Forest floor and soils in limed stands of substitute species in Klášterec nad Ohří forest district in the Krušné hory Mts

Forest ecosystems of the Krušné hory Mts. affected by long-term air pollution were finally disintegrated. The tree species composition has been changed in ecosystems disturbed in this way. Liming applied for the long-term revitalization of air-polluted areas partly decreased the effects of acid depositions on soil in spite of the reduction of air pollution; however, it did not cause any expected necessary changes yet. The aim of the paper is to evaluate the chemical composition of humus horizon H and organomineral horizon Ah (soil reaction, sorption complex, C/N ratio, available nutrients) in stands of substitute tree species differently affected by liming and site preparation in the area of Klášterec nad Ohří Forest District in the Krušné hory Mts. (Czech Republic). Based on our evaluations, we found out that pH values increased by 0.3-0.5, which was evident in stands with repeated liming at sites without soil preparation and with the site/soil preparation using an excavator or bulldozer. The majority of soils always showed an unsaturated base-exchange complex (< 50%). Increasing values of the sorption complex saturation were evident in stands with repeated liming, which is related to the favourable condition of pH in H and Ah horizons. C/N ratios in the H (Ah) horizon were always below a critical limit (< 24). The content of available nutrients in the H (Ah) horizon was insufficient. Among the particular elements phosphorus content decreased, that of magnesium reached optimum or even surplus, calcium was in surplus (optimum or even surplus), potassium in optimum (surplus). Forest management in the Krušné hory Mts. will be dependent on the effectiveness of the biological and chemical revitalization of soils also in the future.