Aгарикоидные базидиомицеты зеленых насаждений города Петрозаводска (Республика Карелия)

Abstract

The paper reports the results of studies on the taxonomic and trophic structure of agaricoid basidiomycetes in urban stands of the main forest tree species of the boreal zone (Betula, Larix, Picea, Pinus). Altogether 111 species of macromycetes of 59 genera, 33 families and 8 orders were found. The leader in terms of the number of species in this mycobiota is the group of mycorrhiza-forming fungi. The biota of agaricoid fungi is of the boreal type with the taxo-nomic structure most vividly demonstrating the traits of the mycobiota typical of the middle taiga subzone of Karelia. A distinctive feature of the mycobiota is the high number of species in the families Agaricaceae and Russulaceae, which are common in ruderal habitats and the forest zone. A comparison of the species composition and ratios in the taxonomic structure of the mycobiota between plant communities of urban and undisturbed areas, as well as Karelia in general showed a low level of similarity and pointed to gaps in the current inventory of agarics in the boreal zone of Republic. The highest species diversity of macromycetes was found in spruce stands, and the lowest in larch stands. The structure of the agaricoid fungal biota in sample plots in the spruce-, birch- and larch stands was relatively stable, with some fluctuation. As to the structure of the pine stand mycobiota, the spectrum of families ranked by the number of species in them changed along the human pressure gradient, and the trophic structure changed accordingly. The number of symbiotrophic species decreased, litter-related saprotrophs disappeared, the leading position was taken over by humus-related saprotrophs. The surveys revealed the presence of 11 red-listed species classified into two categories – near threatened (NT) and data deficient (DD) species.