The influence of stocking on proton load in two submountain beech ecosystems

Air quality was investigated in two regions, model for the Central-European beech sub-mountain forests: one situated near an aluminium plant in the tiavnické vrchy Mts, heavy polluted in the past, and the other situated in the relatively slightly polluted Kremnické vrchy Mts, both in the West Carpathians Mts. In the years 1994--2006, we compared H+ concentrations between two beech stands at rotation maturity, a small-area clear cut and an open, non-forested plot. The highest proton load (H+) values (21.0mmol H+ day -1 m-2) were recorded on the small-area clear cut in the Kremnické vrchy Mts, the highest in the mature forest stands: 7.9 mmol H+ day -1 m-2 in the tiavnické vrchy Mts, and 7.1mmol H+ day -1 m-2in the Kremnické vrchy Mts. It follows that forest stands can act as filters capturing polluting substances. The results of the study show that the small-area forest regeneration at specific growth phase (small pole stage) starts to perform as a filter for gases and precipitation, that means, starts to perform the role of a forest stand. Apart from temporal and spatial trends, there was also evaluated the dynamics of proton load. The linear decreasing trend in the tiavnické vrchy Mts was affected by airborne pollutants, points out a reduction in polluting substances over the last two decades. On the other hand, the tendency in the Kremnické vrchy Mts has been moderately increasing since the turn of the centuries.