Home – Home – Jornals – Geography and Natural Resources 2022 number 4

The post-Cenomanian sedimentary sequence of the East Messo-Yakha oil and gas field in the southern Gydan Peninsula comprises twelve lithological units (beds) correlated to Upper Cretaceous, Paleogene, and Quaternary regional stratigraphic stages and formations. The facies of the sedimentary units are constrained from lithology and microfossils. The stratigraphic division is based on bio-stratigraphy (fauna and spore-pollen assemblages), paleomagnetism, and geochronology (quartz and feldspar grains dated by optically stimulated luminescence). The deposition record is interrupted by six large stratigraphic unconformities. The obtained data provide new insights into the Late Cretaceous, Paleogene, and Quaternary paleogeography of the area.

In August 2019, four descending (gravity) springs in the Inya River valley were sampled during the field works conducted within the study of low-radon waters of the Novosibirsk urban agglomeration in the area lying away from known granite massifs. Laboratory analyses have revealed enhanced radon activity concentrations (from 5 to 149 Bq/dm³). It has been established that these waters are fresh, of HCO₃ Mg-Ca chemical composition, and have a TDS value of 413 to 548 mg/dm³ and a silicon content of 4.1-8.6 mg/dm³. They are characterized by neutral to slightly alkaline pH (7.1-8.4) and oxidizing geochemical conditions with Eh from +205.3 to +231.8 mV and O_{2 dissolv.} = 6.24-12.26 mg/dm³. The revealed predominance of SO₄^2- over Cl^- concentrations in the waters of the study area was probably due to the presence of sulfides in the water-bearing sediments, in particular, pyrite in the surface sediments. More than tenfold proportional excess of Ca concentrations over Si in the Inskie spring waters indicates the predominantly carbonate composition of the water-bearing sediments. The gross α-activity of waters is 3-4 mBq/dm³, and gross β-activity is 11-15 mBq/dm³. Natural radionuclides are found in the spring waters within the following limits (mg/dm³): ²³⁸U, from 2.83 · 10^-3 to 4.13 · 10^-3; ²³²Th, from 2.39 · 10^-6 to 1.16 · 10^-5, and ²²⁶Ra, from 3.83 · 10^-10 to 4.93 · 10^-10. The value of the ²³²Th/²³⁸U ratio for the waters ranges from 5.79 · 10^-4 to 3.61 · 10^-3, as a result of the oxidative geochemical migration-arresting capability of thorium. The uranium isotope ratio (γ) ²³⁴U/²³⁸U varies from 2.6 to 3.2 for the waters, with the uranium isotope activity determined as 117-124 mBq/dm³ for ²³⁴U and 38-48 mBq/dm³ for ²³⁸U. This indicates shallow circulation of the studied waters as compared with those of the Svyatoi spring in Verkh-Tula Village, for which γ = 1.3; the ²³⁴U activity, 147 mBq/dm³; and the ²³⁸U activity, 115 mBq/dm³. By isotopic composition, the origin of the spring waters is assigned to the infiltration type, and they are characterized by relatively narrow distribution of δ¹⁸O (from -17.5 to -16.7‰) and δD (from -128.4 to -126.2‰) values. The δ¹³C_DIC values are from -10.3 and -10.9‰ in springs 3 and 2 and become lighter (-11.2 and -12.1‰) in springs 1 and 4, respectively. This is due to significant participation of surface waters in the recharge mechanism of springs 1 and 4, which is also consistent with the δ¹⁸O and δD data and ¹⁴C dating. The estimated age of water-dissolved carbon is 1478 ± 81 years for the waters of spring 3 (the oldest), while it is found to be only 651 ± 53 years for spring 4 and is estimated as modern for spring 1. The reported decline in the age of water-dissolved carbon down to recent age is indicative of increased contribution of surface water to the spring recharge area. The C and O isotope compositions of calcite of the host aquifer rocks are characterized by close values for most of the samples: δ¹³С varies within narrow limits (from -3.1 to -2.7‰), and δ¹⁸О varies from 17.2 to 18.4‰. The isotopic composition becoming lighter for carbon (up to -11.0‰) and oxygen (up to 13.9‰) was noted for weathered schist samples. Results of the carbon isotope analysis of rock samples, their organic component, and water indicate an active isotopic exchange in the water-rock-organic matter system.

