and the threat of infection could be reduced by moving fruit trees, where the bats roost, away from pig farms,
a team led by ecologist Robin Chazdon of the University of Connecticut in Storrs has found that 90%of tree species from the original landscape can also be found in secondary forest.
Chazdon and her colleagues assessed tree biodiversity changes in northeastern Costa rica by surveying 18 hectares of preserved old-growth forest and 11 hectares of secondary forest,
When they looked for trees with a diameter greater than 10 centimetres, they found only 59%of the old-growth tree species in the regrown areas.
But when they extended their search to seedlings and saplings the number rose to 90%.
%We needed to start looking at the little guys, says Chazdon. But the future is bleak for many secondary forests,
trees are having trouble regenerating, possibly because large birds that act as seed dispersers have gone extinct in the area.
but the technology is advanced not yet enough to distinguish between old and regrown trees. Gregory Asner, an ecologist at the Carnegie Institution of Washington who is based in Stanford, California,
however, the forests have increasingly been being replaced by row upon row of rubber trees; from the air, they look like gigantic mazes hemming in the conservation centre.
whether rubber trees could be grown at such high latitudes. The researchers discovered a tropical paradise
and palm trees for biofuels many worry that appropriate regulation and controls may come too late.
and select rubber trees that can survive at higher elevations. They are also trying to raise output by making rubber trees mature faster than the current seven years.
The large-scale rubber cultivation has taken a heavy toll on the local environment, says Zhu Hua, an ecologist at the XTBG.
But the winter fog is becoming less pronounced as rubber trees take over the landscape, says Zhu.
4. More water is lost also from the spaces between rubber trees, which grow farther apart than rainforest vegetation.
they are less likely to go around chopping down trees, says Hu, who runs the Xishuangbanna arm of the project.
The vegetation in the region, dominated by bushes and tall eucalyptus trees, burns extremely well when dry.
Most trees and tall vegetation can survive normal bushfires, and smaller, more frequent fires reduce the risk of a catastrophic blaze.
and after the drought revealed that forest patches subjected to a 100-milimetre decrease in rainfall released on average 5. 3 tonnes of carbon per hectare as trees in the area died.
Measuring tree growth is notoriously difficult, not least because tropical observation networks are pitifully few, particularly in Africa.
Problems related to plot selection, comparability and converting tree-diameter measurements to carbon content have led to an intense debate about the size and fate of the tropical (and global) terrestrial carbon sink.
Dying trees may exacerbate climate change: Nature Newsforestry experts have warned again that climate change could transform forests from sinks to sources of carbon.
The mountain pine beetle has devastated the forests of western Canada. The outbreak currently covers 14 million hectares roughly 3. 5 times the size of Switzerland,
The mountain pine beetle outbreak and the climate signal associated with it is the canary in the coal mine about future disturbances.
Stuart Pimm and his colleagues at the Nicholas School of the Environment at Duke university in Durham, North carolina, have found that fewer fires are being lit to clear trees inside reserves in the Brazilian Amazon than outside them.
Fires hot enough to kill trees are bright enough to be seen from space at night.
The studies encompass the pines and maples of eastern forests in Massachusetts and North carolina, the spruce and fir of northern Minnesota,
but it's difficult to warm stands of relatively large trees, says ecologist Scott Bridgham, of the University of Oregon in Eugene.
For now, the technology available limits such projects to seedlings and young trees on relatively small plots of land.
an ecologist at the University of Georgia in Athens. The most important determinant of where a species can grow is where the juvenile trees can grow
Nature Newsfamily trees for pandemic influenza have revealed that components of deadly flu viruses probably lurk in humans
Meanwhile, Amgen, of Thousand Oaks, California, has received more positive news for its new-mode-of-action osteoporosis treatment, denosumab.
of which more than 10-30%is covered by tree canopy. Trees must also have the potential to reach a minimum height of 2-5 metres.
Countries participating in the UNFCCC can choose how they want to define a forest from within those ranges.
with more than 30%canopy cover and a minimum tree height of 5 metres. By contrast, Ghana defines a forest as an area of land greater than 0. 1 hectare,
with more than 15%canopy cover and a minimum tree height of 2 metres. But a report1 in the journal Conservation Letters, says that the UNFCCC has set the proportion of land that must be covered by tree canopy too low.
