Home – Home – Jornals – Contemporary Problems of Ecology 2026 number 4

The role of rare bird species in the avifauna of the northern Central Siberian Plateau is analyzed using the Putorana Plateau as an example. The route census method was used. From 1958 to 2023, 172 encounters of 64 rare and vagrant species were recorded at 21 locations on the Putorana Plateau. The locations ranged from 100 to 1900 km from the known northern boundaries of their ranges, with an average distance (n = 58) of 600 km. Vagrant bird visits by 25 species are also known north of the Putorana Plateau - in the forest-tundra and tundra of Taimyr and the Anabar Plateau. Passeriformes and Charadriiformes predominate by number of species, together accounting for 58 %. The vast majority of encounters were recorded from June 1 to August 31. The most significant are widespread and boreal species, together accounting for 74 %. The role of boreal-hypoarctic, nemoral, nemoral-steppe, forest-forest-steppe, steppe-forest-steppe and alpine species is secondary, their combined share being 26 %. Of the species found outside the known boundaries of their nesting ranges, 1-13 encounters were recorded, with an average of 3 (n = 64). Species were recorded at 1-9, with an average of 3 (n = 64) points. At various points on the Putorana Plateau, 1-17 species were noted, with an average of 7 (n = 21), and 1-21, with an average of 8 (n = 21) registrations, were recorded. The number of rare and vagrant species decreases from west to east by 2,2 times, while the number of their registrations decreases by 2,5 times. In the western half of the region, the number of rare and vagrant species decreases by a factor of five from south to north, while the number of their registrations decreases by a factor of four. Birds vagrant are an integral component of the formation of biodiversity in the mountainous regions of the northern Central Siberia and the transformation of avifauna in the face of environmental change.

For the first time data of the study on the number and distribution of birds in the Upper Vychegda basin, which were conducted in June 2019, are presented. During the boat routes, the bed of the Upper River (from the Voldino Village to the Myel′dino Village) with a length of 140 km, and its tributaries (the Timshor and Mylva rivers) were studied. During the stops, pedestrian routes were conducted in various biotopes. The characteristics of the population density and abundance of birds in various habitats of the surveyed area are given. According to the results of the work, 123 bird species belonging to 11 orders were noted in the upper course of the Vychegda River. The following density and species abundance of bird population were recorded in the surveyed biotopes: floodplain meadows - 302 individuals per 1 km² (52 bird species), floodplain spruce-birch forest - 202 (39), swamps with pine forests - 66 (15), pine burnt-out areas - 29 (6), pine forest - 136 (18), Vychegda River floodplain - 54 (52), Timshor River floodplain 265 (14). Among the leaders most often noted are: Chaffinch, Common Sandpiper, Sand Martin and Tree Pipit. A high Shannon index was noted in the ecosystems of floodplain meadows and riverbed spruce-birch forests and the Vychegda River channel. The dominance index increases in ecological communities of moss-shrub swamps and pine burnt-out areas.

Patterns of relation between environmental filtering and competition, structuring assemblages of ecologically similar rodents, remain unclear. Thereupon we studied population density of mice and voles of Prikhanakaya Plain. We find their population variability limits describing habitat preferences. It was shown that populations of the harvest mouse, the gray red-backed vole and the northern red-backed vole, and also probably the Korean field mouse and the stripped field mouse, depend on warm-/humidity-supply, while their competition don’t influence structure of the rodent assemblage studied. We discuss its functioning mechanism and probable transformation trends through global change.

Despite the abundance of visual data, the influence of hydrological and hydrochemical factors on the phytocenoses of the coastal vegetation of the White and Barents Seas has been poorly studied. The article uses non-metric scaling to demonstrate that the coastal vegetation communities are heterogeneous and tend to be associated with specific habitats based on their composition and structure. The coastal vegetation communities are influenced by a complex of factors related to the aquatic environment. Tides, storm surges, salinity, and pH levels have the greatest impact on the formation of coastal vegetation. Of these, tides and storm surges are the leading factors in the formation of phytocenoses of different types of marshes. Surfing has a significant impact on the formation of beach plant communities. The author’s classification of hydrological and hydrochemical factors affecting coastal phytocenoses is presented.

