Air pollution, Environment & Future. 35 years of research on forest, soils and water. Upplaga 1

The earth is 4.5 billion years old. The bedrock around Lake Gårdsjön, the gneisses and the granites, are 1.7 billion years old. The last glaciation is not more than 12,000 years away. Thus, soils in the forests around Lake Gårdsjön are relativley young from a geological perspective. The soils asr also very thin and has a poor buffering capacity. That is why air pollution in the last decades have had such a large impact on water and soil ecosystems around in Sweden and other countries on the Northen Hemisphere. During a very shortperiod in the history of the earth, less than 100 years, the ecosystems, groundwaters and lakes have changed under the impact of acidification. But, since the 1980s, air pollutions, especially sulphur dioxide, has decreased dramatically. This has resulted in a slow recovery of the ecosystems over much of the acidified land area in northen Europe. There are, however, still important environmental concerns. The nitrogen deposition it too high, as well as the concentrations of ground-level ozone.