Taxonomic structure and ecological-geographical characteristics of florocoenotic complex of the Russian Arctic coast

In the coastal zone of the Russian Arctic seas the saline habitats are formed on the muddy coastal flats, in the estuaries and bay areas of the rivers with specific communities of plants. These communities of plats are characterized by unique structural and functional integrity. From 1974 to 2014, on the coasts of seven Russian Arctic seas a study of the florocoenotic complex was conducted. On the example of some model objects (the coasts of the White, Barents, East Siberian, Chukchi and Bering seas) more than 30 partial coastal floras were investigated. Herbarium materials and literature data on the composition and structure of the Kara vegetation and the Laptev seas were used. The analysis of partial coastal floras was performed by the use of standard floristic methods. The flora of studied coastal ecotypes includes 113 species of vascular plants (12 % of the total flora of the Russian Arctic), belonging to 63 genera and 31 families, which confirms the outmost significance of the role played by the coastal ecosystems in taxonomic diversity of the Arctic region. In the top ten leading families in the taxonomic spectrum of the florocoenotic complex of the coasts of the Russian Arctic seas, in comparison with the taxonomic spectrum of leading families of the local Arctic floras, the first three places are occupied by the family of Poaceae, Cyperaceae and Asteraceae. Higher position are taken by the families of Chenopodiaceae, Plantaginaceae, Apiaceae. The circumpolar arctic species that represent the euarctic autochthonous elements of the coastal flora dominate in the geographical structure of the florocoenotic coastal arctic complex. The dominant role in the plant composition of low salt marshes of the arctic and circumpolar euhalophytes is taken by the hypoarctic amphioceanic mezohalophytes.