The article presents the results of studies of the chemical composition of the waters of pit lakes formed after the development of the Zavitinskоyе lithium-beryllium and Zhipkoshinskоyе antimony deposits in the Trans-Baikal Territory. Data on the physico-chemical parameters of quarry waters, as well as the concentrations of macro- and micro components and their changes with depth were obtained. It has been established that the waters of the pit lakes are neutral and slightly alkaline, mainly of sulfate, sulfate-bicarbonate, and bicarbonate-sulfate magnesium-calcium type with abnormal concentrations of Li, Sr, and Ve in the reservoirs of the Zavitinskоyе, Sb, and As - Zhipkoshinskоyе deposits. Currently, the mines are closed, and the pit lakes, in particular the Zavitinskоyе deposit, are actively used by the population of nearby villages for recreation and fishing. In this regard, the contents of some components in quarry waters have been determined relative to the standards of maximum permissible concentrations of substances established for fisheries and drinking water bodies. The first data on phytoplankton, macroalgae and macrophytes, as well as zooplankton from man-made reservoirs of the above-mentioned deposits, were obtained, and their species and quantitative composition were determined. Low species diversity and low density of planktonic fauna and macrophytes were noted, which is due to the lack of biotopes for the development of diverse communities due to the limited catchment area, the steepness of the quarry walls, and, as a result, the absence of shallow waters with aquatic vegetation.

This manuscript examines the microbial transformation of persistent polycyclic aromatic hydrocarbons (PAHs) and their low-molecular-weight representative, phenanthrene, during the interaction of groundwater and river water. Experimental studies have shown that phenanthrene transformation in the riverbank filtration zone occurs at different temperatures (23 °C and 4 °C) and depends on the adaptive potential and physiological characteristics of microbial complexes (MC). Phenanthrene transformation products were determined with use of spectrophotometry (UV-3600 Shimadzu, Japan) and gas chromatography (Crystal-5000.1, Russia). Maximum microbial activity at 23 °C observed in samples taken from a well, located 50 m from the riverbank in the upper aquifer. MC become more active in groundwater in the lower aquifer at 4 °C. Phenanthrene transformation accompanied by a change in the color of the experimental fluid and the formation of slimy biofilms. According to the spectral characteristics of phenanthrene transformation products, maximum changes observed in its aliphatic component of the molecule at a temperature of 23 °C with the participation of MC from the upper aquifer, 50 m from the riverbank. The formation of aromatic components during phenanthrene transformation recorded in the lower layers of the aquifer at depths of 35 and 50 m at different distances from the riverbank filtration zone. At low temperature (4 °C), the behavior of groundwater microbial complexes varied depending on the sampling depth and corresponded to the adaptive potential to temperature in situ. The maximum activity of microbial phenanthrene transformation, relative to its aliphatic, aromatic, and chromophore components, recorded in deeper layers of the aquifer (25 m and 35 m). Regardless of temperature, toxic organic substances (isopropanol, isobutanol, acetone, hexane, methylated benzene derivatives) identified among the phenanthrene transformation products, which can affect the quality of groundwater and create problems in water treatment.

Moss Sphagnum fuscum and lichen Cladonia stellaris bags were exposed for 8 weeks in the Novy Urengoy municipality, after which their chemical composition was studied. Electron microscopy revealed the presence of rock-forming mineral inclusions and heterogeneous solid inclusions of various origins in the samples, including the ore minerals pyrite, sphalerite, galena, argentite, atacamite, cobaltite, ilmenite, and rutile (anatase); barite; native iron; fine particles of antimony, mercury, silver, and gold; Fe-Cr-Mn, Fe-Mn, Fe-Cr, Fe-Ti-Mn, Ti-Fe, and Ni-Cr-Fe alloys; Cu-Zn, Cu-Ni, Cu-Ni-Zn-Mn, Cu-Hg, Cu-Sb, and Cu-Sn; titanium plates; and microplastics. The western part of the municipality are characterized by low pollution levels, while in the eastern part, Cu, Ni, and Zn emissions from Norilsk enterprises are recorded. In the southern part of the city, pollution of Ca, Cr, Fe, Cd, Mg, Mn, Pb, V, and Zn were detected; in the north, emissions of Ba, Ca, Cd, Cr, Mg, Mn, Ni, and Sr were noted. Trends in metal accumulation by bags and epigeic lichens in various functional zones of the city are similar; however, bags had better accumulate elements that are poorly absorbed by plants during passive biomonitoring (K, Ca, Na, Ba, Cd, Cu, Mn, Ni, Pb, Sr, and Zn). The bioindication integral parameter BIP based on the Harrington desirability function confirmed the low level of pollutant input and the leading role of transport, as well as locally the airport and railways, in polluting the urban environment. The use of active biomonitoring methods in Arctic cities is recommended. The combined use of several transplant species is preferable, as Sphagnum fuscum better accumulates Ca, Cd, Cu, K, Mg, Mn, Sr, and Zn, while Cladonia stellaris accumulates Ba, Cr, Na, Ni, and Pb. The use of contamination factors is indicative for comparing pollutant accumulation by different species.