The current stress state of the Earth’s crust on the territory of Uzbekistan is studied using algorithms from the cataclastic analysis of displacements (CAD) with the application of a combined catalog of earthquake source mechanisms. The axis of maximum compression is nearly horizontal and orthogonal to the strike of tectonic structures for the larger part of the area under study, and the angle of penetration of the axis of minimum compression varies greatly for different parts of the territory. The areal distribution of the Lode-Nadai coefficient indicates the predominance of a stress state close to pure shift for the area under study. Without differentiation of the seismically active bed by depth, almost the entire territory of Uzbekistan is characterized by a geodynamic stress state corresponding to horizontal compression. There are significant differences in the stress state parameters for different deep beds of the Earth’s crust. With account for the representative recording periods of seismic events of different energy levels, the earthquake recurrence parameters for the entire territory as a whole and large seismically active zones are determined. It has been established that the epicenters of strong earthquakes recorded since the historical time are grouped in compact areas with linear dimensions of 50-80 km. The tectonophysical interpretation of the selected areas is given within the framework of the CAD, in which it is noted that strong earthquakes occur mainly in areas of lower effective confining pressure and maximum tangent stresses. This is due to the fact that the values of friction forces at faults in such areas are low, which creates the most favorable conditions for large-scale destruction. According to the results of the reconstruction of the natural stresses of the CAD, such areas on the territory of Uzbekistan are identified within faults and flexural-fault zones in South Fergana and North Fergana, as well as in the Gazli region. The current seismological situation in the selected areas of long-term forecast is estimated using a set of prognostic parameters of the seismic regime, and a map of the areas of expected seismic activity is compiled. The analysis of previous forecast maps developed within the framework of the presented approach shows high value in their information.

This paper presents the results of 3D inversion of magnetovariational tippers obtained at the Cape Schmidt observatory via digital processing of geomagnetic variation records performed by the MAGDAS-I magnetometer. 3D tipper frequency inversion is carried out using the ModEM software. The result is horizontal and vertical sections in the coastal strip of the Chukchi Sea in a spatial region with a dimension of 300 × 300 × 200 km along the X , Y , and Z axes, respectively. The geoelectric section of the investigated region contains both surface and deep conductive blocks located at different azimuths relative to a measurement point. The surface conductive anomaly near the observatory with a resistivity of ≈3 Ohm·m is located in the southeast direction at depths of a few hundred meters. The other conducting inhomogeneity is larger and located in the same direction, but at a distance of about 25-30 km and depths of 4-16 km. The resistivity of its central region at a depth of 8 km is equal to 1 Ohm·m. From the side of the South Chukchi Depression, there is an inclined conductive block in the Chukchi Sea, located closer to the coast to the bottom of the Earth’s crust, and the maximum resistivity of this block in the central part at a depth of 20 km is equal to ≈7 Ohm·m. The most noticeable feature of the section is a massive upper-mantle conductive block under the continent at depths of 50-120 km with a resistivity of 3-4 Ohm·m in the central part at depths of 70-85 km. Deeper into the continent, the block is slightly inclined to the southeast. There are visible conductive regions that connect this block with upstream conductive formations. The epicenters of weak crustal earthquakes recorded in the region are located above the northwestern marginal part of the upper-mantle block, including its central region. Possible mechanisms of high electrical conductivity of anomalous blocks are discussed.

The results of high-sensitivity recording of the Wulf group absorption bands of the ozone molecule in the range 9350-10000 cm^-1, which corresponds to transitions from the ground to an excited triplet electronic state, are discussed. The spectrum in this range above the main molecular dissociation threshold was recorded for the first time with the use of a cw-CRDS spectrometer with sensitivity of 1 × 10^-10 cm^-1 in terms of the absorption coefficient. The measurement technique and the procedure of ozone generation and its concentration monitoring are described. A comparison with the previously calculated theoretical spectra of the ³A₂(000) ← X¹A₁(000), ³A₂(010) ← X¹A₁(000) and ³A₂(010) ← X¹A₁(010) singlet-triplet bands is carried out.

Based on known expressions applied to diffraction-limited optical systems, estimates are given and a method is proposed for determining the measurement error of the longitudinal coordinates of particles from images reconstructed from digital holograms. A correction factor for visual focusing is determined for different distances between a detected particle and the plane of a CMOS matrix. The experimental results of testing the method are presented. It is shown that the error of automatic digital focusing can be reduced by simultaneously applying focusing curves for several quality indicators and optimizing the image area for their construction.

