ИСТИНА

Comparative evaluation of the alien species amount in flora of two reserves of the old cultivated territories of European Russia was done using «Alien plant Species» Data Base, created in the Institute of Geography, RAS (Moscow). The National park “Valdaiskiy” (Novgorodskaya oblast) (NPV) is founded in 1990. It is situated in the northern part of the Valdaiskiy upland on the border of the mixed coniferous-deciduous and southern taiga forest zones. On its area of 150 000 ha coniferous fur and pine forest plant communities dominate. The State Nature Reserve “Privolgskaya lesostep” (Penzenskaya oblast) (PV) is founded in 1989. It occupies the territory of 8370 ha in the south-western part of the Privolgskaya upland in the forest-steppe zone. The main plant communities are mixed pine and oak forests and meadow steppes. NPV vascular plants flora includes 746 species of 107 families (Morozova et al., 2010). In PL the whole amount of vascular plants species is 852 species of 98 families (Vasyukov, 2004). The spectrum of ten main families in two reserves is similar: Asteraceae, Poaceae, Rosaceae, Caryophyllaceae, Fabaceae, Ranunculaceae, Lamiaceae, Scrophulariaceae, Apiaceae. But the number of Cyperaceae species considerably diminishes in PL. The share of alien species is 18% (133 species of 42 families) in NPV and 11% (97 species of 29 families) in PL. Rosaceae (20 species), Poaceae (13), Asteraceae (10), Brassicaceae (10), Pinaceae (9) lead alien species spectrum in NPV. Asteraceae (18), Brassicaceae (14), Poaceae (11), Chenopodiaceae (7), Caryophyllaceae (6) are in the top of alien flora spectrum in PL. Most of families consist of 1-2 alien species. Cyperaceae is absent in alien flora spectrum of both reserves. Therophytes from various regions of Asia, Eurasia and Northern America prevail. Ergasiophytes dominate in NPV (53 species, 78% of alien species). This group includes decorative, food and forage plants, which run to wild. Xenophytes prevail in PL (68% of alien species). Species of this group is introduced to the new habitats by roads and railways. Efemerotophytous (species incapable to naturalize) prevail in NPV whereas in PL the number of epekophytous (species naturalized in secondary habitats) increases. Species with high invasive ability can become permanent component of nature and semi-nature communities. Among them there are species common for both reserves (Acer negundo, Lepidotheca suaveolens, Solidago сanadensis, Impatiens parviflora, Populus alba, et al.). Some species are met only in NPV (Aster salignus, Lupinus polyphyllus, Elodea сanadensis, Impatiens glandulifera), and some species are typical for PL (Amaranthus albus, Amaranthus retroflexus, Ambrosia artemisiifolia, Bidens frondosa, Conyza canadensis, Cyclachaena xanthiifolia). Thus, we can consider that in the forest zone alien species maintain its status longer due to conservativeness of local nature ecosystems. While in the forest-steppe zone naturalization of adventive species takes place comparably quickly. As a result alien species obtain status of local flora species.