Fungal biotrophic wood-destroying biota in forest ecosystems of European Russia

The objective of the paper is to substantiate the importance and role of fungal wood-destroying biota in the co-evolutionary dynamics of forest development, as well as to highlight the regularities of its behaviour in forest communities. Materials and Methods. The study subjects were primary spruce forests covering the entire habitat in taiga region of the East European Plain. Results. The author identified the main criteria of structural configuration of phytocenosis and mycocenosis in stable forests formed in the course of evolution. The following parameters were defined for phytocenosis: woodland concordance to the primary ecotope; the optimal structure of species composition according to silvicultural parameters; the complexity of age-related (variety of age within the same age-related generations) and horizontal (tessellation of trees belonging to different age-related generations) structure; optimal quantity and composition of natural primary forest regeneration; optimal amount of overaged wood of different mineralization steps. For wood-destroying biotrophic fungi the parameters were as following: a certain composition of fungi (quantitative and species diversity of fungi belonging to different nutritional modes), which depended on dynamic phases of biogeocenosis development and ecological conditions of their growth; the consistency in gradual growth of stressed trees in age-related groups and in the dynamics of the successive process; well-developed xylotrophic fungi complex, which contributes to the mineralization of overaged wood according to biomass accumulation by phytocenosis; change in biotrophic fungi behavior, e.g. their pest focal outbreak under phytocenosis structural change. If any changes take place in forest formation laws, which have been formed for centuries, wood-destroying fungi are evolutionary programmed to alter phytocenosis structures in order to reach the balance between the accumulating and mineralizing biomass, and therefore, to contribute to forest sustainability.