The species composition of tree and shrub plantations and their forest pathological state

Abstract

The stability of forest ecosystems and their resilience in the event of stressful situations is determined by the species composition of tree and shrub plantations. Forest ecosystems represent a biological system consisting of a community of interconnected living organisms dominated by woody vegetation, with the direct influence of abiotic factors complex. The research purpose is to determine the composition of tree and shrub species and their forest pathological state. 13 species of trees (3 species of coniferous species, 10 species of deciduous species) and 6 species of shrubs grow on the territory of the Volzhsky forestry. In the composition of the forest stand, the tree species proportion varies from 0.1% to 29.4%, the shrubs proportion varies from 0.1% to 8.3%. Among deciduous species, lanceolate ash dominates (29.4%), among conifers, Siberian larch (12.7%), and among shrubs, common lilac (8.3%). The conducted studies allowed to identify 28 species of harmful organisms (18 species - pests and 10 species - pathogens of fungal, viral and non-infectious diseases). Among the pests, the ecological group of pests of leaves and needles was the most represented - 37.9% in tree species and 11.1% in shrubs, among diseases - diseases of trunks and branches - 19.7%. The tree species most affected by diseases and damaged by pests was the small-leaved elm, so in 94% of the trees the leaves were damaged by pests and in 59% of the trees the trunks and branches were affected by diseases.