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No 3 (2024)
Articles
Indication of radioactive contamination of forest ecosystems in the zone of the east Ural radioactive trace using methods of quantitative wood anatomy
Abstract
The anatomical structure of the annual rings of Scots pine, formed before and after the Kyshtym accident, is analyzed. In trees growing closer to the central axis of the East Ural radioactive trace (EURT), a decrease in the number of cells in the annual ring, as well as a decrease in the diameter of the lumens and the thickness of the cell walls, was noted. It is assumed that radiation-induced damage to the photo-assimilation apparatus of trees led to disturbances in physiological processes that were reflected in the anatomical structure of wood.
165-172
Tree stand structure in the forest–mountain steppe transition zone on the slopes of the Kraka massif (Southern Urals) and its determining factors
Abstract
Ground-based laser surveys of the upper parts (from the ridge crests to the border of closed forests) of six steppe slopes of the mountains of the Southern and Northern Kraka massifs (Southern Urals) on a total area of 20.82 hectares were carried out. As a result, 3584 trees were identified in all studied areas, their morphometric parameters (crown height and size) and exact geographical position were assessed with an accuracy of 3–10 cm. It was shown that the closure and density of tree stands are extremely low in the upper third of the surveyed altitudinal profiles, and a local increase in these indicators is observed only on some slopes. It is also widely noted that these characteristics of forest stands increase sharply at a distance of about 2/3rd of the length of the profiles from the ridge crests. Measurements of the depth of the soil layer showed that the soils in the upper parts of the slopes are thin (on average 7–12 cm), and their average depth reaches 29 cm only on some slopes in places where the density of forest stands increases. Soil depth on sections of profiles remote from the ridge crests 1/4th to 2/3rd of their length gradually increases and reaches average values of 20–30 cm. We associate both local and stable (in the lower part) increase in the density of forest stands in the forest–mountain steppe transition zone with the increase in the thickness of the soil layer and the volume of moisture retained by it.
173-184
Productivity of the Bakchar bog plant communities in the initial stages of pyrogenic succession (southern taiga of Western Siberia)
Abstract
The results of a study on the productivity of plant communities after a crown fire in a drained oligotrophic bog in the southern taiga of Western Siberia are presented. A quantitative assessment of biological productivity in areas with varying degrees of pyrogenic disturbance is given. The reserves of the grass-shrub and moss layers in the most disturbed area in the second year of restoration amounted to 1220 g/m2, production was 324 g/m2 per year; in the third year, reserves increased to 1635 g/m2 and production increased to 1038 g/m2 per year due to the growth of blueberries, while the production in the control site with high reserves of living phytomass (2200 g/m2) amounted to 745 g/m2 per year. There was a change in the structure of the phytomass, compaction of the deposit by 34%, and an increase in the mortmass of vascular plants by three times. The living mass of roots in the disturbed area concentrated in the upper layer of 0–10 cm, while it was distributed in the control area in the layer of 10–30 cm. It was found that the roots of dead pines retain the morphological characteristics of living ones during the first two years and pass into the fraction of dead roots on the third year of pyrogenic succession. Carbon losses during burning of the top layer of tow up to 20 cm amounted to 3016 g C/m2, 500 g/m2 of which can be buried as a layer of coal in peat.
185-197
Effect of chemical pollution on the fertility of male rodents from natural populations: сomparing the response of sperm morphology, motility, and concentration
Abstract
The results of studies of epididymal spermatozoa of three species of rodents (bank vole Clethrionomys glareolus, northern red-backed vole Cl. rutilus, and herb field mouse Sylvaemus uralensis) living under long-term exposure to atmospheric emissions from two large copper smelters in the Middle Urals are summarized (Middle Ural and Kirovgrad copper smelters). The impact of pollution (including at the individual level on the accumulation of Cu, Zn, Pb, and Cd in the liver) was assessed for indicators characterizing the quality of sperm from different aspects: morphology (proportion of cells with head and tail defects), motility (proportion of motile cells, velocity, and straightness of movement) and concentration. Sperm motility responds to pollution: in impact zones, the proportion of motile cells and their velocity were lower than in background zones. The occurrence of abnormal cells and sperm concentration were not statistically significantly different between impact and background zones. The reaction of sperm to chemical pollution is species-specific: voles react more strongly than the herb field mouse. The consistency of changes in sperm parameters (in the direction of their deterioration) in response to increased pollution was found only in the bank vole. Effect sizes for sperm parameters are much smaller compared to those for liver Cd accumulation and animal abundance. In general, the reaction of sperm to pollution turned out to be weak, none of the studied indicators can be a reliable marker of industrial pollution.
198-216
Macrozoobenthos of subarctic lakes as an indicator of climate change
Abstract
Changes in the macrozoobenthos of two northern lakes differing in degree of humification of water over the 50-year period that have passed since the first studies were considered. In the lake with water uncolored by humus, the benthos biomass increased, and in the humified one, it decreased. The changes that have occurred are due to climate warming, especially pronounced in winter. It was concluded that even closely located bodies of water can respond differently to climate change. Depending on the nature of the catchment area and the morphology of the lakes, either an increase in their productivity due to the supply of nutrients or a decrease due to humification can be observed.
217-226
Proportion of birch leaves damaged by insects along the pollution gradient of the Middle Ural copper smelter
Abstract
The proportion of leaves of downy birch (Betula pubescens Ehrh.) damaged by insects at ten sites of coniferous forest along the pollution gradient of the Middle Ural copper smelter was analyzed. The study was conducted during periods of moderate (2009) and low (2019) emissions in early and late summer. The proportion of damaged leaves was higher in 2019 and increased towards the end of the growing season but was not associated with distance to the smelter and lead concentration in leaves.
227-232
Distribution of striped cancer Faxonius limosus in water bodies of Belarus
Abstract
Faxonius limosus (Rafinesque, 1817) was first discovered in the rivers of Belarus in 1997. The striped crayfish spread along rivers originated in Poland. Currently, F. limosus is found in the Neman River and in all tributaries of the first and second orders within the borders of the Grodno region and the rivers of the Western Bug basin of the Brest region of Belarus. The striped crayfish colonizing new places moved upstream of the rivers: the maximum speed of spread was 20 km/year, and the average speed was 7–8 km/year. Males of older age groups appear first in new habitats. As a result of human activity, the migration of striped crayfish from the Neman basin to the Dnieper basin has been noted.
233-240