The impact of clear-cutting on the plant biodiversity of middle-taiga spruce forests

The effect of principal felling in mature middle taiga Siberian spruce forests (Piceetum myrtillosum, Piceetum polytrichoso-sphagnosum) on the number of undergrowth and the species composition of the herb-dwarf shrub and moss-lichen layers was studied. It was found that on 4-year-old spruce clear-cuts the average density of undergrowth varies from 7.0 to 8.8 thousand ind.·ha-1. The ground cover composition completely or almost completely lacks the most typical species of mature spruce forests such as Oxalis acetosella, Gymnocarpium dryopteris, Deschampsia flexuosa, Galium boreale, Lycopodium clavatum, and L. annotinum. An extensive spread of the light-demanding pioneer species Chamaenerion angustifolium is observed. A comparative assessment of the projective cover and species diversity showed that successional processes occur in the living ground cover.