The long-term measurements of the aureole scattering phase function are analyzed for angles φ = 1.2° and 20° ( I_1.2 and I₂₀), which were obtained using a closed-type halo photometer at the aerosol station of the LAO of the IAO SB RAS in 2010-2021. The analysis of the temporal variability of the parameters was carried out for interannual and annual data and the diurnal behavior of hourly measurements. The daily averages were calculated from the hourly averages, the monthly averages, from daily averages and the annual averages, from the monthly averages. A weak but significant ( p = 0.05 level) time trend was found only for the interannual values of I_1.2, which amounted to 1.14% per year. In the annual course of I_1.2, a monotonous increase in the values from winter to summer months is clearly observed. In the annual course of I₂₀, we see a decrease in values from winter to summer. Smokes from distant wildfires in 2012 and 2016 and partially in 2018 and 2019 disrupt this pattern with increased I₂₀ values in July and insignificantly in June, August, and September. The diurnal behavior of the aureole scattering phase function values I_1.2 and I₂₀ and the ratios I₂₀ / I_1.2 constructed for the annual variation of monthly average daily values are typical of the behavior of surface aerosol under continental conditions. Smokes from remote wildfires lead to high values of I₂₀ at night, morning, and evening, and the decrease in I₂₀ during the daytime is insignificant with a probability of 0.95 due to the high standard deviation.

The paper considers the propagation of high-power femtosecond laser radiation through aerosol. The propagation of high-power femtosecond laser radiation is simulated with flat phase screens that simulate the passage of radiation through an aerosol layer, which has effective optical parameters corresponding to different intensities during nonlinear interaction. In the course of experimental studies, the effect of aerosol on the position and length of the filamentation domain and the number of filaments was shown. With a decrease in the concentration of aerosol particles in the air in front of the filamentation domain, the filamentation domain approaches and its length increases to the same size as without aerosol, and the number of filaments also increases.

In with paper we demonstrate the application of original method for solving the inverse problem of hyperspectral satellite sensing to retrieval of the vertical profile of HDO/H₂O ratio in the Earth's atmosphere with the simultaneous use of thermal and near-IR spectra is described. This method is used to retrieve relative abundance of HDO isotopologue (δD) in atmospheric water vapor from measurements of TANSO-FTS IR spectrometer onboard GOSAT-2 satellite for the first time. Retrieved δD-values are compared with data obtained at ground-based TCCON measurement station in Karlsruhe, Germany. The simultaneous use of satellite spectra of outgoing atmospheric radiation in the thermal range and reflected solar radiation in the near-IR shows a higher correlation between monthly average δD satellite values of and ground-based data.

The ranges of changes in the parameters of wind and temperature (refractive) turbulence estimated from lidar data, corresponding to the intensity of aircraft shaking severity caused by turbulence in the free atmosphere at flight altitudes, are determined. It is shown that both the estimation of the variance of the radial velocity measured by a coherent lidar in the direction of flight, and the determination of the structural constant of the refractive index from the data of the lidar, which measures the intensity of refractive turbulence in flight direction, make it possible to judge the potential danger of aircraft shaking severity in clear air turbulence zones ahead of the aircraft.

The paper presents the results of analysis of radar characteristics of clouds, including the polarization ones, and lightning data for June 9 2020, in the vicinity of Saint-Petersburg. The characteristics of thunderstorm and clouds without lightning are compared. Statistical difference between two groups of clouds has been found. The regression analysis of the correlation between the lightning flash rate and radar characteristics of clouds is performed using neural networks. The impact of these parameters on lightning flash rate has been estimated. A mathematical equation for calculating the lightning flash rate using the differential reflectivity maximum and the cloud volume with the reflectivity equal to 35 dBZ is derived.

The paper analyzes the time and space derivatives of the wind vector components and the derivatives in the case of resolution into deterministic, meso-gamma-scale, and turbulent parts. Experimental data on the wind vector components obtained in the surface air layer with ultrasonic thermoanemometers were used for the analysis. The main task was to estimate the values and the variability ranges of the derivatives including meso-gamma-scale variations in the wind field. The aim of the study was to compare the variability ranges of these derivatives with those of the “classical” derivatives (when only deterministic and turbulent parts of the wind vector are considered). It is shown that meso-gamma-scale variations in the wind vector components can be no less important than the turbulent parts included in the “classical” schemes used for simulation (prediction) of the wind field with high space and time resolution.

