Forest with broad-leaved species at the norther limit of distribution (Northwest of Russia)

Abstract

Monodominant broad-leaved forests are more typical on the northern limit of their distribution as was shown in the Leningrad region. This feature distinguishes these northern communities from forests located in their optimum range of the Central part of Russia where forests have a polydominant composite on of their stands. At the norther limit, the vegetation growing on sod-carbonate loam soil is closer to the real zonal broad-leaved forests. The northern forests with broad-leaved species are sensitive to soil factors and temperature valueas was revealed by the nMDS ordination of 53 geobotanical plots. Despite the dominance of nemoral species in the forests in both the north and south of the Leningrad region, the diversity, constancy and abundance of species associated with boreal evergreen forests are higher in the northern part of the region. This is a consequence of the presence of a significant share of coniferous and small-leaved tree species in the stands and less nutritious and acidic soils also. A high proportion of edge-meadow grass species and adventive weeds are associated with recreation and park care activities.