The results of phytoperiphyton studies in 92 watercourses of the White Sea basin are summarized and analyzed. Totally 540 taxa with a rank below the genus were identified. They belong to six divisions: Cyanophyta – 76, Ochrophyta – 374, Euglenophyta – 3, Dinophyta – 4, Rhodophyta – 8 and Chlorophyta – 75. Diatoms, cyanobacteria and chlorophytes form the basis of the species diversity (> 90%) in all studied rivers. The predominance of these groups reflects the specificity of the phytoperiphyton in the river systems of the boreal and subarctic zones. Leading families are Naviculaceae (174 species), Achnanthaceae (45), Desmidiaceae (43) and Fragilaceaceae (36). Together they cover 337 species or 65% of the total number of species found. The group of leading genera (187 species, 35%) includes Eunotia – 36 species, Achnanthes – 33, Navicula – 48, Pinnularia – 39, and Cymbella – 31 species. The heterogeneity of the climatic regime in the study area determines the simultaneous presence in the algae flora of widespread eurythermic species characteristic of the taiga zone, stenothermic rheophiles of alpine origin and the boreal complex typical of wetlands. The dominant complex is represented by a small number of species resistant to dynamic water loading. It is noted that the ecological-geographical spectra of algae are dominated by widespread oligogalobic species, acidophilic or indifferent to the pH of the medium. The relative importance of indicator species in the formation of groupings allows to refer the waters of the studied watercourses and reservoirs to the second class of purity.
Phytoperiphyton of watercourses from the White Sea Basin (Murmansk District, Republic of Karelia, Russia)
