Diatom diversity and ecological variables in the Arctic lakes of the Kostyanoi Nos Cape (Nenetsky Natural Reserve, Russian North)

Species richness varies from 9 to 97 per lake with Aulacoseira islandica (O.F. Müller) Simonsen, Fragilaria mesolepta Rabenhorst, Psammothidium subatomoides (Hustedt) L. Bukhtiyarova and Round as dominant species. Bioindication attests to preponderance of temperate, moderately oxygenated, low-to-moderate organic-enriched alkaline, and circumneutral low saline water.

Oligotrophic to mesotrophic state correlates with the type of sediments and low organic pollution (saprobity index 0.81–1.73 and Classes 2–3 of water quality). The diatom assemblages contain cosmopolitan species accompanied by the large group of 45 boreal species including 28 Arctic–alpine taxa. Canonical correspondence analysis shows conductivity and the type of sediments being the most important variables.