Silvicultural Assessment of Measures to Preserve Key Biotopes in Clear-Cut Areas in the Vologda Region

Clear-cutting leads to changes in the structure of biogeocenoses, the age and species composition of stands, and the diversity and abundance of vegetation. The article examines the results of a silvicultural and economic assessment of measures to preserve key biotopes with excessive soil moisture during clear-cutting carried out using cut-tolength and tree-length timber harvesting technologies in the Vologda Region. The results of the assessment of stand stability and floristic diversity in key biotopes have been analyzed, and the necessity and parameters for establishing protective zones have been substantiated. Monitoring observations show that the key biotopes identified during logging have been preserved within the boundaries. In key biotopes, rare and extrazonal plant species have not lost their viability. When assessing the diversity of flora, it should be noted that the number of species in biotopes with temporary excess moisture is, on average, 1.5 times higher than the number of species in adjacent stands before logging and 1.8 times higher than the number of species in stands in adjacent cuttings (1–7 years after cutting). In biotopes with constant excessive moisture, this indicator is 1.7 and 1.8 times higher, respectively. When clear-cutting is carried out using cut-to-length and tree-length timber harvesting technologies with and without preservation of key biotopes, the profitability of logging operations does not differ significantly. The feasibility of tree-length timber harvesting is 19.9 % higher than that of the cut-to-length technology, which is due to the lower cost of work. From a silvicultural and environmental perspective, the abandonment of key biotopes in the development of logging areas is an effective measure aimed at maintaining biological diversity at the local level. From an economic point of view, the preservation of key biotopes during clear-cutting is desirable and makes it possible to reduce production costs for logging operations by leaving non-operational areas with low-quality timber.