Changes in organic matter and upper mineral soil on clear cuts

Large-scale (i.e., > 1ha) clearcuts were studied in 2022–2024 at fifteen sites across the Czech Republic. Chemical properties and stock of selected elements were assessed in organic topsoil (OF+OH) and mineral soil (0–30 cm) layers in a block design on salvage-logged plots with different management of logging residues (cleaning vs. chipping) and adjacent control (survived) stands of Norway spruce (Picea abies L. Karst.). The rate of organic matter (OM) decomposition at the logged and control plots was evaluated based on the decomposition the experiments with standardized teabags and litterbags using the in-situ organic material (organic topsoil layer).

Changes in the water-extractable organic carbon (DOC) contents showed accelerated mineralization of organic matter on clearcuts. Significant differences in the quality of organic matter between the clearcut and a control stand were found only in the organic topsoil. No significant differences were found in the soil contents of risk elements (aqua-regia extracted As, Cd, Cu, Pb and Zn) between the clearcuts and a control treatment. Moreover, the distributions of risk elements in the soil profiles did not differ depending on the management of logging residues. Evaluation of the OM decomposition indicates slightly different weight loss of the samples from the stands and from the clearcuts, depending on the management of logging residues and the chemical composition of the organic layer.

This research was funded by the Ministry of Agriculture of the Czech Republic, project No. QK22020217.