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.

Forest decline became a matter of public and scientific concern in France in 1983 when conifers in the Vosges mountains were found to exhibit unusual crown deterioration. An impassioned controversy on a supposedly large scale forest health problem was then in full swing in Central Europe. A co-ordinated research programme entitled DEFORPA ("Deperissement des For~ts et Pollution AtmospMrique") was launched in 1984. This programme ran from 1984 to 1991 and a number of projects are still in progress. The Programme was sponsored by three French ministries (Enviroument, Agriculture and Forestry, Research and Technologyl), several state agencies, various regional authorities and the Commission of the European Communities (DO xn and DG VI). Initially, emphasis was solely laid on the understanding of forest decline in the mountainous areas - because damage was most obvious there - in relation to natural and man-made factors. Air pollution was given high but not overwhelming priority. Thus, the DEFORPA Programme was not in its essence a nation-wide assessment of air pollution effects, unlike a number of national acidification research programmes in Europe and North America. During. the programme, however, the areas of concern expanded. In particular, research into water acidification in the Vosges mountains was developed in parallel with the DEFORPA Programme, and possible eutrophication of the ground flora in northeastern France became the subject of new research.

In the early 1980s there were several published reports of recent, unexplained increases in mortality of red spruce in the Adirondack Mountains and the northern Appalachian Mountains of the eastern United States. These reports coincided with documentation of reductions in radial growth of several species of pine in the southeastern United States, and with the severe, rapid, and widespread decline of Norway spruce, silver fir, and some hardwoods in central Europe. In all of these instances, atmospheric deposition was hypothesized as the cause of the decline. (Throughout this volume, we use the term "decline" to refer to a loosely synchronized regional-scale deterioration of tree health which is brought about by a combination of stress factors. These may be biotic or abiotic in nature, and the combinations may differ from site to site. ) Heated public debate about the causes and possible cures for these forest declines ensued. Through the course of this debate, it became clear that information about forest health and air pollution effects on forests was inadequate to meet policymakers' needs. Ecology and Decline of Red Spruce in the Eastern United States addresses that gap for eastern spruce fir forests and represents the culmination of a great deal of research conducted in recent years. The focus is on red spruce because the decline of red spruce was both dramatic and inexplicable and because of the great amount of information gathered on red spruce.

This is the only book to offer an up-to-date overview of air pollution in East Asia and the effects of air pollutants such as ozone, acid deposition and aerosols on Asian crops and trees. It is unique in that it discusses the fundamentals of environmental plant science and research advances in the area at the plant ecophysiology level. It addresses various topics, including gaseous air pollutants such as ozone; soil acidification and atmospheric nitrogen deposition due to acid deposition; PM2.5 and the effects of air pollutants on growth, yield and physiological functions such as photosynthesis of crops and trees in East Asia. It is a valuable resource for environmental scientists, plant scientists, government officials, industrialists, environmentalists, undergraduate and graduate students and anyone interested in the application of the latest findings to agricultural production and protection of forest ecosystems in Asia. It also provides useful information for professionals involved in research, development, production, processing and marketing of agricultural products, including those in developing countries who are interested in advanced environmental science in this field.

Acidification of the environment--caused by the emission of sulfur and nitrogen oxides into the atmosphere--is one of the most serious side effects of industrialization. This volume provides a thorough introduction to this global problem. A basic overview describes acidification processes occurring in the air, water, and soil, and relates other facts known about the acidification of the tropical environment. There is also discussion of potential future impacts of emissions which cause acidification. Includes a series of case studies focusing on acidification problems in specific countries in the tropics.