Alien Plant Species in the Russian Arctic: Spatial Patterns, Corridors, and Local Invasions

The diversity of alien plant species in the Russian part of the Arctic (RA) is analyzed by generalizing different publications. Alien plant species are found in all regions of the RA, but their share in regional floras is relatively small compared with more southern biomes and is unevenly distributed, from 1-2% in the north of Yakutia and in the continental part of Chukotka to 22-27% on the Kola Peninsula and in the Bolsheze-melskaya tundra. The low species diversity of alien species in the RA is explained by two groups of factors. The first one includes social and economic indicators: relatively late and still focal economic development of the region and generally low human migration activity here. The second one combines natural factors, among which the climate is of paramount importance. It has been shown that plurizonal species with the northern border of their ranges in the boreal zone are mainly introduced into the RA, but the direct donor regions are often not known when alien species are introduced. These species are clearly better adapted to a wide range of conditions, allowing them to survive in the harsh Arctic climate. By the way of invasion into the RA, unin-tentionally introduced species prevail, and transport, migration activity, Arctic tourism, and introduction with contaminated materials are the main pathways. The distribution of alien species is local, and it is mostly associated with settlements and industrial centers.