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The article presents the results of reconstruction of the long-term paleo-fire dynamics in the forest-steppe zone of Western Siberia (Novosibirsk oblast) using the example of the Nikolaevsky ryam peat thickness. According to the radiocarbon dating, the studied peat column has been formed during 3200 cal. yr BP from the Late Subboreal to the present. Twenty-one local fire episodes were identified and time of their occurrence, frequency and intensity were determined based on the macro-charcoal and radiocarbon analysеs. In addition, data on the dynamics of paleo-fires in the forest-steppe ryam were compared with published paleoclimatic reconstructions for the Baraba lowland. At the end of the Subboreal period, six pyrogenic episodes were identified with a peak of fire activity during 2850-2750 cal. yr BP at a rate of accumulation of charcoal particles of 370 particles cm²/year. Most of the fires occurred in the Subatlantic period, namely, 15 fire episodes with the largest local fire activity in the period of 1100-1050 cal. yr BP and the rate of accumulation of charcoal particles reaching 600 particles cm²/year. These paleo-fire peaks coincide with climate warming in the Baraba lowland, marked as an increase in the average July temperature and the predominance of forest-steppe phytocenoses in composition of vegetation cover of the Baraba. Wetter climate conditions and the spread of taiga vegetation from 2100 to 1700 cal. yr BP prevented the occurrence of fires in the territory of the ryam. In addition, during colder climatic periods, fires were either completely absent or of low intensity. When comparing the dynamics of paleo-fires of the Nikolaevsky ryam with paleoclimatic reconstructions, the influence of the climate change on the occurrence and intensity of pyrogenic episodes was revealed.

The purpose of this work was to analyze the state of Scotch pine forests polluted by technogenic emissions from the Irkutsk aluminum smelter (IrkAZ) from the moment it was launched to the present (more than 50 years). The level of the forest pollution was assessed based on the content of inorganic elements in the pine needles. The trees vital state was estimated using the life status index (LSI). A direct dependence of the vital state of pine stands on the dynamics of emissions from the IrkAZ was revealed. Thus, the rapid development of visual signs of needle damage (necrosis and chlorosis), an increase in the level of tree crowns defoliation up to 70 %, the appearance of drying trees in local areas near IrkAZ were observed in the late 1970s and early 1980s (period of maximum emissions, 90-100 thousand tons/year). The fluorine content in the needles reached 210 mg/kg of dry weight. LSI of trees did not exceed 2-3 points, which indicated a strong deterioration in the parameters of pine stands. The area of heavily oppressed tree-stands reached 20 thousand hectares. The level of technogenic emissions from IrkAZ decreased at the end of the 1990s, and the state of pine stands began to improve, LSI of trees increased to 4,9 points. In the last 5 years, the amount of emissions from IrkAZ has remained unchanged (about 35 thousand tons/year), the level of fluorine in the tree needles near the plant is quite stable (70-80 mg/kg of dry weight). LSI of trees has increased to 5,3 points, there are no drying tree-stands. The area of heavily weakened forests does not exceed 2 thousand hectares. Despite the positive dynamics in the change in the state of pine stands, further monitoring of their state is required to predict changes in sustainability of forests in the polluted areas of the region.

This paper presents results of field studies into the soil biota in conditionally undisturbed territories located in the northern part of Cisbaikalia (central ecological zone). This territory is characterized by high landscape diversity, which is due to the peculiarities of the relief and, associated with this, local climatic conditions. Thus in a relatively small area of the territory there are various geosystems from meadow-marsh to mountain-steppe. Soil zoocenoses are accordingly also diverse, and the structure of the population, the average number and biomass make it possible to evaluate communities by taxonomic diversity. This indicator characterizes not only the state of the soil mezopopulation, but also its resistance to external influences. In conditions of limited economic activity, this territory can be a kind of testing ground for comparative analysis and assessment of the restoration potential of soil zoocenoses. Taxonomic diversity was calculated using Margalef’s index, which makes it possible to link two characteristics, the abundance and the number of taxa per unit area. Based on the calculations obtained, five categories of taxonomic diversity of soil invertebrates (from very low to high) were distinguished. Taking into consideration the high landscape diversity of the territory, the spatial distribution of soil mezopopulation reflects the full range of zoocenoses in the region. The numerical characteristics of the mezopopulation of soils are influenced by the hydroclimatic conditions of the territory which, in turn, depend on the terrain. Results from investigating the soil mezofauna aimed at assessing the taxonomic diversity in the spatial aspect are intended to be used as a basis for cartographic modeling in the future.

