Air pollution is a problem affecting every part of our planet however, its global effects are poorly understood. This book provides the first truly global assessment of the scale of impacts of air pollution on crops and forests. The core of the book comprises assessments of the problem by experts from 12 different countries on every continent — describing the evidence of air pollution effects on crop yields and forest vitality with regard to environmental policies. These analyses are placed in the context of a global assessment of the scale of current and future air pollution levels, as well as in the socio-economic context of local production systems./a

An analysis of trees in Washington, D.C. reveals that this city has about 1,928,000 trees with canopies that cover 28.6 percent of the area. The most common tree species are American beech, red maple, and boxelder. The urban forest currently store about 526,000 tons of carbon valued at $9.7 million. In addition, these trees remove about 16,200 tons of carbon per year ($299,000 per year) and about 540 tons of air pollution per year ($2.5 million per year). The structural, or compensatory, value is estimated at $3.6 billion. Information on the structure and functions of the urban forest can be used to improve and augment support for urban forest management programs and to integrate urban forests within plans to improve environmental quality in the Washington, D.C. area.

Proceedings of the Twenty-Second NATO/CCMS International Technical Meeting held in Clermont-Ferrand, France, June 2-6, 1997

There is not much question that plants are sensitive to air pollution, nor is there doubt that air pollution is affecting forests and agriculture worldwide. In this book, specific criteria and evaluated approaches to diagnose the effects of air pollution on trees and forests are examined.

The public's attitude toward air pollution in the United States evolved substantially during the 1960s. One of the results of the nation's emerging environmental ethic was the creation of the U. S. Environmental Protection Agency (EPA) in December of 1970. Prior to this time, research was focused on the impacts of air pollution on human health and welfare and was largely conducted by several federal research agencies, which included the Department of Health, Education, and Welfare; the National Oceanic and Atmospheric Administration; and the U. S. Department of Agricul ture. After the creation of the EPA, much of this work was consolidated in one regulatory agency, which resulted in periodic evaluations of the various effects of atmospheric pollution on human health, materials, agriculture, and forest ecosystems. At the same time that environmental interest was growing in the United States, concern increased in the European scientific community and public over the ecological impacts of acidic deposition. As the magnitude of the damage to European lakes and streams and the widespread decline in Norway spruce and silver fir was reported, concern that similar problems were occurring in the United States increased substantially. This concern was heightened by press reports of high elevation spruce-fir forest declines in the Adirondack and Appalachian Mountains and the decline and death of sugar maples in the northeastern United States and Canada.