Vol 11, No 2 (2018)

This article considers the patterns of correlations between the topography and spatial organization of the landscapes of two hierarchic levels (stows and groups of stows). A number of basic topographic parameters that are most significant for landscapes are obtained according to the digital elevation model of the basin of a minor river using geoinformation methods. The correlations are revealed using discriminant analysis. The greatest contribution to the discrimination of landscape units is made by the elevation. The directional slope is more significant for the discrimination of stows, while the standard deviation of slope is more significant for the discrimination of groups of stows. The latter parameter in combination with the profile curvature, as well as the wetness index, are significant for extracting valley geosystems. The same method was used to analyze the air temperature during the vegetation period as a factor that differentiates the conditions of the location of landscape units. The valley geosystems are grouped as colder ones, while the pyrogenic site is grouped as that with the highest amplitude of temperatures.

Morphostructural features of aerial parts of shoots have been studied in endemic Hedysarum austrosibiricum B. Fedtsch growing at the altitude range of 1200–2350 m in the mountain areas of the Altai Republic (AR) and the Republic of Khakassia (RK). A complex of morphological traits adaptive to mountain conditions has been revealed in the studied species. A reliable trend to the reduction of a leaflet size in compound leaves and the number of inflorescences per shoot has been observed. Under mountain conditions, this species demonstrates a tendency to a significant productivity increase manifested via an increase in the caudex diameter and the number of shoots per plant. A low correlation between the values of most morphological traits related to plant growth and development may be considered an adaptive feature of the studied species.

The regularities that shape the composition of low molecular weight organic compounds (LMWOCs) in aquatic macrophytes in response to aquatic environment alterations remain poorly characterized. The aim of the present study consists of a comparative interannual investigation into LMWOC composition in rigid hornwort (Ceratophyllum demersum L.) from a Volga-Akhtuba floodplain lake with a variable trophic state. A high variability of LMWOC composition and individual compound levels in hornwort is detected as different trophic states of the water body are analyzed. Active allelochemicals are the predominant LMWOCs in the case of a “macrophytic” mesotrophic state of the lake, with fatty acids (the free fatty acid fraction) apparently being the most important in this group. Hornwort LMWOC composition in the case of a “cyanobacterial” eutrophic type of lake development is characterized by the predomination of compounds that enhance the protective reactions (manool being the most important) under the conditions of suppression by cyanobacteria, which is also manifested as an almost twofold decrease in the overall intensity of organiccompound biosynthesis.

The dynamics of the fatty acid (FA) composition of total lipids in needles of Siberian spruce (Picea obovata L.) during the first half (March–July) of the 2010 vegetation season has been studied. Three maxima of the unsaturated fatty acid (UFA) content with increased levels of α-linolenic acid are revealed in the postwinter (March 10–April 6), spring (April 20–May 18), and summer (June 1–July 20) periods. During postwinter and spring vegetation, the UFA increase is accompanied by an increase in the oleic and linoleic desaturation ratios. The spring peak of the 18:3ω3 content coincides with the spring peak in chlorophylls in the light-harvesting complexes of photosynthetic units and with the onset of the net CO₂ assimilation. The summer peak is characterized by the level of chlorophylls, which is the highest over the entire monitoring period. The possible ways that the FA is involved in the rearrangement of the structural and functional organization of the photosynthetic apparatus of a coniferous plant are discussed.

For the first time, the platinum accumulation levels and distribution patterns in the soil and in roots, stems, leaves, flowers, and seeds of medicinal herb Scutellaria baicalensis Georgi, Lamiaceae (Baikal skullcap) have been researched using the stripping voltammetry method. The plants were collected both in their natural habitats (southwestern part of Primorskii krai, Amur oblast, and Chita oblast) and from the S. baicalensis population introduced in the Central Siberian Botanical Garden (CSBG), Siberian Branch, Russian Academy of Sciences (Novosibirsk). In the habitats of S. baicalensis, the content of platinum in soils varies from 0.001 to 0.426 g/t. The content of platinum in various parts of the plants varies from 0.001 to 0.43 g/t. The platinum bioaccumulation factor in S. baicalensis individuals collected in various habitats varies from 0.01 to 6.1 g/t.

The Zagros and Alborz mountainous ridges can be regarded as one of the most interesting and known physical barriers responsible for the vicariance event. Based on the probable effect of Zagros Mountains on the rodent population vicariance, a research on Caucasian mole vole phylogeography, population genetic structure and diversity was designed along the mentioned mountainous areas. To this end, a total of 38 tissue samples were collected from the northern parts of the study area to the southern parts. Obtained mitochondrial cytb (1041 bp) sequences were used in this phylogenetic analysis. The phylogenetic analysis was based on the TRN+I evolutionary model and gaining Bayesian phylogenetic tree with maximum verification. By using median joining logic, the relationships between different acquired haplotypes were analyzed. It was shown that the Caucasian mole vole population had been disjointed (based on posterior probability of 1 and 100 bootstraps) along the Zagros mountainous ridges, especially in both geographical extremes located in the northern and southern parts of the mountainous ridges. Meanwhile from the 38 analyzed sequences, 17 haplotypes were obtained, of which 10 haplotypes were unique. The mutational steps between haplotypes were assessed by generating statistical parsimony haplotype networks, which yielded 36 mutational steps between the northern and southern populations. Based on neutrality tests and analyzing their power under sudden population expansions, it was found that this event happened around the northern and southern populations. Genetic distance of two percent between the northern and southern populations indicated the existence of local adaptations by these two groups, which can be regarded as evolutionary units.