Benthic invertebrate communities of lakes in the Polar Ural Mountains (Russia)

Abstract

As in many Arctic regions, the fauna and biodiversity of Polar Ural lakes are not widely known. However, the fauna of these northern, relatively pristine lakes has recently become threatened due to industrial development in the Arctic. In this study, the zoobenthos of 13 relatively large lakes and 9 small ponds was studied during the summer (July and August) from 2003 to 2013. The aim was to conduct a taxonomic inventory of benthic communities in the Polar Ural lakes by combining available literature data with new information about the species composition of the zoobenthos. The lowest diversity and abundance values were found in cold deep lakes with large boulders and little algal growth, whilst the highest values were found in lakes with well-developed aquatic and riparian vegetation. In the littoral zone, Crustacea (Harpacticoida, Cyclopoida, and Cladocera) were the most abundant group, followed by Chironomidae, Nematoda, and Oligochaeta. Insects such as Plecoptera, Trichoptera, and Coleoptera accounted for only 4% of the total abundance. In the profundal zone, Chironomidae larvae and Crustacea were numerically dominant, and the share of Ostracoda was much higher than that in the littoral zone. Overall, a total of 208 invertebrate taxa (including 160 species) were recorded. The most diverse groups were Oligochaeta (43 taxa), Crustacea (36), Trichoptera (25), Mollusca (28), and Chironomidae (22). In the future, the faunas of these Arctic lakes can be used as indicators of regional and global climatic changes and in investigations of the adaptation of aquatic invertebrates to extreme environments.