The work is devoted to the study of the dynamics of greenhouse gas flows, which were measured from 2017 to 2021 at the Background Observatory of Institute of Atmospheric Optics SB RAS. It is shown that the annual average SO₂ flows at the observatory varied from -283 mg × m^-2 × h^-1 (runoff) to +31 mg × m^-2 × h^-1 (emission). The minimum emission of 1351 mg × m^-2 × h^-1 was recorded in 2019 and the maximum emission of 1789 mg × m^-2 × h^-1 in 2021. The lowest runoff was observed in 2017 (2099 mg × m^-2 × h^-1). The largest, equal to 2304 mg × m^-2 × h^-1, was in 2018. The annual average methane fluxes ranged from -0.032 mg × m^-2 × h^-1 in 2018 to -0.047 mg × m^-2 × h^-1 in 2020. The maximum methane emission was recorded in 2018 and was equal to 0.915 mg × m^-2 × h^-1, and the minimum in 2021 was only 0.095 mg × m^-2 × h^-1. At the same time, the maximum runoff in the interannual variability varied in a narrower range from -0.241 to -0.361 mg × m^-2 × h^-1. Unlike SO₂ and SN₄, the soil of the measurement area turned out to be a weak source of N₂O. The annual average fluxes of this gas were in the range 0.00-0.011 mg × m^-2 × h^-1. Internal maximum emissions from 0.237 to 0.301 mg × m^-2 × h^-1 and runoffs from -0.206 to -0.245 mg × m^-2 × h^-1 also changed little.

The impact of the water vapor continuum absorption in the atmosphere on CO₂ radiative forcing is estimated on the basis of mass calculations of thermal radiative fluxes for summer conditions in 2021 in the Lower Volga Region. The set of 368 vertical atmospheric profiles (four realizations per day during three summer months) was used for the simulation. It was shown that the humidity growth decreases the CO₂ contribution to radiative impact on the Earth’s surface, which leads to weaker heating of the surface and stronger heating of the atmosphere. Thus, greenhouse effect reinforcement due to the CO₂ concentration increase at high humidity will lead to greater heating of the atmosphere. The water vapor continuum plays a dominating role in this process, but not selective absorption in H₂O bands.

The spatial and temporal variability of forest floor moisture characteristics is analyzed on the basis of the Canadian Fire Forest Weather Indices (CFFWIS) for the territory of Western Siberia (45-75° N, 60-90° E) over 2016-2021 for the first time. The floor moisture effect on the number of wildfires (hotspots) during the warm season (March-October) is assessed. The results are given for different natural zones. Statistically significant correlations are found between hotspots and floor moisture at a depth of 7 cm only in some spring and summer months (correlation coefficient is up to 0.54). The strongest effect (correlation coefficient is up to 0.60) on wildfires is observed for floor moisture at a depth of 1.2 cm in the south of Western Siberia in April. Thus, it can be concluded that the forest floor moisture is an important parameter in description of conditions for fire initiation and development. However, the question about its effect on the wildfire behavior remains open and requires additional research accounting meteorological and atmospheric conditions. The results can be used in future for solving problems of forecasting the potential fire danger.

The impact of aerosol sources on the atmosphere pollution of Russian Arctic sector is underestimated. The newly aerosol station was installed on Bely island (Kara sea) in August 2019, it is located on the way of air mass transportation from industrial regions of Western Siberia to the Arctic. Continuous aethalometric measurements of short leaving climate tracer - black carbon are carried out. They showed the seasonal variability with high values from December to April (60 ± 92 ng/m³) and low in June-September (18 ± 72 ng/m³). Pollution events with concentration higher background are identified. Regional distribution of fossil fuel and biomass burning sources are obtained by the concentration weight trajectory model. Impact of gas flaring from oil and gas extraction areas of Western Siberia, Volga-Ural, and Komi Republic is the most pronounced during the cold period while the wildfire smoke emissions are dominated in warm season. The difference between the black carbon concentrations in ultraviolet and infrared wavelength regions serves as a marker of biomass burning impact on the aerosol composition, indicating the residential wood combustion and agriculture and wildfires during cold and warm season, correspondently.

A technique has been developed and a calculation has been made of the irradiance of the entrance pupil of a ground-based optoelectronic system (OES) from a cylindrical space object illuminated by the Sun at night. The results of calculating the minimum irradiance and corresponding stellar magnitude at the input pupil of the OES are presented with a signal-to-noise ratio at the output of the photodetector matrix with a current equal to 7 in the wavelength range of 0.45 ÷ 0.85 mm. The dependence of the signal-to-noise ratio on the distance to the space object for its three different sizes is constructed. The program ROSN-1 was developed and its control panel was presented for calculating the characteristics of ÷ 0.85 mm was presented, and the possibilities of this program were explained.

The features of high-power and high-contrast imaging in a bistatic laser active optics system (laser monitor) are considered. In the developed system, a brightness amplifier has a larger volume than an illumination source, which makes provides for high-power contrast images of micro objects. For the first time, the influence of the time shift between a superradiance pulse of the amplifier and the time of signal arrival at its input on the contrast and power of images formed by one pulse was was ascertained. It is shown that artifacts formed as a result of the superluminous radiation "parasitic" reflection and scattering from optical circuit elements significantly reduce the contrast and power of the generated signals. This effect can be eliminated by the generation of an amplifier input signal before the generation of amplified spontaneous emission. The optimal delay is 1 ns.

