Home – Home – Jornals – Siberian Journal of Forest Science 2019 number 6

The distribution of woody plants in terms of diameter and height was studied in virgin indigenous monodominant pine communities with the last fire of 5-130 years. High lability of morphometric characters of trees and undergrowth are shown. The types of age and vertical structure of stands are revealed. Both stepwise-different-aged and conditionally different-aged stands are formed under the influence of the pyrogenic factor. Pine stands have «regular top», «regular bottom» and «symmetrical» vertical structure. The horizontal structure of stands and undergrowth was interpreted based on the analysis of point processes using the pair correlation function. Trees are distributed on area randomly. We observed weak aggregation of young trees in stands on distances of 2-6 m. Both undergrowth and self-sowing are characterized by group distribution at small distances of up to 1-2 m. The direction of the displacement of the projections of the tree crowns centers relative to the bases of their trunks is ambiguous. The shift of the crown space towards the maximum solar radiation was detected in thinned stand with high age and big size of trees. In other types of pine forests no one-sided orientation of tree crown development was revealed. The position of the tree crowns centers on the plot shows the same spatial distribution as the base of the trunks. In phytocenoses with the presence of a young generation of trees, the effect of «convergence» of crowns is manifested due to the inclination of their thin and elongated trunks under snow pressure. It leads to a denser structure of the distribution of projections of crown centers in comparison with the position of the bases of the trunks of young trees on the plots.