East Asian Species in Alien Flora of European Russia
Plants of East Asian origin are the important group of species introduced to many regions of the world; three of them are among 100 most widespread invasive species in Europe. Due to geographical location and vast territory of the region of European Russia, which borders with Asia and spreads across a wide range of climatic and vegetation zones, it can be considered as a transitional area between Europe and Asia. One hundred and six East Asian species comprise the second biggest group in the species pool of aliens to whole territory of European Russia and make about 5.8 % of the total number of its alien plants. Invasive status of species was assessed for different regions; it may vary depending of geographical location of the species pool. Summarizing the data by regions alien flora of East Asian origin includes about 60 % of casual species, 30 % of naturalized and 10 % are considered to be the invasive species. The majority of East Asian species (79) were brought to European Russia deliberately; the history of their introduction was similar to that in other European countries. Forty two species of them have naturalized. Twenty three species of East Asian origin were accidentally introduced, and five of them have naturalized. Some East Asian species appeared in European Russia by chance may be transported across the territory of European Russia further to Europe. Of eleven East Asian invasive species in European Russia Rosa rugosa occupied preferably the coast of the Baltic Sea, Reynoutria japonica, R. sachalinensis, Sorbaria sorbifolia and Hordeum jubatum - the Central regions of Russia, Ulmus pumila, Zizania latifolia, Cotoneaster lucidum, Hemerocallis fulva, Morus alba and Monochoria korsakowii - the southern areas of European Russia.