Nophea Sasaki, a forest ecologist at Harvard university, and an author of the study, says that woodland could be degraded severely
Sasaki says that loggers tend to target the bigger, more mature tree species, which hold the most carbon.
In a case study of an evergreen forest in Cambodia, Sasaki and his co-author Francis Putz from the University of Florida in Gainsville use inventory data for plots of trees with trunks wider than 5 centimetres to estimate that the forest
Of this, 71.4 tonnes is in trees that have trunks wider than 45 centimetres the trees that loggers are most likely to target.
So if all these larger trees were harvested, the carbon stock would be depleted by almost 40,
%the minimum tree height should be 5 metres and that natural forests should be differentiated from plantations.
degradation is evaluated through on-the-ground studies that assess what types of tree species are growing
so that landowners don't need to begin cutting down trees again when the payments stop. Moutinho says the programme could be scaled up to 10,000 families in the Par ¡
To explore this, they set up nets every evening for a week around fruit trees in a remote region of southern Mexico where wrinkle-faced bats had been reported to be present.
Nature Newscanadian researchers have decoded the DNA of the tree-killing fungus found in the mouths of mountain pine beetles,
and pine tree species should help forest managers design better pest-control tactics, the authors say.
It's really getting to a systems-level understanding of the mountain pine beetle epidemic, says study co-author JÃ rg Bohlmann, a chemical ecologist at the University of British columbia in Vancouver, Canada,
Mountain pine beetles (Dendroctonus ponderosae) have eaten their way through vast swathes of western North american pine forests,
which stops the production of a protective toxic resin released by the tree and allows the beetles to continue to infest.
For the other two species the beetle and the tree the researchers are concentrating mainly on expressed gene sequences, fragments of the complete DNA sequence, rather than the genomes in their entirety.
The lodgepole pine (Pinus contorta) and jack pine (Pinus banksiana) are still at a much earlier stage of sequencing.
and say which population of trees is interacting with which population of fungus and which population of beetles,
pinpointed the gene responsible for staining the pine wood blue and created a knockout strain that does not produce any pigment.
which have started already to jump host species from lodgepole pine, which is found only west of the Rockies, to jack pine,
which stretches east across the entire continent. We might be able to tweak the system to reduce the beetle populations
which had young trees, which could skew the conclusions, says Bart Muys, a forest ecologist at the University of Leuven in Belgium.
More trees are cleared then for agriculture, meaning fewer trees can absorb the water from the rains.
Massive floods have hit the provinces of Chaco and Salta regions that have seen particularly high rates of deforestation.
The Economics of Ecosystems and Biodiversity (TEEB) study pointed to the ample financial returns of investment in protecting natural areas such as mangroves, tropical forests and grasslands.
which was set up by the late chocolate and coffee magnate Klaus Jacobs. The award, which will be presented on 3 december, must fund research.
Planting trees can shift water flow: Nature Newsplanting trees, which can significantly help to reduce atmospheric carbon dioxide,
nevertheless comes with potentially damaging side effects. According to two new studies, planting forests in areas that currently don't have trees a process called afforestation can reduce the local availability of water.
One key measure of water flow is'base flow, 'the proportion of a stream or river not attributable to direct run off from precipitation or melting snow.
With their deep roots and tall canopies, trees absorb and transpire more water than do grasses,
as water can escape from the tree roots and travel through the rocks. Jobb ¡gy presented his team's results last month at the World Forestry Congress in Buenos aires. A second study presented at the conference,
As the trees get larger, the effect will be somewhat greater, says Skaggs. The differences between Jobb ¡
gy's and Skaggs's figures are mainly due to differences in the number of trees per hectare in the two studies greater in Jobb ¡
gy's basins and the trees'age. In C Â rdoba, the studied areas were afforested in the 1970s
whereas Skaggs and his team planted their trees in 2003. Besides reducing base flow, afforestation can affect how water filters through the ecosystem.
Tree roots help to filter water into the soil, thus slowing the rate at which water levels rise after rain.
at least for his study areas, the ideal balance between afforestation and water needs is for one-quarter of the river basin to be planted with between 400 and 500 trees per hectare.
