Home – Home – Jornals – Contemporary Problems of Ecology 2026 number 3

The theory of geographic parthenogenesis initially described differences in the territorial distribution of sexual and parthenogenetic forms of animals, but then it was extrapolated to apomictic plants. It was argued that apomicts differ from their sexual relatives by larger ranges, preferential distribution in northern latitudes and at a high altitude. New information on the geographic distribution of sexual and apomictic species has been accumulated in recent decades. An analytical review of these data is given in this article. It is shown that the distribution of apomicts does not always agree with the above trends, and some of apomicts even demonstrate opposite trends. Belonging to the same genus does not guarantee the same patterns of distribution of apomicts and amphimicts. The most controversial position of the theory of geographic parthenogenesis is the assertion that apomictic plants are attracted to high altitudes. Possible prerequisites for the specific geographical distribution of apomicts are discussed. It is suggested that the reasons for the lack of uniform trends in the territorial distribution of apomicts and related amphimicts may be different ways of mode of apomicts origin and their evolutionary age, the diversity of apomixis types and limiting factors that plants encounter during dispersal.

The article presents a new tree-ring network of chronologies for Scots pine and Siberian larch for the Republic of Khakassia. The key difference compared to previous researchers who had previously constructed two chronology networks for the region under consideration is the establishment of trial plots in the rain shadow on elevated habitats (hill slopes, cuestas) on the western border of the Minusinsk basins. Analysis of the main statistical parameters of the new chronology network showed that, with the exception of first-order autocorrelation, there are no significant differences between the two tree species. Based on the results of cluster and correlation analyses, regional chronologies for Scots pine and Siberian larch were obtained (by generalizing local tree-ring chronologies). Verification of the new network with previously published chronologies for the study area showed that some of them contain obvious errors. The use of such chronologies without corrections for paleoclimatic reconstructions, dating of materials from historical buildings, etc. may lead to distortion of research results. Of no less importance is the use of modern (digital) methods for measuring tree-ring parameters to improve the quality of tree-ring chronologies. The fact that even the most distant chronologies (up to 230 km in a straight line) for different tree species are in good agreement with each other in the future will allow us to significantly expand the dendrochronological network by including new areas (primarily pine forests of the Republic of Tyva and Krasnoyarsk Krai). In the future, this can significantly increase the existing potential of pine and larch forests in the south of Siberia for conducting a comprehensive analysis of the growth of woody vegetation in the forest-steppe over the past millennium and performing paleoclimatic reconstructions.

The article discusses the diagnosis of the environmental situation in the affected area of the Karelian Okatysh iron ore mining and processing plant (Republic of Karelia), based on changes in the width of annual tree rings and the chemical composition of wood (Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, Sr, Ti, V, and Zn) of Pinus sylvestris. Geoecological studies were conducted on the plant’s territory in Kostomuksha and on background monitoring stations in the Kostomuksha Nature Reserve. Radial growth is limited by air and soil temperatures, precipitation, evaporation throughout the year, and, in particular, during the growing season. Edaphic factors manifest themselves through a decrease in radial increments with increasing content of poorly decomposed organic matter in soils. Since the start of the construction of the plant in 1978, climatic and edaphic conditions in the impact area have been affected by anthropogenic factors related to aerotechnogenic emissions of Fe, K, V, Ni, Zn, Mn, Co, Cd and Cr. The chemical composition of wood is mainly influenced by the underlying rock composition, with the ore components Fe-Mn-V-Ni-Cr-Ti being present in the area of the plant. In the period 1978_-2023, parageneses of Mg-Sr-K-Ti-Zn-Ca-Ba reflect pollution from mining activities, while Mn-Cd-Zn is linked to vehicle emissions. Dendroindicators reflect local environmental transformations near production sites, quarries, dumps, tailings, railway tracks, and pulp pipelines. In Kostomuksha, pollution is also noted along highways and intersections. The integral bioindication parameter BIP, based on the Harrington desirability function, indicates a relatively favorable state of organisms and a low level of disturbance. The effectiveness of dendroindication and BIP for environmental assessment has been demonstrated.

