Most existing agricultural lands have been in production for sufficiently long periods that C inputs and outputs are nearly balanced and they are neither a major source nor sink of atmospheric C. As population increases, food requirements and the need for more crop land increase accordingly. An annual conversion of previously uncultivated lands up to 1.5 x 10⁷ hectares may be expected. It is this new agricultural land which suffers the greatest losses of C during and subsequent to its conversion. The primary focus for analysis of future C fluxes in agroecosystems needs to be on current changes in land use and management as well as on direct effects of CO2 and climate change. A valid assessment of C pools and fluxes in agroecosystems requires a global soils data base and comprehensive information on land use and management practices. A comprehensive effort to assemble and analyze this information is urgently needed.

Since the beginning of the 80's, a wide-spread damage to Norway spruce has occurred, mainly characterized by the light-induced decay of chlorophyll in magnesium-deficient needles. Damage also occurs in deciduous trees, especially in beech. To clarify the causes of the damage in Northrine-Wesphalian forests, extensive investigations have been carried out, which combined experimental techniques and epidemiologically orientated surveys.

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.

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.

Depending on their concentrations, air pollutants are dangerous to forests. With the exception of some industrial areas in the east, concentrations of air pollutants in Central Europe are below the damaging threshold as shown by the records of the monitoring stations.