Choosing tree species wisely might help, Binkley and Jobb ¡gy suggest, as different species use water at different rates.
Whereas fast-growing evergreen pines consume large amounts of water, deciduous trees such as poplar and walnut use less, especially in winter.
Also, planting only some portions of the watershed might achieve the balance of providing wood products for the people without the impact on the basin's water balance
because their food shrubs and trees versus grasses carries out different types of photosynthesis. The team characterized the humans'isotope ratios by taking advantage of a fluke of history,
although such flooding did occur the Nazca brought on their own demise by logging trees to make way for farmland.
For much of the older portion of the record, the pollen came from riparian trees, like huarango,
when the Nazca cut down the trees they destroyed the root system that had been anchoring the landscape.
Nature News Liberia's caterpillar plague Panic struck Liberia in early 2009, after a plague of caterpillars struck villages around the country, munching trees
In fact it turned out to be Achaea catocaloides, a less threatening caterpillar that feeds mostly on the Dahoma tree.
Apart from the initial destruction of a few tree crops like cocoa, coffee and plantain, Achaea did not pose any threat to food crops like rice,
Arctic trees will make things warmer: Nature Newschalk up another piece of dire news for the Arctic in a globally warmed future.
Higher surface temperatures in recent decades are already making it easier for trees to grow farther north.
Fung's team ran a computer model that simulated trees moving into a swathe of bare land a region more than twice the size of Alaska at latitudes north of 60 degrees.
as a result of new tree and shrub growth, the landscape warmed by at least 1 Â C. In another twist,
records of ancient Arctic pollen suggest that deciduous trees colonize the landscape before evergreen trees.
And transpiration in deciduous trees is greater than that in evergreens, which means that they release more moisture as water vapour,
and other scientists to estimate how much carbon is locked within trees, vegetation and soils on a given patch of land rather than relying on rough averages that are calculated across a forest.
are like trees. Like any animal or plant, they are made out of carbon. And whales are so big they each store a lot of carbon,
He compares it to planting trees. In a forest, trees remove carbon dioxide from the atmosphere
and accumulate that as biomass. Whales take carbon out of the system through their food,
is like cutting down trees for firewood. You're taking whales out of the population
So syrup carbon-13 values are approaching the average 108 value that maple trees and most plants should have,
which the fungus trades nutrients with oak-tree roots. The T. melanosporum genome also reveals that the fungus reproduces sexually more often than researchers thought.
when inoculating oak trees, and to genetically fingerprint the truffles to be sure that they are not from the same family.
Shellfish could supplant tree-ring climate data: Nature Newsoxygen isotopes in clamshells may provide the most detailed record yet of global climate change,
One can envision a tree-ringlike continuous history, given a lot more effort. If he can find the funding,
Tree rings map 700 years of Asian monsoons: Nature Newstree-ring data from more than 300 sites in Asia have allowed scientists to piece together a year-by-year history of the region's monsoon rains as far back as 1300 AD.
In fact, says tree-ring expert Edward Cook, the models are poor enough that they don't even agree on
The problem, says Cook who is director of the Tree-Ring Laboratory at Columbia University's Lamont-Doherty Earth Observatory in Palisades, New york,
The data were compiled from tree-ring chronologies showing the year-to-year growth of ancient trees at 327 sites.
by necessity, clustered in regions where there are old trees, the rest of the map can be filled in by statistical analyses,
These analyses used tree-ring data from recent years, comparing them to existing weather data to find correlations with the older data
And by extending climate records back in time, the Asian tree-ring data, like similar studies in North america, have revealed past droughts that were much longer
In a paper published last month in the Proceedings of the National Academy of Sciences, tree-ring specialist Brendan Buckley, one of Cook's co-authors who is also at the Lamont-Doherty Earth Observatory,
plants and animals suggesting that the species'habitat was likely to have been a more open savannah with some trees rather than woods;
but that the specimens came from a strip of trees along a waterway through a savannah1.
harvesting old-growth trees and replacing them with seeds obtained from warmer climes can produce trees that will better withstand temperature increases,
These included projects on marine tourism mangrove restoration and agroforestry. But more often, the team found, projects had little or no economic benefit for the poorest people.