The article presents the results of temporal and spatial distribution of aerosol particles and micro-admixtures included into them (polycyclic aromatic hydrocarbons, polychlorinated biphenyls) in the near-water layer of the atmosphere above Lake Baikal obtained during a ship expedition from July 18 to July 24, 2022. During the study period, in the lake near-water atmosphere, mainly low values of mass and number concentration of aerosol particles, and resistant organic pollutants (PAHs, PCBs) were observed compared to the fire hazard periods of 2016-2020. During the expedition, the PAHs content in the atmosphere varied from 0,071 to 2,6 ng/m³, which is lower than the concentrations established during the fires (0,22-133 ng/m³). Increased concentrations of the studied components were found only in some areas of Southern Baikal, where the formation of aerosol structure occurred due to local pollution sources situated in the populated near-shore areas (namely, Listvyanka, Kultuk, Slyudyanka, Baikalsk), and at the moment of transfer of polluted air masses northwestward to the lake from Irkutsk and Angarsk. In the aerosols samples from background areas, a PAHs group with two or three benzene rings dominated mainly by naphthalene and phenanthrene. Near local sources in the southern part of Lake Baikal, the proportion of PAHs with four, five and six benzene rings (fluoranthene > pyrene > benz(b)fluoranthene) increased; they are of pyrogenic origin and are formed at high temperature processes of organic fuel combustion (while combusting coal, wood, liquid fuel). We revealed a positive correlation between the content of aerosol particles and PAHs. The revealed concentrations of aerosol particles (1,0-13,7 mg/m³) and benz(а)pyrene (0,01-0,22 ng/m³) rated in Russia did not exceed the MAC. Despite the prohibition of production and limited use of PCBs, their traces were found in various industrial and background regions worldwide. It is shown that polychlorinated biphenyls content in Lake Baikal near-water atmosphere (0,48-5,63 pg/m³) is comparable to the concentrations observed in background regions worldwide (0,04-25 pg/m³).

Methodological approaches to the identification of hydrologically sensitive landscapes have been developed and implemented in the Selenga River basin. The topographic humidity index TWI was calculated to detect accumulative landscapes using the digital relief model of the region under study. Areas with TWI ranges of 12-15 and 15-18 were recognized as areas with the most likely runoff zones. To assess the possibility of their influence on the formation of the river runoff composition, a map of the total runoff was created using the Flow Accumulation model. Hydrologically sensitive watershed areas (HSA) were determined by superimposing a spatial distribution map of areas with maximum total runoff values on the TWI differentiation map. Areas with the contours located within the territories of maximum values of total runoff were identified as true hydrologically sensitive landscapes. Model polygons were selected to test the methodology for mapping hydrologically sensitive areas and primary pollution sources. Studies were carried out on the model territory of the city of Ulan-Ude, which is one of the main pollutants of the waters of the Selenga River and Lake Baikal. The main condition for the formation of secondary sources of pollution (accumulative landscapes) is the correspondence of the pollution source coverage area with HSA. The resulting map of production facilities was superimposed on the HSA spatial distribution map, fragments of which within industrial zones were identified as possible secondary sources of pollution (critical sources areas - CSA). The accuracy of the CSA allocation has been confirmed by the results of assessing the level of soil pollution in the city of Ulan-Ude.

