Tree species greatly at risk from climate change
By ANITuesday, January 25, 2011
WASHINGTON - Scientists at Hebrew University of Jerusalem have indicated that many tree species might become extinct due to climate change if no action is taken in time.
Their study suggested that trees that disperse their seeds by wind, such as pines and maples, will be unable to spread at a pace that can cope with expected climate changes.
The research, which focused on the ecological consequences of expected changes in the climate and the environment on tree spread, was conducted by Prof. Ran Nathan of Hebrew University; his student, Nir Horvitz; and researchers from abroad.
Climate changes include the increase of carbon dioxide concentration in the air and a reduction of surface wind speed in many areas.
On the basis of earlier work, elevated concentration of carbon dioxide is expected to cause trees to produce many more seeds and to reach maturity earlier than under current conditions, hence speeding up their spread.
On the other hand, the weakening of wind speed in certain areas should reduce spread rate of these trees. The balance between these opposing forces remained unknown.
Also it was unclear whether even the projected increase in wind speed in certain areas, together with the higher seed production and earlier maturation, will result in a fast enough spread of trees in order to be sufficient to match the climate changes.
All these questions were examined in this study for the first time. And surprisingly, the results show that changes in wind speed, either the projected increase or decrease, have negligible effects on the rate of wind-driven spread of these species.
The study showed that the faster spread predicted for these trees in the future will be much slower than the expected poleward shift of climate (temperature) ranges. Consequently, these tree species might not be able to withstand the climate change.
Consequently, these tree species might not be able to withstand the climate change.
The new research has been published in the journal Ecology Letters. (ANI)