A 2009 analysis of ground plots4 found decreased growth and increased tree death from the 2005 drought,
researchers observed a 30%reduction in tree growth and a doubling in tree death over the course of 7 years.
Using a combination of satellite images and ground-based tree counts the report estimated that an unusual cluster of powerful thunderstorms in January of that year knocked down more than half a billion trees.
Those results do not necessarily undercut the drought research, which took place on plots unaffected by the storms.
when felled trees rot or are burned. The decline in illegal logging may have kept some 1. 2-14.6 billion tonnes of carbon dioxide locked up in trees over the last decade.
But the problem is solved by no means, the report says. Illegal logging is the first step in a larger process that often ends in complete deforestation
to look for oil among mangrove trees. A few kilometres from the village, the team found patches of what looked like highly weathered oil.
where they were once so abundant that local fishermen say they could chop off a mangrove branch
but that more productive ecosystems such as mangrove swamps or salt marshes the closest analogue to mangroves in the northern Gulf retain oil indefinitely.
as she saw that the goats were destroying the pine forests. In the beginning, the villagers wanted to kill us,
'Another allegation revolved around the handling of contentious tree-ring-width data used as a temperature proxy in a graph that contributed to the Fourth Assessment Report (AR4) of the Intergovernmental Panel on Climate Change (IPCC)
The width of tree-rings fail to closely track direct records of temperature beyond around the 1960s.
CRU scientists did not include this divergent tree-ring data from later years, instead splicing in direct temperature measurements that show a sharp temperature rise.
Had the tree-ring data been left in, it would not have implied that recent temperatures have been decreasing,
The committee also concluded that the scientists did not actively select certain tree-ring data in an attempt to bias the graph presented in the IPCC report.
Ross Mckitrick, an environmental economist at the University of Guelph in Ontario, Canada, argues the review missed the point of criticisms regarding the deletion of tree-ring data after the 1960s.
India has been busy planting trees including nonnative eucalyptus and acacia, to provide timber and fuel wood and in some cases to earn money from selling carbon credits under the Clean Development Mechanism established in 2001 as part of the Kyoto Protocol.
The country now ranks second globally in terms of total land area under plantation. Laurance says that much of India's claimed growth in forest cover has come from plantations,
because replanting native forests with nonnative trees damages local biodiversity, says Neil Burgess, a conservation biologist at the University of Copenhagen.
Most plantations of nonnative trees have very low biological value. They are only good to store carbon,
This distinction between native and nonnative trees is important for an accurate picture of the state of the world's forests,
But the Indian Remote Sensing satellites used by the FSI have a much higher resolution up to 23.5 square metres per pixel so the agency has the means to distinguish native forests from plantations of nonnative trees.
But he warns that not all the trees planted each year reach maturity and show up in satellite imagery.
Most are sparked by lightning in areas forested with fire-tolerant trees, which can withstand the worst of a fire, such as pine (Pinus).
Such fires are often beneficial to the functioning of the ecosystem, and forests usually regrow quickly after them.
and in places populated by trees that are not fire tolerant, such as birch (Betula). They are also reaching gardens
but it will take a long time, particularly for the slower-growing trees such as spruce (Picea).
Most of the radioactive particles are in the soil rather than in the flammable leaf litter and trees,
or seed-bearing plants including conifers and cycads, are the most at-risk group of plants,
with more than 75%of cycad species currently threatened with extinction. Habitat loss, resulting from the conversion of natural habitats for agriculture and livestock grazing
is the biggest threat to plants'survival, the study concludes. Existing indicators of biodiversity such as the Red List of Threatened Species of the International Union for Conservation of Nature (IUCN) focus mainly on vertebrates,
Harris says he is not surprised that the study found cycads to be endangered the most group.
That in turn would allow aspen trees munched into submission by the elk to begin growing back in those areas.
Tree rings and fenced-off experimental areas revealed that aspen growth didn't track well with wolf presence or absence.
which destroyed trees, impacted the livelihoods of fishermen and others who are dependent on the river and presented scientists with
but ground data provides clear evidence of biomass loss and an increase in tree deaths.
A recent analysis in the Proceedings of the National Academy of Sciences4 builds on this by suggesting that drought conditions could spur leaf loss and new leaf budding while simultaneously leading to a rise in tree deaths.