One of the main directions of the modern study of landscape structure is timely updating of the structural and dynamic features of geosystems, taking into account the degree of anthropogenic load. The article examines the historical prerequisites for the development of ideas about the physical and geographical division of Orenburg oblast. A geoinformation analysis of remote sensing data has been carried out using neural network algorithms based on self-organizing Kohonen maps in order to compare the structure of natural boundaries with the actual structure of natural-anthropogenic complexes. For this purpose, we calculated quantitative indicators (namely, the area of the physical-geographical region, the number of classes (types of tracts), the number of landscape contours, the average number of contours in a class, the average area of one contour, the density of contours in the physical-geographical region, the coefficient of complexity, the maximum possible complexity of a landscape, the absolute organization of a landscape (a measure of imbalance), the relative organization of a landscape, and the coefficient of landscape fragmentation) and indices of differentiation of the landscape structure (coefficients of entropic complexity and Shannon diversity, and indices of heterogeneity of Ivashutina-Nikolaev, Odum, Glison-Margalef, and Simpson). Moreover, schematic maps of the region’s territory were compiled, reflecting their spatial distribution over landscape areas. Based on the results of the study, tendencies of changes in the landscape structure of Orenburg oblast have been determined. They include changes in the degree of contouring of geosystems, dynamics of the severity of interlandscape boundaries, anthropogenic dispersion of geosystems, the degree of dominance of individual elements of the landscape. Differences in the tendencies of changes in the landscape structure of forest-steppe, petromorphic and hydromorphic geosystems in comparison with the arid steppe landscapes prevailing in the region have been identified depending on the degree of agrogenic and technogenic transformation.

Fluvial processes play an important role in the transformation of the relief in the Fore-Baikal region. The structure of valley geosystems is one of the important indicators of the dynamic state of fluvial systems. Nevertheless, insufficient attention is paid to the its study in the Fore-Baikal region. The large-scale mapping of the valley geosystems of the Kitoy River in different geodynamic settings was carried out based on the data of complex field works and orthophotography made using UAVs. The features of their spatial structure and dynamics were analyzed. As a result of the study, it has been found that the geomorphologic structure of the territory, which determines the rate of channel deformations and the intensity of slope processes, has a significant impact on the development of valley geosystems and their spatial structure. The section of the Kitoy River valley, which is formed in the flat part of the basin, is characterized by the most complex structure. In the mountainous part of the river basin, there is a fragmented development of individual morphological elements of the valley and lower diversity of elementary geosystems. Based on the results of the analysis of successional changes in the soil-vegetation cover on different morphological elements of the valley, the main stages in the development of the valley geosystems were determined, and the quantitative characteristics of the main indicators of the development stages of floodplain generations and their dynamic state were obtained. For geosystems of the low and middle floodplain of the Kitoy River valley, fluvial processes are the leading factor in the formation of their spatial structure and dynamics, with the exception of the high mountain part of the basin, where they are smoothed out by cryogenesis processes. The series of successional changes in the soil-vegetation cover on these morphological elements are identical almost throughout the entire length of the valley. Geosystems of high floodplains and low terraces, formed under conditions of weakened influence of fluvial processes, have more pronounced features of mountain and piedmont taiga, depending on the change in altitudinal belts.

The article considers ecological and geographical features of officinal plants distribution within the highlands of Northeastern Transbaikalia. The concept of ecosystem diversity was used as a methodological basis of the study. According to it, the orobiome presents a key regional unit for inventory and assessment of mountain biodiversity. Comparative geographic and cartographic methods of analysis of original field data, papers and maps were applied. We have identified 40 species of pharmacopoeial plants for the Northeastern Transbaikalia orobiome. The taxonomic, biomorphological, ecological, geographic, and altitudinal characteristics have been considered, and the analysis of composition of active substances and the use in the treatment of diseases according to the international classification of diseases ICD-10 has been carried out. It has been revealed that the highest number of species are applied when treating diseases of the digestive system, diseases of the circulatory system, and diseases of the respiratory system. Five geographical groups of pharmacopoeial species have been identified, among which species with the Holarctic distributional type prevail. Boreal species predominate among nine ecological-coenotic groups. The coenotic value of pharmacopeial species in vegetation communities of the orobiome is considered. Some species of officinal plants are coenose-formers, predominant in the background communities for the belts; they include Scots pine, Siberian fir, lingonberry, marsh rosemary, downy birch, and bearberry. The regional and altitudinal features of pharmacopeial species distribution have been revealed. The highest number of species grow on the North Baikal highlands, while the smallest number - on the Patom highlands. There occur more than 20 species in the mountain-taiga belt, and about 5-10 species in the high-mountain belt. A map of communities with the participation of typical species of pharmacopeial plants of resource importance has been compiled. It has been revealed that the greatest diversity of these resources is concentrated on the North Baikal highlands due to climatic conditions and geographical location at the junction of biogeographical boundaries. The compiled map can be used to assess the ecosystem potential of the vegetation cover of a poorly explored region. The expediency of further study of the pharmacological properties of local flora species used in traditional medicine, as well as strengthening of measures for the protection of medical plant species, were noted.

