New research conducted at the Hebrew University of Jerusalem show that many tree species may be unable to shift with the changing climates, and could face extinction if manmade intervention is not made.
The research looked at trees which dispersed their seeds via the wind, which include trees like pines and maples, and looked at what the predicted changes in wind speed would have on the spread of trees, as well as the effect made by increasing temperatures on seed formation.
The result of the study showed that increases or decreases in wind speed will have a mostly negligible effect on the spread of seeds and their ability to match pace with the shift of their favoured habitat. What will be the important thing is increased speed and earlier maturation of trees which is likely to take place as a result of warmer temperatures.
However, the researchers showed that the faster spread that has been predicted for trees which rely on the wind to move their seeds is much slower than will be necessary to keep up with the theorized poleward shift of climate and temperature ranges.
As a result, if the trees cannot shift in time, they will die out.
“Our research indicates that the natural wind-driven spread of many species of trees will increase, but will occur at a significantly lower pace than that which will be required to cope with the changes in surface temperature,” said Professor Ran Nathan, head of the Alexander Silberman Institute of Life Science at the Hebrew University.
“This will raise extinction risk of many tree populations because they will not be able to track the shift in their natural habitats which currently supply them with favorable conditions for establishment and reproduction. As a result, the composition of different tree species in future forests is expected to change and their areas might be reduced, the goods and services that these forests provide for man might be harmed, and wide-ranging steps will have to be taken to ensure seed dispersal in a controlled, directed manner.”
The model used to create the predictions which gave Nathan and his colleagues their data is the first of its kind to use projected changes in biological and environmental factors to gauge the impact on tree spread in future environments.
“It is important for those responsible for forest management in many parts of the world to understand that nature alone will not do the job,” said Nathan. “Human action will be required to ensure in a controlled manner the minimization of unexpected detrimental byproducts, and that those trees which are very important for global ecological processes will not become extinct. These forests are important in many ways to man, including the supply of wood, the safeguarding of water quality, and the provision of recreation and tourism facilities.”