PlanetArk 28 Oct 10;
Scientists are struggling to get a full picture of the variety of wildlife species around the globe as climate change, human exploitation and pollution threaten "mass extinctions," a series of studies published on Wednesday showed.
The 16 studies in a special issue of the Philosophical Transactions of the Royal Society in London said science had an incomplete record of species from animals to plants and microbes at a time when they may be dying out faster than ever before.
Such concerns have led the United Nations to declare 2010 its International Year of Biodiversity, and governments are trying to agree new 2020 conservation targets at a two-week conference in the Japanese city of Nagoya, which ends Friday.
"There are very strong indications that the current rate of species extinctions far exceeds anything in the fossil record," said a summarizing paper, titled "Biological diversity in a changing world."
"We still have a very incomplete record of the biological diversity of the planet," the paper added, saying quantitative tools were needed to understand large-scale changes to the planet.
One area of particular concern was tropical forests, which have seen their area roughly halved since the start of the last century.
Scientists still do not understand the extent to which logging destroyed wider networks of wildlife species, and whether they could re-colonize areas which were allowed to re-grow, called "secondary" forest.
Another worry was oceans, where climate change was causing fish populations to shift, and in the case of tropical areas would destroy some habitats altogether as these became too warm.
"To date, warming within the world's oceans has been variable in magnitude though unequivocal in scope," said a paper on the impact on fisheries, called "Transitional states in marine fisheries: adapting to predicted global change."
"Fisheries in some areas are expected to collapse in response to repeated acute disturbance and increasing temperature," the paper said.