In accordance with regulatory documents, the organization and conduct of logging operations should be carried out by methods and techniques that ensure maximum conservation of forest environment, contribute to the reproduction of valuable forests in the shortest possible time, and strentength their protective and protective functions. This is especially true for the coniferous-broad-leaved forests of the Far East, which are a unique formation that includes cedar and black-fir-broad-leaved, spruce-broad-leaved, hard and soft-leaved subformations. These forests are characterized by a very complex canopy structure. The composition includes, as a rule, 10-20 tree species, differing in their biology and growth, which creates a clearly expressed vertical density of the forest stand. The presence in plantations of endemic and forbidden species, as well as lianas and shrubs listed in the Red Book (2008) require a special approach to the methods and technologies of wood harvesting. Studies have shown that in the formation of coniferous-broad-leaved forests, selective felling methods and logging technologies should be predominantly used, allowing not only to preserve undergrowth and fine-grained valuable species, but also to ensure the formation of a post-cutting stands close to the original forest type. This leads to very important conclusions on the organization of wood harvesting only by certain types of machines and mechanisms using narrow stripe technology, which is confirmed by our research.

The total area of protective forests in Amur Oblast in 2022 was 2.51 million ha, of which 1.72 million ha (68.5 %) was forested, 0.18 million ha (7.2 %) was unforested land, and 0.61 million ha (24.3 %) was non-forest land. The share of protective forests in the forest fund of Amur Oblast is 5.6 % for forested lands and 8.2 % for all lands. For most of the post-Soviet period, the area of protective forests in Amur Oblast was characterized by a constant area: in the period 1998-2022, the total area of protective forests was in the range of 2.50-2.52 million ha. According to the contribution, the forbidden strips of forests located along water bodies are the most represented (47.9 % of the forested lands and 49.6 % of all protective forest lands). Spawning belts of forests are in second place in terms of representation (29.0 % of forested lands, 27.2 % of all lands). The third place in terms of contribution is occupied by protective forest belts located along public railways, federal public roads, public roads owned by the constituent entities of the Russian Federation (20.7 % of forested lands, 20.9 % of all lands). The prevailing categories of protective forests quite logically correspond to the economic specifics of the regions of Amur Oblast. The water protection services of the protective forests of Amur Oblast need to be strengthened. Under the conditions of climate warming, it is recommended that the regulatory recognition of forest services to prevent the degradation of permafrost is recommended.

For the first time a study of microbial communities of permafrost forest soils of the Yakut Botanical Garden of the Institute of Biological Problems of Cryolithozone, Russian Academy of Sciences, Siberian branch was conducted. The studied area is characterized by high soil diversity, almost all types of forest soils found in Central Yakutia are common here. It was found that in the studied permafrost soils in 2019, the number of cultivated microorganisms ranged from 5.2 ± 0.5 × 10² to 2.5 ± 0.1 × 10⁶ CFU/g of soil. Humus-carbonate soil turned out to be the most saturated with microorganisms of all types of permafrost soils, and malt was the poorest. According to the total number of microorganisms, humus-carbonate and pale gray soils formed as a result of the turf soil formation process were distinguished. It was noted that microorganisms were concentrated in the upper organogenic horizons and their number decreased with depth. Mycelial microorganisms dominated in the microbocenoses of the studied four out of five types of soils formed on loose light alluvial deposits, and ammonifying bacteria prevailed in the microbocenoses of malt developing on loess-like alluvial loams. It was found that the predominance of certain groups of microorganisms depended on the chemical composition of soils, as well as on the characteristics of their formation. Mycelial fungi were mainly represented by representatives of the genera Aspergillus sp . and Penicillium sp . Aerobic cellulolytic microorganisms were found in the amount of 5.2 ± 0.5 × 10² - 8.3 ± 4.1 × 10⁴ CFU/g, most of them were found in humus-carbonate soil. Nitrogen fixators were found only in humus-carbonate soil (98 %). It has been studied that the number of microorganisms with physicochemical parameters (C, N, pH, humidity) correlates in different types of soils in different ways. The change in the number of microorganisms mainly depended on the soil temperature, humus and nitrogen content.

