Semeniuk N. Epiphytic algal communities of the Dnieper basin waterbodies

The paper considers patterns of epiphytic algal communities’ taxonomic composition, cell count, biomass, primary production, their continuity and discreteness in waterbodies and watercourses of the Dnieper basin, the main mechanisms governing their response to natural, human and biotic variables. A total of 715 species (743 infraspecific taxa, including the nomenclature species type) were identified in the epiphytic algal communities of the Dnieper basin, with 15 species and infraspecific taxa being new for Ukrainian flora. The “alternative stable states theory” has been proven applicable to aquatic ecosystems of the Dnieper basin, with high productivity of epiphytic algal communities corresponding to “clear water regime” and low productivity – to “high turbidity regime”. Epiphytic algal communities possess efficient mechanisms sustaining their homeostasis, which can be implemented due to their high taxonomic richness and evenness. The European approaches (diatom indices) have been applied to the assessment of state of aquatic ecosystems within the Dnieper basin according to epiphytic algal communities.