ZLV Online

Abstrakt

Moldava plots are situated in the Ore Mts., the area of historically high air pollution. Since the second half of the 1970s deposition is measured in open area (bulk) and in the spruce stand (throughfall). After the stand was felled in 1980, deposition has been measured in the regenerating transitory stand of mountain ash. Also soil water chemistry and runoff water are monitored. In 1977, 1980, 1988, 1994 and 2003 the chemical properties of the soil and humus horizon were analysed. The results confirm general decrease of deposition in the 1990s, reflected also in gradual increase of the soil pH and pH of soil solution. However, in the transitory stand of mountain ash the amount of available basic cations is still decreasing. In the clear cut the content of available K and Mg increased, Ca content decreased. The difference between deposition and the loss in runoff water shows a negative balance of Ca, Mg, but N and SO4 2- as well. Cation content in humus and soil depends, under current litterfall level, on their pool in primary minerals and the speed of their release. Under existing condition mainly soil calcium content seems to be critical for the stand growth in the future.