This paper presents the first results of tracking the autumn migration of adult Slaty-backed Gull (Larus schistisagus) using GPS-GSM loggers from a breeding colony in the northern Sea of Okhotsk (Tauyskaya Bay) to the wintering region (Hokkaido Island). The migration distance (2.6-4.3 thousand km) classifies the Okhotsk Sea population as “long-distance migrants.” Like other large white-headed gulls, Pacific Gulls employed a “fly-and-forage” migration strategy during autumn, with significant variation in routes and individual travel tactics, utilizing individual experience in selecting stopover sites. The gulls preferred coastal migration routes and exhibited flexible travel behavior. Both birds used overland and open-sea crossings to shorten their path and were active during the day and at twilight. The autumn migration of Pacific Gulls was characterized by a low overall migration speed, a close trophic association with Far Eastern salmon, and the use of anthropogenic food sources - following fishing vessels and utilizing fish processing waste and food scraps in settlements.

Based on materials gathered during late summer periods from 1954 to 2016 across the plains and mountains of West Siberia, we analyzed the zonation and provincial aspects of common vole (Microtus arvalis) distribution. Overall, the species is abundant throughout the region. On the West Siberian Plain, it prefers open and often cultivated habitats. In the forest-steppe zone, especially in steppe landscapes where its numbers peak, it shows preference towards partially flooded and swampy biotopes. Across the mountainous territories of West Siberia, Microtus arvalis predominantly inhabits open and less frequently mosaic lowland biotopes, particularly in agricultural lands and urbanized environments. Cluster analysis of abundance coefficients resulted in five categories of habitat suitability: optimal, sub-optimal, sub-pessimistic, pessimistic, and extreme (where the species was not detected). This classification established correlations between spatial heterogeneity of species abundance and environmental factors and their combinations (modes). For the common vole, three groups of environmental gradients can be distinguished related to its spatial distribution: thermo-hydrological conditions (including variations in heat and moisture ratios within different zones and provinces); vegetation-related gradients (vegetation type, degree of woodedness, tree composition); and local impact factors (agricultural land use, wetlands, floods, human settlement presence).

The purpose of the study was to conduct histological and morphometric research on kidney tissue in small mammals inhabiting the Norilsk-Pyasinsky ecosystem. Three locations were identified at different distances from the industrial sites of the Norilsk mining and metallurgical complex. Thirteen mammals were captured at three sites, including 10 males and 3 females. Kidney tissues of wild mouse-like rodents were studied. Histological and morphometric methods were employed in the research. Hematoxylin-eosin was used for staining the histological sections of the kidneys. The following morphometric parameters were determined in the kidney histological section: 1) percentage of non-sclerotic renal glomeruli (%); 2) percentage of sclerotic renal glomeruli (%); 3) total area of glomeruli (μmІ); 4) total area of the capillary network of the renal glomeruli (μmІ). The database was created in Microsoft Excel. Statistical processing was carried out using the “Statistika 10.0” program. Reliable data was obtained indicating structural pathomorphological changes in the kidney tissues of rodent-like animals inhabiting the studied areas. During the study, a pattern was revealed: the closer the habitat area is to industrial enterprises, the higher the percentage of sclerosed renal glomeruli against a background of a low number of functioning nephrons. The identified pathological disorders led to the development of renal failure in organs with varying degrees of severity, resulting in reversible (dystrophic) and irreversible (necrotic) changes depending on the habitat of the animals. The specificity of the changes in the kidneys of the animals may be the result of the action of exogenous intoxications (poisoning) in the inhabited areas.

In the floodplain landscapes of the Norilo-Pyasino lake-river system along the line the Daldykan River - the Ambarnaya River - the Pyasino Lake - the Pasina River - the Kara Sea changes in the alluvial soils properties were studied, specifically the content of chemical elements (N, P, K, Ca, Mg, Na, Fe, Mn, Zn, Cu, Co, Mo, B, S, As, Cd, Cr, Ni, in soils and plants of the Carex, Salix, Eguisetum genera and the Poaceae family. Natural factors were found to determine the difference between soils in granulometric composition, increased Cu, Ni and Co in soils and plants, surplus Fe and Mn and insufficient P, Zn and Mo in plants. The impact of technogenic contamination of the floodplains of the Daldykan, and Ambarnaya Rivers up to the Pyasino Lake was proven to increase soil acidity and total Cu, Ni and Co content, as well as the concentration of the mobile forms of soil S-SO4, Ni, Cu, Co, Cr. Due to the changes in the contaminated soils composition and properties, plants accumulated Cu, Co and B in excessive and Ni in toxic for plants and animals concentrations. Both natural and technogenic factors determined the increased, as compared with their Clarke number, content of As, Cd, Hg, Pb in plants, but not exceeding the maximal permissible concentrations in forage plants, and decreased plant P, Ca, Zn, Mo content, making it insufficient for the normal supply of the elements to agricultural animals. Since in the West Taimyr area the share of territories with technogenically contaminated soils and plants is not large, their negative effect on the reindeer diet will not be significant.

