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The Khudosey River is the only tributary of the middle reach of the Taz River (Western Siberia) suitable for breeding and wintering whitefish in the conditions of natural suffocation, which continues annually from November to April. The reproduction of whitefish in the Khudosey River was investigated for the first time. They were carried out in 2002, 2003, and 2017–2022. The main spawning grounds of whitefish are described. It has been established that the downstream migration of larvae on the lower border of spawning grounds begins with the first rise of water and ends immediately before the floating of ice. A special natural factor was noted – frostbite from freezing of riffles in spawning grounds, causing the complete death of incubated eggs. There is a high potential for the Khudosey River in the reproduction of whitefish, comparable to the potential of the Ural spawning tributaries of the lower Ob. It was revealed that the increase in the level of reproduction of whitefish of the Taz River can occur due to the migration of fish from the Ob River. [ABSTRACT FROM AUTHOR]

Abstract—According to the data collected in the second half of summer for the period from 1954 to 2016 in the plain and mountainous parts of Western Siberia, the distribution and number of the narrow-headed vole in the zonal and provincial aspects were analyzed. Based on cluster analysis of the matrix of similarity coefficients of abundance indicators obtained by averaging the initial data by years and groups of geobotanical maps units, classification of habitats according to the degree of favorable environmental conditions for the vole is made. The averaged samples are divided into five types of favorability: from the optimal type, where the abundance of the species is highest in the whole area studied, to the extreme type, where it is not found. In the southern part of the West Siberian Plain, the narrow-headed vole prefers steppes, and in the subarctic tundra, it prefers communities of river valleys. In the Altai and Kuznetsk-Salair mountain regions, it is most common in the subalpine light forests, tundra, and tundra–steppes of northwestern and southeastern Altai. On average, this vole prefers open habitats in Western Siberia. According to the classification and the structural graph, the dependence of the vole abundance on a number of factors and their inseparable combinations (environmental and anthropogenic regimes) was revealed. The greatest relationship with its distribution in the habitats of Western Siberia is traced to heat and water availability. On the plain, the number of this vole increases from the middle taiga, where it was found only once, to the subzone of the subarctic tundra in the north and to the forest–steppe and steppe zones in the south. In the mountains it is most abundant in Southeastern Altai, where there is a relatively high proportion of the habitats that are most favorable for the narrow-headed vole. [ABSTRACT FROM AUTHOR]

Based on the analysis of materials collected for many years the dynamics of the moose's habitat and population numbers in West Siberia is described. For the southeast of the West Siberian part of the habitat the cohabitation of mooses with the haplotypes of both European ( A. a. alces L.) and East Siberian ( A. a. pfizenmayeri Zukowski) subspecies is demonstrated on the basis of investigation of the structure of the mtDNA D-loop hypervariable domain. High nucleotide (p) and haplotypic (H) diversity substantially exceeding corresponding indices for the moose in the European part of Russia and the Urals has been revealed. [ABSTRACT FROM AUTHOR]

The composition, biomass and pigments of the phytoplankton population below the ice cover in Lake Teletskoye were investigated in March 2006. It was found that the composition and biomass of phytoplankton below the ice remained the same throughout the year. Furthermore, the stability of the water column was more important for the development of the phytoplankton assemblage below the ice than was the water temperature and light intensity. Small flagellates and diatoms were abundant among the algae in the upper layers of the lake's water column. Lake Teletskoye is similar in its phytoplankton composition and algal distribution throughout the water column to large, deep temperate lakes and Arctic or Antarctic lakes covered temporally or perennially by ice. [ABSTRACT FROM AUTHOR]

Permafrost peatlands, containing a sizable amount of soil organic carbon (OC), play a pivotal role in soil (peat) OC transformation into soluble and volatile forms and greatly contribute to overall natural CO2 and CH4 emissions to the atmosphere under ongoing permafrost thaw and soil OC degradation. Peat microorganisms are largely responsible for the processing of this OC, yet coupled studies of chemical and bacterial parameters in permafrost peatlands are rather limited and geographically biased. Towards testing the possible impact of peat and peat pore water chemical composition on microbial population and diversity, here we present results of a preliminary study of the western Siberia permafrost peatland discontinuous permafrost zone. The quantitative evaluation of microorganisms and determination of microbial diversity along a 100 cm thick peat soil column, which included thawed and frozen peat and bottom mineral horizon, was performed by RT-PCR and 16S rRNA gene-based metagenomic analysis, respectively. Bacteria (mainly Proteobacteria, Acidobacteria, Actinobacteria) strongly dominated the microbial diversity (99% sequences), with a negligible proportion of archaea (0.3–0.5%). There was a systematic evolution of main taxa according to depth, with a maximum of 65% (Acidobacteria) encountered in the active layer, or permafrost boundary (50–60 cm). We also measured C, N, nutrients and ~50 major and trace elements in peat (19 samples) as well as its pore water and dispersed ice (10 samples), sampled over the same core, and we analyzed organic matter quality in six organic and one mineral horizon of this core. Using multiparametric statistics (PCA), we tested the links between the total microbial number and 16S rRNA diversity and chemical composition of both the solid and fluid phase harboring the microorganisms. Under climate warming and permafrost thaw, one can expect a downward movement of the layer of maximal genetic diversity following the active layer thickening. Given a one to two orders of magnitude higher microbial number in the upper (thawed) layers compared to bottom (frozen) layers, an additional 50 cm of peat thawing in western Siberia may sizably increase the total microbial population and biodiversity of active cells. [ABSTRACT FROM AUTHOR]