Changes in air quality in different phases of forest management process in a sub-mountain beech ecosystem (West Carpathian Mts.)

We studied air quality in a sub-mountain beech ecosystem in the Kremnické vrchy Mts., Central Slovakia. We chose the method of passive sampling. The amounts of airborne pollutants (H+ and O3) were determined at regular time intervals, covering the whole vegetation period, on four plots with different stocking. The original stand was subjected to two cuts with a purpose to simulate the phases of a common silvicultural process. The first research period (1999-2003) started 10 years after the first cutting, the second (2004-2006) was launched immediately after the second cut. Ten years after applying the first cut, the differences in the proton load input were getting smaller - with the dynamically changing crown canopy. The largest difference in proton load (H+ was found between plots C and I after the second intervention, when the correlation coefficient value was 0.15. The differences in proton load input between the plots were influenced by the cut, especially in the first three years after its application. No significant differences in ground level ozone concentrations between plots I (intensive cut), Me (medium intensive), Mo (moderate) and C (control) were revealed either after the first or after the second cutting intervention. Differences in ozone concentrations are not significant, and they indicate that the stocking density does not play an important role in association with ozone affecting the stands. The increase in ozone concentrations after the second intervention was evident on all plots - indicating the absence of connection with the individual phases of forest management process, but at the same time indicating the presence of climate change. In the studied sub-mountain beech ecosystem in the Kremnické vrchy Mts., an important role of episodes with high ozone concentrations is evident.