The article notes the main sources of phytodetritus in undisturbed cryolithic larch forests of Central Evenkia. The features of the distribution of phytodetritus stocks and its individual components depending on the age of forest stands (young, mature and overmature) and forest types are considered. All these stands were formed on the territory of a small drainage basin in Central Evenkia after intensive ground fires in the early and last decades of the 20^th century. An uneven distribution of litter stocks was revealed both in age groups and forest types. Significant annual fluctuations in litter stocks over 7-year observation period were also noted. The composition of the litter is dominated by needles - 84.8-93.2% of the total mass, while the branches and bark of larch ( Larix Mill.) and birch ( Betula L.) leaves account for only 3.0-3.2, 4.5-2.6, and 7.7-< 1 %, respectively. It was established that according to the degree of accumulation of phytodetritus in the main types of larch forests of the basin under consideration, they are arranged in the following descending order: ledum green moss, red berry green moss, shrub green moss. Litter stocks in them vary from 2.4 to 76.3 t/ha. The total stock of litter in the territory of the basin is 133038 tons, of which 103916 tons fall on larch forests, with a predominance of mature and overmature - 4966 and 61188 tons, respectively. In larch forests of the permafrost zone, phytodetritus is formed mainly due to the litter of the moss-lichen cover. The role of litter from aboveground organs and root mortmass is insignificant. In all cases, with an increase in the age of forest stands, an increase in the mass of the litter is observed. The role of individual components of phytodetritus in the deposition of biogenic elements was revealed, with a significant predominance of carbon and nitrogen in them and an insignificant content of phosphorus and potassium as additional sources of mineral nutrition in forest biogeocenoses of the permafrost zone, and a low rate of their entry into the soil in the process of detritus mineralization was noted.

The species diversity and state of the ground cover of light coniferous forests in the territories of Irkutsk Oblast, polluted by emissions from three aluminum smelters (Bratsk (BrAZ), Irkutsk (IrkAZ) and Tayshet (TAZ)), differing in production technology and duration of impact on forests, were studied. 188 species of vascular plants from 49 families, 102 species of lichens, including 26 species of epigeal and 13 species of ground mosses were identified. Most species belong to the forest floral complex, mainly to the light coniferous zone-zonal group. Perennial herbaceous plants dominate in the biomorphological spectrum: its basis consist of long-rooted (30 % of the total flora), short-(26 %), and rod-rooted (13 %) species. The mesophytic species dominate in ecological spectrum. The most significant transformation of the species composition was observed in forest communities located in the industrial zone (within a radius of 0.5 km) of BrAZ, where the critical level of contamination of Scotch pine ( Pinus sylvestris L.) trees was found, the drying of trees and the degradation of the grass-shrub layer contributed to the formation of solid moss cushion from silvergreen bryum moss ( Bryum argenteum Hedw.) on the soil. In the industrial zone of TAZ and IrkAZ, where average and strong level of tree-stands contamination, respectively, was found we observed the increase of plant projective coverage to 70-85 % and the total number of vascular plant species due to the appearance of meadow, forest-steppe and ruderal, the composition of phytocenoses often changes towards the predominance of photophilic species. With a low level of contamination of tree-stands, changes in the floral complex are less pronounced and statistically insignificant compared to background territories.

Under conditions of a changing climate, the relevance of assessing the full carbon pool of all components of forest ecosystems increases, not only of the living aboveground and underground parts, but also of litter, large detritus, soils, etc. There are numerous estimates of the phytomass of the aboveground part of forest trees and stands, both taking into account the mass of branches that have died and preserved on tree stems, and without taking them into account. There is no information about the mass of dead branches on tree stems in the available databases on the phytomass of trees. Thus, the mass of dead branches of trees and stands is not included in the calculation of both the input and output components of the carbon cycle, and when estimating the carbon pool of forest ecosystems, it is underestimated by some unknown amount. In the published data on the phytomass of trees, the relative mass of dead branches, i.e. the ratio of the mass of dead branches to the aboveground phytomass, varies from 0.1 to 26 %, however, attempts to identify factors explaining such a wide range of it are quite rare. In this study, the first attempt was made to develop allometric models designed to estimate the mass of dead branches of growing trees of Scots pine ( Pinus sylvestris L.) and silver birch ( Betula pendula Roth) in the conditions of the steppe zone. The study was based on 465 model trees obtained on 35 sample plots. It was found that in the mature birch stand, the mass of dead branches is 1.32 t/ha and relative mass of dead branches is 2.5 %, in natural pine forests 0.9-17 t/ha and 0.7-13 %, respectively, and in plantations 0.2-13 t/ha and 1.3-11 %, respectively. The dependencies constructed for the relative mass of dead branches are combined with yield tables of the aboveground phytomass of stands of natural origin and plantations of the Turgay Depression. It was found that, depending on the origin of the stand, its age and site index, the relative mass of dead branches varies from 0.8 to 15 %. The proposed allometric models and inventory tables can be used in the assessment of the mass of dead branches on tree stems of pine stands. When calculating carbon pools in the forests of the steppe zone, it is necessary to take into account the mass of dead branches by applying increasing coefficients in pine forests from 0.8 to 15% and in mature birch forests 2.5 %.

