Atmospheric pollutant can cause direct effects mediated by foliage and indirect effects mediated through soil. Biotic and abiotic factors can confound relationships among nutrient cycling, growth loss and mortality and air pollution. Changes in the soils could result from acidic deposition. Changes could include increased fertility as a result of sulphur and nitrogen input to soils that are deficient in these elements or decreased fertility through ion leaching or mobilization of toxic substances as aluminium.

Wood will have a great importance as renewable raw material. Forest devastation endangers the world's future wood supply. We need a long-term strategy for forestry and forest products industries to protect complete ecological life cycle.

Climate change will be the major impact on all forests, included increased risk of large-scale fires, enhanced susceptibility to insects and diseases. Direct effects of air pollution on vegetation include damage to protective surface structures, disturbance of photosynthesis.

Considerable uncertainty has surrounded the relationship between forest growth and forest declines in Europe. Although growth decreases have been recorded in several years, by the end of the 1980s, increment at many sites had reached a level higher than any previously recorded. Fertilization by carbon dioxide, favourable climatic conditions and better stand management may all have contributed.

The report summarizes scientific information about forest ecosystems and their relationship to climate change and air pollution, with special emphasis on forests in Europe, North America and China. The contributions reflect the current state of science, but also uncertainties and gaps in scientific knowledge.

Climate change effects on forest soils will occur directly on soils or indirectly through effects on tree growth. Increases in soil temperature will cause an increase in soil respiration and decomposition and many increase rates of mineral weathering and ion exchange reactions. Forest soils represent a major sink for C and increased productivity in response to elevated atmospheric carbon dioxide will lead to an increase in c storage in forest ecosystems. Changes in forest productivity will have significant effects on forest soils, included water use, soil moisture status and nutrient cycling.

Two modeling approaches were applied to evaluate the potential risks of increasing atmospheric carbon dioxide concentrations and possible climate change on the vegetation cover of the Alpine region. The first model is a stochastic forest succession simulator, the second is a static regression type model. The questions of the study were as follows: (1) Which temporal vegetation changes might occur under given carbon dioxide and climate scenarios? (2) Which region of the Alps might be most susceptible to a vegetation change?

Tropospheric ozone is the most important single air pollutant of importance to forests in eastern United States. Both broadleaf and needled trees may suffer premature foliar senescence following even low ozone exposure years. Genetic sensitivity within species is likewise prevalent.

The area of productive woodland in the UK has been increasing steadily since 1950, generally at about 20-30 thousand hectares per year. The current forest estate covers 2,1 million hectares, the annual growth in the total stored carbon in wood is 2,0 million tonnes. The annual UK output of carbon dioxide from the burning of fossil fuels is 162 million tonnes.