Epiphyton of oligotrophic lakes of Leningrad region

Abstract

Here are results of investigation of taxonomic composition, community structure and dominant species of epiphytic algae in 12 oligotrophic lakes located in different geomorphic regions of Leningrad region. In summer epiphytic communities there were 385 algal taxa, they belonged to 6 taxonomic divisions: Cyanophyta (Cyanoprokaryota) – 50 (13%), Bacillaryophyta – 175 (45%), Chlorophyta – 37 (10%), Charophyta – 118 (30%), Xanthophyta – 4 (1,55%), Rhodophyta – 1 (0,45%). The taxonomic structure of each lake was predominant diatoms and desmids, but the biomass was dominated by zygnems and green algae. In total, the taxonomic composition of the epiphyton in the studied lakes is similar, the differences are revealed at the species level. The structure of dominanting epiphyton complex was rather constant and composed by a small number of species. The greatest contribution to the epiphyton was made by Tabellaria flocculosa and species of the genus Bulbochaete. The structure of the epiphyton reflects the undisturbed nature of lake ecosystems, as well as their northern location.