Features of organization of populations of alpine endemic Anemonastrum biarmiense (Juz.) Holub in the South Urals State Natural Reserve

Anemonastrum biarmiense - Ural alpine endemic in a number of places going down to the mountain forest belt, is a rare plant of the Urals. The species is distributed in the upper belts of mountains from the South Urals to the southern part of the Polar Urals. In the South Urals the species is found in all high mountain ridges above the level of the forest boundary (mountains - Iremel, Yamantau, Shatak, ridges - Taganay, Zyuratkul, Nurgush, Urenga, Zigalga, Mashak et al.). In the mountain-forest belt it grows in mountain pine, larch and birch forests, on the steppe slopes, on the banks of mountain rivers (on the ridges Krakow, at the foot of mountains Iremel, in upper courses of the rivers Yuryuzan and Belaya). It is included in the Red Books of the Sverdlovsk region (III category), Komi Republic (II category), Khanty-Mansi Autonomous Area (III category), Yamal-Nenets Autonomous Area (III category), Tyumen region (III category). It was included in the Red Data Book of the Middle Urals (III category). The aim of the study was to reveal the features of ontogenetic structure of coenopopulations of A. biarmiense, growing in the remote mountain area of the South Ural Natural Reserve. In 2015 there were studied: Mashaksky midmountain area of the central part and Eraktashsky mid-mountain area of the southern part of the South Ural State Natural Reserve. 12 coenopopulations of the species are studied in the investigated area. Leading population characteristics were defined: total and effective density of individuals, age structure. Studying of age structure of populations was carried out by standard techniques. L.A.Zhivotovsky’s “delta-omega” criterion based on sharing of indices of age (Δ) and efficiency (ω) was applied to assessment of condition of coenopopulations. In the course of study of this species there was an attempt of differentiation of its place of growth for the mountain-forest and mountain-tundra belt. Coenopopulations 1-7 are located in the mountain-forest belt, coenopopulations 8-12, respectively, in the mountain-tundra belt. Total density in coenopopulations of A. biarmiense, located in the mountain-forest belt varies from 6,9 to 15,3 ind./m2,effective density - 2-6 ind./m2, in mountain-tundra belt the density values vary from 10,3 to 25,0 ind./m2, effective density - 3,6-6,2 ind./m2. In most populations the pregenerative fraction prevails. The averaged ontogenetic spectrum ofA. biarmiense in the mountain-tundra belt is sinistral ancipitous with a maximum in virginal individuals (25,1%), the second peak is in mid-age generative individuals (21,1%); in the mountain-forest belt it is sinistral unimucronate, absolute maximum - in virginal individuals (37,4%). The age structure of concrete coenopopulations of A. biarmiense has two types of spectrum: sinistral and centered. Assessment of age Δ (delta) and efficiency ω (omega) has shown that all coenopopulations of A. biarmiense are young (Δ = 0,11-0,26; ω = 0,33-0,58). Comparison of indices of restoration and aging, reflecting dynamic processes of coenopopulations was carried out. Index of restoration fluctuates from 1,0 to 4,21. This fact testifies to good replenishment by young individuals and prevalence of pregenerative fraction. Index of aging is equal or close to zero that testifies to intensive dying off of individuals in old generative condition.