ALGAL COMMUNITIES FEATURES OF LOWER REACHES OF ARCTIC RIVERS OF NORTH-EASTERN SIBERIA
Large rivers of the Arctic basin of northeastern Siberia, in contrast to the rivers of Western and Central Siberia, are less inhabited by humans and still retain a natural water regime. Nevertheless, the water ecosystems of the rivers in the region are subject to anthropogenic pressure, which is associated with the activities of extractive industries. Recently, industrial development of the north-eastern Siberia is accelerating not only in the catchment areas of rivers, but also on the shelf of the Arctic Ocean. Therefore, the relevance of studying the biodiversity of algal communities of the lower reaches of Arctic rivers and their estuaries is growing, as they are ecotones and are of great importance in maintaining biodiversity. There are a number of publications on the algal flora of the large Arctic rivers of the region. The purpose of this study is to reveal the key characteristics of the taxonomic composition of algal communities of Large Rivers of the Arctic basin of northeastern Siberia on the basis of original data and published materials to identify. The aim of this study is to identify the main features of the taxonomic composition of algal communities based on original data and published materials. As a result, the species richness of the lower reaches of the six largest rivers of the region was determined: Lena (637 species), Kolyma (187), Indigirka (185), Yana (111), Olenek (80) and Anabar (51 species). Differences in the reachness of floras are due to the different level of knowledge. We have demonstrated that the basis of the flora is made up of representatives of green and diatom algae. The revealed features of algal communities indicate that the water ecosystems of the lower reaches of the Arctic rivers of the region at this stage are mainly influenced by natural factors.