The tree shows relationships between the languages over time. Two languages with many differences would be placed on distant branches,
just as two species with the most genetic divergence would sit at opposite ends of a phylogenetic tree.
and superimposed that information onto the tips of the tree. Working back through the branches,
but to work out the phylogenetic tree. And once that's worked out, you can use that tree to study in this case political evolution.
So the only question would be'are languages a good way to work out relationships between societies?'
and modelled the timing of leaf-bud burst in 22 North american tree species throughout the twenty-first century3.
the cacao tree, whose beans yield chocolate, and the woodland strawberry. Earlier this year, a team backed by food giant Mars unveiled a preliminary sequence of the cacao tree Theobroma cacao.
Now a team partly supported by rival chocolate company Hershey has become the first to get a genome of the valuable plant into a peer-reviewed journal1.
or a moth's almost perfect mimicry of tree bark. In some snails, however, it's simply down to a poor fit with a snake's jaw.
Nature Newsas Malaysia prepares to convert around 7, 000 hectares of forest into an oil-palm plantation,
and replanted with oil palms. We are covering such a wide variety of questions says Rob Ewers, an ecologist at Imperial College London and the project's scientific director.
Other projects have focused mainly on a single issue such as trees or biodiversity. For instance, the project will look at which animal species survive in a forest as the level of logging intensifies until the land is converted fully into an oil-palm plantation.
Researchers will also investigate how wide the riparian zone the interface between land and rivers needs to be
and decided to convert the forest into an oil-palm plantation to bring in extra income, says Ewers.
and manage oil-palm plantations to minimize the environmental impacts. We want to use the data to optimally design future forest clearance for agricultural income and biodiversity.
which the oil palm will be planted. Tim Killeen, an ecologist with Conservation International, a not-for-profit environmental group, says that he is glad to see that someone is doing this study.
But the EPA has ruled that Spruce 1 Mine in the Appalachian mountains of West virginia presented major environmental and water-quality concerns,
The screwpine Pandanus tectorius (pictured), for example, has 294 synonyms. Researchers at the Royal Botanic Gardens, Kew, UK,
Nature Newsan international effort to protect coastal wetlands by assigning them carbon credits kicked off last week in Paris. The aim is to do for some wetland plants mangroves, seagrasses and salt marshes
-what carbon credits have done for trees. Wetland plants and forests act as carbon sinks, locking away substantial amounts of carbon absorbed from the atmosphere.
Mangroves and salt-marsh vegetation similarly accumulate carbon and when they decompose their carbon is locked away in watery, peaty sediments for millennia.
Between 1980 and 2005, nearly 35,000 square kilometres of mangroves were cleared so that coastal land could be used for agriculture, aquaculture and beach resorts.
Stephen Crooks, climate change programme manager at the environmental consultancy ESA PWA in San francisco, California, estimates that emissions from drained mangroves and salt marshes total half a billion tonnes
Data from Landsat satellites revealed the true extent of mangroves only last year. The survey found that in 2000,
mangroves covered 137,760 square kilometres in tropical and subtropical regions3, some 12%smaller than the previous estimate from the United nations. Some scientists argue that despite their ecological importance,
is useful to palaeontologists because of the way that it differs in shape between tree climbers and land walkers.
For the tree-dwelling chimpanzee, the fourth metatarsal lies flatter against the ground, and the middle of the foot is mobile.
This flat-footed structure grants chimpanzees tremendous flexibility and allows them to grasp branches in trees.
The discovery shows that A. afarensis was not dividing its time between trees and open land.
I'm sure they went into trees sometimes but they would not have been able to do this much better than you or
At Laetoli, Tanzania, some hominins walked across a bed of wet volcanic ash 3. 6 million years ago.
The Canadian Boreal Forest Agreement, a deal between the forestry industry and environmental groups, aims to set aside nearly 30 million hectares of northern wilderness and subject a further 42 million to strict tree
Horn's own research has shown an involvement for fish in distributing fig tree seeds in Costa Rica3.
The decision in question is the return of cattle to portions of the 646,000-hectare park, a landscape of deep ravines, high plateaux and snow gum trees.
Almost two-thirds of species, including many birds, frogs, butterflies, trees and grassland flowers, breed or bloom earlier.
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