Spatial structure and morpholody of understory in the southern taiga zone of central Siberia

Abstract

The spatial structure of understory is influenced by various biotic and abiotic factors. The aim of the present study was to reveal the role of spatial distribution of the understory and its influence on the morphological and other forest characteristics in young stands. Visual and instrumental forest measuress were conducted to assess the spatial distribution of understory (forest inventory data for Boguchanskoye, Daurskoye and Manskoye forestries in 1965–1975 were used). In Central Siberia, the spatial structure of understory is significantly influenced by the number of understory trees and the share of conifers in the stand composition. Quality of the understory worsens with increase in its number and age. At the same time, the condition of young trees growing in groups is lower. Competition in groups accelerates growth in height, making trees growing in groups higher than those arranged uniformly after 30 years of age. It was confirmed that the spatial structure of understory changes from a group to a uniform one with age. The analysis of variance showed that group arrangement of the understory significantly influences its quality and the share that dominant forest-forming species (spruce) takes in the young generation. In the case of uniform arrangement, a significant characteristic is the number of understory trees. Group spatial structure significantly influences the quality of understory and its growth rate in the southern taiga zone of South Siberia. In Central Siberia, abandoned agricultural lands are restocked mainly with coniferous (Scots pine) and deciduous (birch) species.