crossing roads and residential areas to reach safety, said witnesses.

But some wildlife experts said snakes and smaller animals, like rabbits and mongooses, may not have managed to escape.

Kenya is suffering a drought this year that has contributed to hunger the government says is affecting 10 million people.

Source: BBC News website

Date: 23/03/2009

Quarter of PNG’s rainforests ‘lost to logging’


Nearly one quarter of Papua New Guinea’s rainforests were damaged or destroyed between 1972 and 2002, Mongabay.com reports.

Researchers, writing in the journal Biotopica, said the results – published in a report last June – show that Papua New Guinea is losing forests at a much faster rate than previously believed.

Over the 30-year study period, 15% of the nation’s tropical forests were cleared and a further 8.8% were degraded through logging.

“Our analysis does not support the theory that PNG’s forests have escaped the rapid changes recorded in other tropical regions,” the authors wrote.

“We conclude that rapid and substantial forest change has occurred in Papua New Guinea.”

Deforestation and forest degradation in Papua New Guinea are primarily driven by logging, followed by clearing for subsistence agriculture.

Since 2002 (a period not covered in the study), reports suggest that conversion of forest for industrial agriculture, especially oil palm plantations, has increased.

The study is based on comparisons between a land-cover map from 1972 and a land-cover map created from nationwide high-resolution satellite imagery recorded in 2002.

The authors found that most deforestation occurred in commercially accessible forest, where forest loss ranged from 1.1 to 3.4% each year.

Overall deforestation was 0.8 to 1.8% per year, higher than reported by the UN Food and Agriculture Organization (FAO), but lower than the rate of deforestation on neighboring islands, including Borneo and Sumatra.

Papua New Guinea’s primary forest cover fell from 33.23 million hectares to 25.33 million hectares during the 30-year period.

In the same period, almost 93 million hectares of forest were degraded by logging.

Lead author Phil Shearman, director of the University of Papua New Guinea’s Remote Sensing Centre, said that without incentives to keep forest standing, Papua New Guinea would continue to lose its forests.

“Forests in Papua New Guinea are being logged repeatedly and wastefully with little regard for the environmental consequences and with at least the passive complicity of government authorities,” Dr Shearman said.

He noted that nearly half of the country’s 8.7 million hectares of forest accessible to mechanised logging have been allocated to the commercial logging industry.

But he added that there may be hope because Papua New Guinea had become a leader in the push by tropical nations to seek compensation from industrialised countries for conserving forests as a giant store of carbon.

The mechanism known as REDD (Reducing Emissions from Deforestation and Degradation) could potentially provide billions of dollars for conservation, sustainable development and poverty alleviation.

“The government could make a significant contribution to global efforts to combat climate change,” observed Dr Shearman.

“It is in its own interest to do so, as this nation is particularly susceptible to negative effects due to loss of the forest cover.”

UN studies have show that coastal communities in Papua New Guinea are particularly at risk from climate change.
Source: Mongabay.com

Date: 23/02/2009

Deforestation in Vietnam continues to rise


Deforestation has increased by 55% during the past year in Vietnam’s Dak Nong province, reports the Vietnam News Agency.

A report in Mongabay.com said that at least 440 hectares (1,100 acres) of tropical forest were illegally logged in the central highland province, and protected areas were also being targeted.

Forest officials attribute the increase to high commodity, especially corn, prices, which encourages the conversion of forest for cropland.

Another factor, the website reports, is the  lack of staff and resources among companies that have leased forest concessions.

Vietnam has one of the world’s highest rates of primary forest loss.

Between 1990 and 2005, the country lost 78% of its old-growth forests. Much of these were replaced with industrial plantations, with overall forest cover increasing by more than a third since 1990.

Plantations are biologically impoverished relative to natural forests. They also store less carbon.

Source: Mongabay.com

Date: 18/02/2009

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