Contemporary habitat and floristic changes in the sudeten Mts

Abstract

The authors present the, view that in the Sudeten forfounyivears paralelly eutrophication and acidification processes are taking place, as a result of industrial emissions. This view is based on results of bioindication studies on pollution arid accumulation of sulphur, nitrogen and heavy metals. At the same time, after 30 years., vegetation and floristic changes were investigited on permanent plots on the Snieznik and in the Karkonosze Mts. In most habitats a decrease of pH oveh 1.0 has been recorded. even in areas with calcium bedrock. Acid rains containing a lot of nitrates contribute to the fertilization of most of the ecosystems. The yearly fall of total nitrogen in the Suderen ranges from 38 kg in the Karkonbsze. to 59 kg/ha on the Snieznik. of nitrates - from 380 to 900 ppm/year. and sulphur, on the average. 1300 ppm/year in the whole Sudeten. The acidification of soil causes the maccessibility of alcaline elements (magnesium. calcium) and mobilization of harmful for plants aluminum. Overfertilization of habitats the lack of calcium and magnesium and the excess of aluminiurii cause unfavourable alterations in all phytocerioses in the Sudeten. The high mountain forests are particularly suffering but also the high mountain vegeration and abobve all the subalpine swards exposed to acid rains. Examples of plant species which adapt themselves to the new ecological conditions, and mountain plants which reduce their range are given. In general, the typical mountain flora and vegetation of the Sudeten is endangered in the existing ecological conditions.