Jerusalem, January 23, 2011 -- Global warming is already affecting the earth in a variety of ways that demand our attention. Now, research carried out at the Hebrew University of Jerusalem indicates that many tree species might become extinct due to climate change if no action is taken in time.
According to the research, trees which 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, head of the Alexander Silberman Institute of Life Science at the Hebrew University; his student, Nir Horvitz; and researchers from abroad.
Climate changes, which can be sensed already today and which are expected to continue in the next 50 years, 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.
Furthermore, 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.
These questions were examined in this study for the first time. 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 effects of increased seed production and earlier
|Contact: Jerry Barach|
The Hebrew University of Jerusalem