The dynamics of the abundance and distribution patterns of mycelial fungi, yeasts and bacteria were studied in the soil of a bilberry-sphagnum birch forest in the Yaroslavl region, taking into account the biogeochemical background, and the contribution of fungi and bacteria to the net ammonification process was determined using inhibitor analysis. Bacteria were predominant in the birch forest soil (43.5-98.7 %), while the mycobiota included fungi of the genus Penicillium (1-80 %) and yeast (0-88 %). A relationship was established between the abundance of all groups of microorganisms and pH; mycelial fungi with the content of Corg and NН⁺₄, the C/N ratio and C-CO₂ emission; yeast with soil moisture. The dynamics of the numbers of fungi, yeasts and bacteria in the upper soil horizon were close and negatively correlated with seasonal changes in ammonification ( r = -0.86 - -0.97). In the At1 horizon, the contribution of fungi to ammonification prevailed over bacteria, 208 ± 5 and 121 ± 3 mg N/100 g. In the peaty layer (A_t2 horizon), a slight predominance of fungal activity over bacteria was noted 98 ± 4 and 72 ± 4 mg N/100 g. In the eluvial part of the profile (A₂ horizon), a similar contribution of these groups was obtained 8.7 ± 0.4 and 9.7 ± 0.5 mg N/100 g.

This is the first report on the algae and hydrochemical composition of the Kholchuktug mineral spring, located in the Sut-Kholsky District of the Tuva Republic. According to the classification of therapeutic mineral waters based on temperature, it belongs to the cold group, and according to the degree of mineralization, it belongs to the low-mineralization group. The identified species composition of algae is represented by 72 species belonging to 35 genera and 21 families from 4 divisions: Cyanoprokaryota - 5, Bacillariophyta - 53, Chlorophyta - 2, Charophyta - 11. Seven dominants were identified, of which Meridion circulare, Diatoma mesodon, Ulnaria ulna stand out. The species composition is dominated by diatoms. An ecological and geographical analysis was conducted, according to which the source is dominated by benthic species with a predominance of indifferent forms in relation to halobity and active environmental response. 56 species were identified in the studied water flow as indicators of water saprobity. The predominance of xenobionts, oligobionts, and betamesosaprobionts was noted. Geographically, cosmopolitan and boreal species were dominant.

The concentrations of organophosphate flame retardants in the environment are rising due to the increasing volume of their production and usage. Trichloropropyl phosphate (TCPP), which is an organophosphorus ester (OPE), can be found in air, water, and soil. A significant amount of OPEs enters reservoirs. Aquatic plants have been understudied in terms of their ability to accumulate organic esters. Meanwhile, plants are an important primary link in trophic chains. They play a significant role in the transformation and migration of organic compounds within ecosystems. The accumulation of TCPP in three species of aquatic plants - Lemna minor L., Ceratophyllum demersum L. and Elodea canadensis Michx - was studied experimentally at initial ether concentrations of 100, 500, and 1000 ng L^-1. All plants accumulated TCPP. The maximum accumulation coefficient (BCF) was determined for all studied species at the lowest concentration of TCPP (100 ng L^-1). In water with higher concentrations of TCPP, the BCF values decreased. With a tenfold increase in TCPP concentration, the BCF value decreased the least in C. demersum (by 17 %) and decreased significantly in L. minor (by 72 %). The accumulation coefficient of E. canadensis was 40 % lower at 1000 ng L^-1 of TCPP in water compared to 100 ng L^-1. The bioaccumulation potential of C. demersum showed little change depending on the concentration of TCPP. C. demersum accumulated 9-13 % of the TCPP that was originally in the water. It is suggested that the uptake of OPEs by aquatic plants depends on the type of plant and the ability of organic compounds to penetrate not only through the roots, but also through the shoots that are completely submerged in water.