ABSTRACT
Deterioration in humid regions of the world, which includes the US Corn Belt and Europe's rich agricultural regions, also takes a heavy toll, though no one has calculated it. Lacking anything like the US Conservation Reserve Program, many countries have simply continued to farm highly erodible land until it turns into wasteland. Overall, the study estimates that the annual crop harvest in the United States has been lowered by at least 5 percent because of air pollution and perhaps as much as 10 percent. In vegetation, ground-level ozone—the most broadly destructive form of air pollution—causes damage to the photosynthetic mechanism and to leaves, and it provokes changes in growth rates, yields, and quality. Research from the major Antarctic biological stations has shown that at current levels, ultraviolet radiation from the sun harms phytoplankton cellular processes, including reproduction, DNA integrity, and survival.