The microbiome, enzymatic activity, microbial biomass carbon, and cellulose decomposition are characterized in the main soil types of the southern Vitim Plateau and the Selenga Middle Mountains. The quantitative and qualitative parameters of microbial communities in various soil types in Western Transbaikalia are characterized. It was found that the abundance of bacteria, actinomycetes, and fungi, as well as enzymatic activity, are closely related to organic carbon (C_org) content, temperature, and soil moisture (r = 0.63-0.99). The highest bacterial abundance and maximum C-biomass values were observed in burozems and humus-hydrometamorphic permafrost soils, characterized by high Corg content. Significant biomass of actinomycete and fungal mycelium was found in dark gray neopodzolized soils. The lowest levels of prokaryotic microorganisms are characteristic of chestnut soils and fine-carbonate chernozems due to their low Corg content and moisture deficit. Catalase intensity varied from low to medium, and its activity varied from 2.9 to 10.8 ml O₂ (1 g/3 min), reaching a maximum in the humus pockets of burozems and a minimum in fine-carbonate chernozems. The highest values of invertase activity are characteristic of burozems and their humus pockets, and the lowest values are characteristic of fine-carbonate chernozems. Soil cellulolytic activity varies from a minimum (21 %) in fine-carbonate chernozems to a maximum (78 %) in quasigley chernozems. The new data obtained can provide insight into the stability of the microbiome in the studied soils of the region. The research results suggest a significant difference in biological activity between permafrost-affected and long-term seasonally frozen soils and highlight the importance of organic matter as a key factor in shaping soil biological activity.

The present work investigates the correlations between the concentrations of 40 chemical elements in soil (0-5(7) cm) and in Betula pendula Roth bark. Samples were collected in transport and recreational areas of Kirov city, Russia (taiga zone, temperate continental climate). Pollution indices (PI) were calculated by comparing the element content in the upper continental crust with that in the soil samples. The following series of elements with PI > 1 were established: Ag (4.91) > Cd (3.44) > Pb (3.16) > Sb (3.38) > Zn (2.19) > Ni (2.14) > Cu (1.69) > As (1.16) for recreational areas and Ag (2.97) > Cd (2.87) > Sb (2.11) > Cu (1.34) > Zn (1.28) > Pb (1.09) for transport areas. Birch bark accumulated most of these elements (PI>10): Zn, Cd, Ag, Cu, Sb, Pb, Ni, Hg, Mn, Mo, Sn, Bi, Cr. Cluster analysis was applied to the data. Soil elements were divided into two groups: metals associated with anthropogenic activity and rare earth/noble metals, which are not typical of urban environments. A strong correlation was shown between some biogenic elements and potentially toxic metals Na and Zn (r = 0.68), P and Cd (r = 0.98), P and Pb (r = 0.99), Ca and Tl, Cu, Ni (r = 0.95 to 0.998). Thus, Ag, Cd, Pb, Sb, Zn, Cu, Ni, As were classified as pollutants that accumulate in the soil for a long time and may migrate to plants. Indicators of recent anthropogenic pressure include Hg, Mn, Mo, Sn, Bi, and Cr. Further monitoring should focus on Sc, V, Co, Zr, Ba, Hf, Ga, Rb, Ta, Be, Tl, Nb, Li, and Cs, as their concentrations correlate with both biogenic elements and pollutants.

