Morozova. East Asian species in the alien flora of European Russia. In: The East Asian Flora: and its role in the formation of the world’s vegetation

East Asian species in the alien flora of European Russia

Olga MOROZOVA
Institute of Geography RAS, Moscow, Russia

Due to its geographical location, European Russia may be presented as a crossroad between West and East. There are about 1750 alien species reported from this territory that is considered one of the important portals for alien species of eastern origin to Europe. This study aims to examine European Russia's alien plant species originating from East Asia. These species make 14.5 % of species alien to whole territory of European Russia and about 5.5 % of the total number of alien species. These alien plant species, all of which are neophytic, were analyzed with regard to their floristic status, biological and ecological attributes. The proportion of East Asian alien plants in district floras ranges from 0.4 to 7.5 %. There are nospecies recorded from all districts; one quarter is found in more than 10 districts. Intentional introductions (70 % of the total number of aliens) prevail over unintentional (30 %); ornamental and horticultural introductions escaped from cultivation predominate. The invasive status of species changes according to geographical location of districts, and it is impossible to name their exact number. There are about 55 % casual, 30 % naturalized and 9.5 % invasive species (in the sense of Richardson et al. 2000) recorded from 48 of 52 administrative districts. Naturalized species are present in a half of the districts studied, and only four species of a total number of accidentals may be considered as naturalized. The pattern of distribution arises partly for scientific reasons (e.g. lack of alien species research, inaccuracy of data), but there are also climatic influences. Five of East Asian species are serious invaders in European Russia: Rosa rugosa - in the shore of Baltic Sea, Reynoutria japonica - in the North of Central Russia, Sorbaria sorbifolia - in Central Russia, Ulmus pumila and Zizania latifolia - in the southern districts of European Russia, two of these are invasive in many European countries.