Vol 47, No 5 (2016)

An analysis is made of the effect of large spruce and birch trees on the spatial pattern of the fields of heavy metal concentrations (Cu, Pb, Cd, Zn) and pH in the forest litter formed in tree stands exposed to long-term pollution with emissions from the copper smelter in Revda, Sverdlovsk oblast. The fields formed by trees growing in the background area have a regular spatial structure: the concentrations of elements decrease with increase in the distance from the tree trunk to the edge of canopy gap, with the position of sampling point relative to the trunk accounting for more than half of total variance. In polluted areas, the regular component of the field structure is very weakly expressed, and the main role is played by higher-order heterogeneity related to the mosaic pollution pattern on the scale of tens to hundreds of meters.

Based on gradient analysis and indicator values, spring water chemistry and temperature and the dynamics of water level were shown to be the main ecological factors of plant cover differentiation in spring fens. Six groups of plant communities were identified by ordination along the axes of these factors, with each group being characterized by a certain suite of indicator species.

Determined the contribution of root derived CO₂ efflux to total CO₂ efflux (including root and non-root derived CO₂ efflux) is import to grope the mechanism of CO₂ efflux, however, becaused of ‘rhizoshere priming effect’ (RPE), it is difficult to achieve in practice. In this study, we attempted to estimate the RPE via comparing basal soil respiration (R_b) achieved by two different methods namely, y-intercept regression and direct bare plot approach in an arid cotton field, central Asia. On the basis of the y-intercept of linear regressions between below-ground respiration (BGR) and root biomass, R_b was indirectly calculated. Comparing with the first approach, the second approach involved direct measurements of soil respiration from bare plots. R_b estimated by y-intercept method contained the component of RPE whereas direct bare plot did not. We found that RPE showed a phenological trend with highest value in flowering stage at 0.145 g CO₂ m^–2 h^–1 and lowest at budding stage (0.007 g CO₂ m^–2 s^–1), even after the data had been corrected for the influence of soil temperature. We concluded that RPE needed to be considered when R_b was estimated by y-intercept approach.

Communities of benthic macroinvertebrates in drainless Lake Chany, the largest lake in Western Siberia, have been analyzed to estimate the effects of basic abiotic ecological factors (hydrophysical and hydrochemical parameters of water and the type of bottom ground) on their composition, structure, and dynamics. It has been shown that the level of development of these communities depends mainly on the water regime of the lake and also on the type of bottom ground, lake depth, and water mineral content.

Few studies exist on phenotypic composition of the sable populations in the Russian Far East, China and Japan. We present new data on the morphological diversification of sable for 20 mainland and island populations in an effort to document existing variability and produce baseline data that would be useful in constructing phylogenies for this species. Сlinal variability of skull size, cranial phene, foramen in fossa condyloidei inferior (FFCI), and fur coloration is revealed. One district, Central Sikhote-Alin, is characterized by sables with the minimum cranial size and the maximum phene expression. The area between the Uda River and Goryun and Amgun rivers is inhabited by sables of the darkest fur coloration. Moving out from those areas in all directions we were detected a trend of increasing skull size, reduction of cranial phene, and decreasing color intensity of fur. The skull size of sable is consistent with Bergmann’s rule. Special attention paid to the particular morphological properties of insular populations in specific climatic conditions and under isolation from the continent. They are characterized by minimal expression phene FFCI (Bolshoi Shantar, Iturup, and Hokkaido islands) and larger skull size, especially in sable of Kamchatka Peninsula. It is hypothesized that the area of the lower Amur Basin was a source of sable postglacial dispersal on the Eurasian Continent.