We studied the ecological, floristic, physiological, and biochemical characteristics of plants in carbonate substrates of the Zhiguli Mountains, one of Russia’s unique botanical and geographical regions. All species are confined to the cenoses of petrophytic steppes in two different biotopes, but differ in their geographic distribution. Five of them represent Middle and Lower Volga-South Ural species, three are endemic to the Zhiguli Upland, two are Southeast European species, and one each represents the groups of East European-Asian, South European-Central and Central Asian, and European-Asian species. Plants have various life forms: perennial herbs, subshrubs, and shrubs. They are obligate and facultative calciphytes with respect to the soil substrate. The biomass and architecture of leaves, pigment content, membrane complex indicators and elements of antioxidant systems were determined as parameters characterizing the structural and physiological-biochemical properties of calciphytes. We established the differentiation of plant groups depending on the soil substrate (facultative/obligate species), zonal-geographical element, life form for all measured characteristics. To clarify the reasons for the differences, we compared the variability of individual variables across different ecological groups. It has been established that calciphyte plants of the Zhiguli Mountains represented by various taxa and ecological groups, are capable of using complementary adaptation strategies to carbonate substrates. The adaptation of obligate calciphytes to the growing conditions of a given region is achieved through lower leaf density, less susceptibility to oxidative processes, and more effective antioxidant protection. These properties are especially evident in the endemic species of Zhiguli. The greater involvement of phenolic compounds, sugars, and proline in protecting against oxidative stress can be considered as one of the possible reasons why endemics thrive in certain local environments.

The content of heavy metals (HM) in the soil, foliage and shoots of wild raspberries (Rubus idaeus L., 1753) was studied in the area of 24 km of Yaroslavskoye highway (highway M8): a highway with heavy traffic. The selection of soil samples and biomaterial was carried out at a distance of 100-150 m. The content of Fe, Cu, Zn, Ni, Cd, Sr, Pb, Cr, Co, As, U, Cs, Sn, and Hg was determined in the samples. The biological absorption coefficient of HM (CBA) was calculated. An inductively coupled plasma mass spectrometer, PlasmaQuant MS Elite S-NR:11-6000ST043 (Austria), was used in the work. The soils were characterized by a high content of Fe, Cd (hazard class 1) and Sr (hazard class 3). Relative to Cd, the maximum permissible concentration (MPC) was exceeded by 1.8 times (3.59 ± 0.09 mg kg^-1). A case of hyperaccumulation of Sr by raspberry leaf mass was noted. The content of this TM in the leaves was 1233.6 ± 360.5 µg^-1 (CBA - 27.8 ± 5.8). The ability of raspberries to actively accumulate Cu, Cr, Sn and Hg is also shown. The CBA value for Hg was a maximum of 58.3±25.5. An analysis of the distribution of HM salts in raspberry shoots showed that their main content is found in the outer layers of the shoot, which is consistent with the bundle type of organization of the conducting raspberry tissue. The distribution of HM salts was uneven along the length of the stem. The main content was noted in the initial sections (0-15 cm), and then decreased in length to trace amounts (Pb, Co, Hg, Cs, Cr, As, and Fe). For Sn, Ni, Cd, and U, a jump of 45-50 cm was noted, which coincided with the location of the plant's leaf mass. The opposite results were obtained with respect to Sr and Zn. Their content increased evenly from the base of the shoot to the top of the stem. For these types of HM, the highest content in the leaf mass is noted.

The relevance of this work is determined by the increasing anthropogenic impact on the environment, including that associated with the spread of natural radionuclides. This work studies the accumulation of radionuclides (U, ²²⁶Ra, ²¹⁰Pb, ²¹⁰Po) and their chemical analogues (Ba, Sr, Pb) in different organs (leaves, branches, wood, bark) of the common rowan (Sorbus aucuparia), growing in an area contaminated more than 60 years ago by radium mining waste, and also assesses the plant’s response to combined radiation and chemical stress. Specific patterns of element accumulation were identified. It was found that 226Ra, Ba, and Sr have the highest accumulation coefficients and are predominantly distributed in the bark and branches. ²¹⁰Pb, ²¹⁰Po, and stable lead have low accumulation coefficients and accumulate mainly in the branches of the rowan. The biophilicity of ²¹⁰Po was higher, as indicated by the ratios of specific activities ²¹⁰Po/²¹⁰Pb > 1 in all organs except wood, where the ²¹⁰Po/²¹⁰Pb ratio was close to unity. Uranium was characterized by the lowest accumulation coefficients. Its content in plants in the contaminated area was comparable to or lower than control values, with the highest radionuclide concentrations observed in bark and leaves. Despite the high level of soil contamination and pollutant accumulation, key biochemical parameters (total antioxidant activity and polyphenol content) remained stable, indicating the relative resistance of rowan to chronic contamination. The obtained data are valuable for the development of bioindication strategies, the remediation of radioactively contaminated areas, and environmental risk assessment.