The article discusses the results of the complex landscape survey of the Nabil plain, Northern Sakhalin, Russia. The 20 km long landscape profile allocates three major geographical complexes. The main pattern of the landscape structure is related to the age and genesis of the area. The current landscape structure of the Nabil plain includes 31 land units. Within the landscapes, the peculiar features of the soil and vegetation cover are observed, and the main factors of landscape differentiation are the redistribution of runoff associated with the topography and lithological conditions. The spatiotemporal sequence of the land units at the recent marine terraces is related to the coastal sediment accumulation and redeposition. Seven land units are identified here. As a result of mechanical disturbance and deflationary processes in the initial weakly stable complexes of coastal terraces, disturbed land units occupy up to 30 % of the total landscape area. For the coastal plain, 10 land units are identified; up to 90 % of the total landscape area is covered by swamps. Pyrogenic modifications occupy up to 70 % of the total landscape area. The highest landscape diversity is characteristic of the piedmont plain (14 units of the first order). The high conservation value of the dark coniferous forests dominating the landscape is shown. Modified and weakly stable land units (cleared areas and disturbed swamps) occupy up to 1 % of the landscape area. The landscape structure and diversity are represented on a large-scale map; its fragments reflect the main patterns of the landscape distribution and contain information on topography, soils and vegetation. The large-scale map can be used for the environmental monitoring goals, taking into account increasing levels of the man-caused impact at the natural complexes of the northern Sakhalin.

The purpose of the study is to identify the spatial relationship between the population and production of the territories of the south of Yenisei Siberia (Krasnoyarsk Territory without northern areas, the Republic of Tyva and the Republic of Khakassia). The study was conducted using statistical, cartographic and comparative geographic methods; urban districts and municipal areas were chosen as units of statistical observation. The main results include identifying the main urbanized areas and transport corridors in places of maximum population concentration. Thus, the demographic potential of the Krasnoyarsk part of the Trans-Siberian transport corridor makes up more than half of the region’s population, while it receives migrants from peripheral territories. The branches of industrial specialization have been singled out, and a grouping of municipalities of the region has been carried out according to the volume of industrial production (4 groups have been identified). The influence of the level of development and distribution of productive forces on the demographic situation and the transformation of settlement systems has been assessed. The correlation between the population size and the volume of industrial production for the set of urban districts is very high (0,98), and for the set of municipal districts is very weak (0,28), indicating large differences. Сonsideration of cities as nodes of the supporting framework of the region’s territory shows a very strong correlation between population and industrial development, which is obscured when the analysis is extended to the entire territory of municipal districts. The geographical aspects of spatial development are expressed in the strengthening of the central-peripheral gradients of the concentration of population and production. Modern market conditions through the strengthening of economic contrasts, the weakness of subsidized budgets, and the degradation of local infrastructure affect the demographic situation. In all the regions considered, the dominance of capital cities in terms of demographic and industrial potential has been noted; it is these administrative centers that are regional points of growth. The grouping of municipalities by production volume shows the unevenness of industrial development. The leaders and nodes of the supporting framework of the territory are cities with developed industries of great all-Russian, regional or export significance as well as centers with extractive industries.