Long term implications of climate change and air pollution on forest ecosystems. (Progress report of the IUFRO task force 'forest, climate and air pollution')
1993
Schlaepfer, R. (ed.)
The main objective of the IUFRO Task Force "Forest, Climate Change and Air Pollution" is to evaluate and synthesise information on the state of science in these fields and to address possible effects of climate change and air pollution on forest ecosystems. The question posed by the Task Force Committee to the Contributing Board members in 1992 was "What are the direct and indirect effects and the long-term risks of climate change and air pollution on forest ecosystems?" The responses which were limited to two pages illustrate the wide range of topics, hypotheses, methods and primary results, but also the gaps and the uncertainties in our current knowledge of the subject. General circulation models conclude that we are facing a global climate change induced by an increase of atmospheric greenhouse gas concentrations leading to a rise in the global mean temperature and changes in the precipitation pattern. The consequences of potential global climate change on forest ecosystems are uncertain. The ability of forests to migrate or to adapt to any climate change will depend on the magnitude and the rate of the change in climate. The evidence for widespread, irreversible declines in forest health because of air pollution is very limited. When rigorous criteria are applied to establishing a cause-effect relationship between air pollution and forest condition, air pollution cannot at present be seen as a major factor affecting forest trees, except in some restricted areas where levels of pollution are very high. However, this does not preclude the possibility that air pollution is having an adverse effect on forest ecosystems as a whole, or on aspects of tree vigour that are not currently being monitored
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