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In the diurnal lepidopteran fauna of the northern taiga subzone in the western Russian Plain, the species inhabiting primary biotopic complexes typical of this subzone currently account for slightly more than 60% of the total species richness and abundance. A large part of the fauna is represented by the species of more southern origin, whose expansion to the northern taiga was caused by anthropogenic transformation of landscapes between the 12th and 20th centuries and recent climate warming.  相似文献   
2.
The structure of bumblebee communities has been studied in some ecosystems of Kunashir Island and Southern Sakhalin. The island taxocenes include five to eight bumblebee species. Bombus hypnorum is dominant in the majority of habitats. In geothermal areas near hot springs on Kunashir, the families of this species develop more rapidly than in areas without geothermal heating.  相似文献   
3.
On the Solovetskiye Islands, subtundra forests and forest-tundra crooked forests are considered to be zonal biocenoses, as this region is intersected by the 12°C isotherm for July, which marks the boundary between the northern taiga and forest-tundra zones in northern Europe. The formation of extrazonal tundras on the islands is attributed to the cooling effect of the sea and the prevalence of cold northeasterly winds in the growing period. Herbaceous and herb-bilberry forests similar to their middle-taiga counterparts develop in this region due to a convective heat flow anomaly of high intensity (up to 40–50 W/m2). The phenomenon provides evidence for the existence of an active heat source in the crust under the archipelago. This source is probably a diapir fold involving the upward movement of the mantle.  相似文献   
4.
The main differences in the structure and species diversity of topical groups of mollusks between lakes on Solovetsky Island and continental lakes have been revealed. Insular groups are characterized by higher indices of species richness (the average number of species per sample) and density, with the level of dominance being decreased. In general, specific features of the insular territory impose limitations not only on the total species richness but also on the number of structural variants of topical mollusk groups, with the range of parameters of their species diversity being reduced against the background of sharp increase in the density of mollusk colonies. Insular topical groups of mollusks are characterized a certain set of species dominating in abundance.  相似文献   
5.
Main trends in the formation of biotopic complexes of bumblebees in the northern taiga zone are analyzed. It is proposed that Eurasian forest species of bumblebees (Bombus (Th.) schrencki, B. (Mg.) consobrinus, etc.) are coadaptively connected with entomophilous plant species belonging to the synusia of Eurosiberian riverine-mountain meadow tall herbage, with the numbers of species in both biotic groups (pollinating insects and plants) and their abundance being greater in the landscape characterized by a high degree of karstification. In the biotopic bumblebee complex of a large river valley, the relative abundance of forest bumblebee species is 2.5–5.3 times lower than in other complexes, whereas that of meadow species is two orders of magnitude higher due to favorable thermal conditions and a large number of habitats with mesophilic herbage and legumes. Each of the distinct ecogeographic groups of bumblebees and the corresponding synusiae (each comprising entomophilous plants of different taxonomic groups) appear to be coadapted. This is probably a result of the diffuse coevolution of pollinators and plants belonging to the genetically unified biota.  相似文献   
6.
Only two river basins in which the European pearl mussel has survived to date are known in Arkhangelsk oblast. These are the Solza and Kozha basins. The northeastern boundary of the European range of this species passes along the watershed between the basins of the Solza and the Shirshema (the Onega Peninsula) and then along the Onega-Northern Dvina watershed. The population density and the proportion of juveniles widely vary in different parts of the Solza Basin, and, therefore, the previously conclusion concerning the ageing of the population in the Kazanka River (Bolotov and Semushin, 2003) applies only to certain parts of this river. The highest density of the pearl mussel in the Solza Basin is 68 ind./m2. Fish cultivation contributes to the conservation of this pearl mussel population, as the release of Atlantic salmon juveniles ensures reproduction of the mollusk under conditions of regulated river flow.  相似文献   
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