In the thesis we wanted to analyze the effects of two thinning types, namely classical selective thinning and situational thinning with final crop trees, which are most often carried out in pure beech stands. We compared differences in the effects of thinning type on individual trees and stands. Therefore, we performed the second consecutive full survey on 9 research plots on the Brezova reber study site, and then performed also the harvesting in accordance with the thinning type on each plot. Before the 2019 growing season, we measured the dbh of all trees on plots, assessed some other tree parameters and measured height of selected trees. We calculated the basic indicators of stand structure and composition, including the SDI index, monitored their changes between the two measurements and compared them between three different treatments (also the control plot without intervention). The average diameter and volume increment of trees was the highest under the classical selective thinning, while the increments of crop trees were largest under the situational thinning. The stand volume increment was significantly higher on plots with applied classical selective thinning than on those with situational thinning; the lowest was on the control plots. This can be attributed to the effect of growth acceleration in young and middle-aged stands. The thinning intensity decreased significantly compared to the previous thinning. The thinning intensity in terms to stand volume was higher under the classical selective thinning, while the thinning intensity in terms of competitors per a crop tree was higher under the situational thinning.
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