Beskydy 2015, 8, 101-110
The effect of thinning on humus conditions in spruce and beech stands in the Highlands area of the Czech Republic
The study evaluates the effect of the type of thinning (above thinning vs. below thinning) on the humus conditions (i.e. forest floor stock, the content and stock of carbon and nitrogen, C/N ratio, and the proportion of carbon in humic substances) in spruce stands found on acid granodiorite (acid site) in forest vegetation zone (FVZ) 4 to 5 (Field research station Rájec-Němčice /FRS/, Department of Forest Ecology /DFE/ Mendel University in Brno) and in beech stands found on a solidified limestone sediment (nutrient rich site) in FVZ 3 to 4 (Training Forest Enterprise Masaryk Forest Křtiny /TFE Křtiny/); the sites indicated above are part of the upland of Drahanská vrchovina Upland (Czech Republic). Thinning was conducted in spruce stand in 2005, 2010; in beech stand in 2011. The stock of forest floor was determined to be 17–18 t.ha-1 under the beech stands and 51–54 t.ha-1 in the stands of spruce. The C/N ratio in the layers of forest floor and soil horizons at each site is similar and is not statistically significantly different. In spruce and beech stands in layers F and H fulvic acids prevail – a lower HA to FA ratio, the transformation of humic substances is more complete in layer H under spruce stands compared with beech. In the Ah horizon, the situation is reversed, with the transformation of humic substances being more complete under beech stands. The results incorporated using multivariate statistical methods (PCA) confirmed that thinning has no statistically significant effect on humus conditions in young spruce and beech stands in different types of habitats.
Keywords
type of thinning, spruce and beech stands, forest floor and soil, Drahanská vrchovina Upland, the Czech Republic.
Funding
The study was developed under the financial support of the research project entitled IGA LDF 33/2014 “The effect of the strong increment thinning – synthesis of the ecological-production study”, and the research project of Ministry of Education of the CR, project COST LD14018 “Sustainable management of mixed forests in highland areas“.
