How Will Increased Ultraviolet Radiation Affect Forests?
Forests occupy about 31 percent of the Earth’s land area. Forests make up over 90 percent of the Earth’s biomass. Forests account for two-thirds of the carbon that is “fixed” or withdrawn from the atmosphere. Forests thus play a major role in how much carbon is free in the atmosphere, which in turn affects the magnitude of the “greenhouse effect.” Forests regulate not only the flow of water, but local, regional and global climate. Now add another fact: We know next to nothing about what effect increased ultraviolet-B radiation will have on forests as the stratospheric ozone shield continues to disintegrate over the next century. Also, since global processes do not operate in isolation, how will the UV-B effect on forests affect their ability to cope with anticipated global warming? Most research on the effect of increased UV-B on plants has been done on annual plants, such as crop plants, says tree physiologist John Bassman. But trees are much different in their relationship to increas
