Altitudinal zonation of vascular plants of "Verhneindigirskiy" resource reserve (Russia, North-Eastern Yakutia)

«Verkhneindigirsky» resource reserve is located on the territory of the Russian Federation, in Oymyakon Highland, near the border of Yakutia, Magadan Oblast and the north of Khabarovsk Krai. Altitude interval marks from 850 to 1200 (1700) m above sea level. The research area is located in the extreme climate of the North pole, where winter air temperatures reaches – 65–70° С, and the solid thickness of permafrost is 400–700 m. Vegetation is characterized by altitudinal belts: forest, subgoltsy shrubs, epilithic-lichen communities and the complex of valley vegetation. Mountain-tundra vegetation is limited, it is not presented as a separate belt and usually is included in the structure of other vegetation belts. The vast majority of species (292, or 87%) are concentrated in the valley vegetation complex. On the mountain slopes the diversity of flora is greatly reduced: in the forest belt — 139 species (41%), in the subgoltsy shrubs belt — 47 species (14%), and in the lower part of the epilithiclichen belt — only 8 species (2%). In general, the distribution of flora of the resource reserve by altitudinal belts corresponds to that in the near-located system of Verkhoyansky Ridge. However, the proportion of plants in the valley complex is increased compared to the plants on mountain slopes, and there are no components of the tundra belt due to the more severe natural and climatic conditions of the investigated territory