The article presents for the first time data on the composition and structure of algae groupings in gray forest soils of the town of Usolʼe-Sibirskoe and its surrounding territories, exposed to technogenic pollution. Samples from 19 locations, mainly forest stands, located on the territory of the town (12 locations) and its surroundings (7 locations) were studied. Using culture-dependent methods, 77 species from five divisions of Cyanoprokaryota (22 % of the total number of species), Bacillariophyta (5 %), Ochrophyta (9 %), green algae (Chlorophyta) (61 %), Charophyta (3 %) were registered. The largest number of species are represented by green algae, which is typical for forest soils. A variety of Cyanoprokaryota species was noted in the soils of the town, which are characterized by lower acidity, increased content of exchangeable calcium, sodium, sulfur, and a lower content of total nitrogen compared to the background. In the studied forest stands on the territory of the town, the diversity of algae groupings was higher (the average number of species was 11.7) than in its surroundings (an average of 9.9 species). Composition and structure of algogroups of the studied forest soils of Usolʼe-Sibirskoe testifies to their preservation of common features characteristic of such soils of natural biogeocenoses. According to the number of species, the distribution of species in the departments, the soil algocomplex of forest stands in the town of Usolʼe-Sibirskoe and its surrounding territories is similar to those of other industrial centers of Irkutsk Oblast: Sayansk, Shelekhov, and Irkutsk.

The methodology for valuating regeneration and compensation cost and calculating the amount of damage in case of logging, damage, destruction of green stands, developed for agricultural and municipal lands in the territory of Beysky district of the Republic of Khakassia, is discussed. The replacement cost of green stands is determined per one tree / one bush and is determined by the formula S_v = C_sp × Kd_1.3. The transition from replacement cost to compensation cost is due to the need to take into account in the price of each tree or shrub being valued various aspects of their value. The compensation cost is calculated by applying correction factors to the replacement cost, such factors as their location, actual condition, environmental and social significance, and is determined by the formula S_kd = S_v × K_t × K_s × K_sez× N_d, where S_kd. In cases where green spaces simultaneously belong to different categories allocated to take into account their social and environmental significance, the maximum value of a similar coefficient is taken into account in cost calculations. The amount of damage caused by illegal logging and (or) destruction of green spaces is calculated at the amount of the compensation cost using the multiplying coefficient K_п = 5. cost of damaged green stand. Payment of the compensation cost of cut down green stands in case of forced demolition and damage in case of illegal logging, damage, destruction of green stands shall be credited to the budget of the municipal formation of Beysky district of the Republic of Khakassia.

The article for the first time deals with the issues of natural regeneration of the forest in blown sands - a kind of deserts of the northern taiga and forest-tundra of Western Siberia, which arose on the site of automorphic pine stands, destroyed by natural and technogenic impacts. During the reconnaissance survey of several blows, it was found, that the main factor hindering the natural regeneration of forests in these peculiar deserts of the North is the wind. In this regard, forest formation on them is carried out only in areas adjacent to the leeward side of the forest walls and in low places, as well as in voids between large-sized logging residues covered with sand.

The results of microscopic analysis of 118 samples of solid precipitation (snow) collected during the cold season of 2019-2020 at three key points in the neighboring Altai-Sayan and Tobol-Irtysh glaciological regions and on their border are presented. In 45 samples (38 %), advective pollen grains of trees (Betula sp., Pinus sp.) and herbs (Artemisia sp., families Asteraceae, Amranthaceae s.l. (incl. Chenopodiaceae), Fabaceae, Poaceae) were identified. Territories from which pollen grains arrived with air masses causing precipitation during the cold season were determined. Advective pollen of wormwood (Artemisia sp.) was brought from the territory of the Kazakh Upland and was determined in the snow of both glaciological regions and on their border. Pollen grains of Amaranthaceae s.l. (incl. Chenopodiaceae) were introduced from the plains of Kazakhstan and, partially, from the snow-free slopes of the Altai Mountains and from the Middle Ob Lowland. Pollen of Fabaceae family was only identified in the precipitation of the Altai-Sayan glaciological region, while pollen grains of Poaceae family were found in the precipitation of the Tobol-Irtysh region; in the border zone of the two glaciological regions, pollen grains of these taxa were not found.

