BIOTOPIC FEATURES OF RUBUS CHAMAEMORUS (ROSACEAE) FRUITING IN HYPOARCTIC TUNDRA COMMUNITIES OF TAZOVSKIY DISTRICT OF THE YAMAL-NENETS AUTONOMOUS AREA
The paper presents the results on studying the productivity of cloudberry (Rubus chamaemorus L.) in the hypoarctic tundra communities of Tazovskiy district of the Yamal-Nenets Autonomous area. The research was carried out on 12 sample plots, along the meridional transect, covering the territory of the southern hypoarctic tundra and forest-tundra in the left bank of the Taz river. It is shown that the productivity of cloudberries is mainly determined by the biotopic features; the longitudinal dependence was not revealed. To assess the impact of biotopic characteristics on cloudberry yield, all sample plots were divided into several groups depending on their position in the tundra landscape, and by humidity and habitat security factors. The highest yield of berries (608.5 kg/ha on an average) was recorded in moderately humid habitats associated with the lower parts of slopes by tundra lakes, protected from wind and, to some extent, from sudden temperature fluctuations. The minimum yield (47.4 kg/ha) was observed in dwarf birch-dwarf shrub-sphagnum hummock tundra communities occupying the upper parts of hills and low ridges. Open peat hummock areas are characterized by the larger number of berries smaller in size and weight. A developed shrub layer leads to a decrease in the berries yield.