Under natural conditions, soils of the active layer are open systems of varying composition, structure, and properties. However, in engineering projects, the values of thermal properties measured in laboratory on isolated samples of constant composition are used to describe their thermal state. To take into account the variability of the thermal properties of active layer soils under the influence of external factors, we propose a method for assessing the equivalent indicators of their volumetric heat capacity and thermal conductivity using a combined analysis of dynamics of soil temperature and heat fluxes based on long-term monitoring data. Monitoring of the heat flux and soil temperature has been carried out at two sites, one of which characterizing the area of seasonally freezing soils, and the other - the area of seasonally thawing permafrost-affected soils. A procedure for processing monitoring data is proposed, which makes it possible to determine the time-averaged effective values of the equivalent heat capacity and thermal conductivity. The proposed technique allows one to trace fluctuations of the equivalent heat capacity and thermal conductivity in time series against the background of changes in external factors of heat transfer in the active layer under natural conditions.

The construction of heated buildings in the Arctic is considered. To increase the bearing capacity of the foundations via their preservation in the frozen state, an environmentally friendly heat-insulating material obtained from the Arctic raw materials (opal-cristobalite and zeolite rocks) has been proposed. The aim of this work is to evaluate the efficiency of insulation layer made of granular foam-glass ceramic on the basis of numerical modeling of the thermal interaction between the heated building and the frozen base. We have investigated the influence of protective screens, construction parameters of a dome-shaped building, and the thickness of insulation layer on the thermal regime of a frozen base over 30 years in comparison with the option without the use of special engineering measures. Calculations indicate that the safe exploitation of a heated building without traditional seasonal cooling devices and a ventilated underground is only possible with the use of protective screens. The building can have the shape of not only a dome but also an elongated ellipsoid of unlimited length. In this case, for building width of 6-8 m, the thickness of insulation layer should be 1.0-1.4 m. The proposed technology is promising to reduce the cost of low-rise Arctic construction, rational use of mineral resources, and preservation of the permafrost and Arctic landscapes.

Glaciation of the northern Baikal region is associated with mountain ranges surrounding Lake Baikal. The underlying rocks are in the frozen state. The existing glaciers are remnants of a larger Pleistocene glaciation, and their area is subjected to continuous shrinking. The analysis of tree cores allowed us to reconstruct the climatic background of the glaciation changes in the recent past. A dendroclimatic curve is divided into two parts: the first part lasted until about 1860-1865, when the summer air temperature was almost always below the mean summer temperature for the entire considered period (~16 °С); the second part (until now) is characterized by higher (above-average) temperatures. During the field work, the current state of the regional glaciation was described for the areas of the Baikal, Barguzin, and Verkhneangarsk ranges. The areas of glaciation were determined from the Landsat 7 and Sentinel-2 satellite images for 2000 and 2021 and were controlled by orthophotoplans based on the UAV survey in August 2021. The maximum reduction of glaciated area over 21 years is generally typical for small forms of glaciation and reaches 10-30 % for the main glaciers. Data on temperature regime of air and rock surface along an altitudinal profile in the Verkhneangarsk Range were obtained for the first time.

This paper presents a retrospective analysis of the geometric electromagnetic induction (EMI) sounding data. The data were acquired in the 1990s in the city of Neryungri to determine probabilistic relationships between unconfined compressive strength of saturated sandstone samples and the attenuation coefficient of the harmonic field induced by a high-frequency vertical magnetic dipole at 1.125 MHz in frozen sandstone rock mass. The results indicate that the consistent increase in the attenuation coefficient with decreasing strength of sandstone rock mass is correctly described by a logistic function equation. The inverse regression relationship is adequately described by a power function equation which can be used as a probabilistic model for predicting mean values of unconfined compressive strength of saturated sandstone rock mass (but not only sandstone rock samples) from the attenuation coefficient. The relative error of model predictions at the 70-80 % confidence level is ±(27.7-32) %, which is close to the limit of allowable error (±20.0 %) for laboratory measurements of mean strength of rock samples. This provides favorable conditions for applying the geometric EMI method in rock strength mapping for geotechnical engineering in Neryungri, as well as in areas of similar geology in southern Yakutia with sporadic permafrost.

A recently published book by L.N. Khrustalev, a leading specialist in engineering geocryology, professor of the Department of Geocryology, Faculty of Geology, Lomonosov Moscow State University is devoted to methods for solving a wide range of problems of engineering geocryology: thermal and mechanical interaction of engineering constructions with bearing rocks, land reclamation measures, methods for assessing the reliability of design solutions for construction in the permafrost zone, as well as methods of predictive calculations for monitoring of objects built on permafrost. This monograph contains a wide range of recommendatory and standard calculations, as well as some previously unpublished author’s works. In essence, it is a desk reference for specialists involved in the design and calculations of engineering constructions on permafrost. Another highlight of the book is its electronic component: all the calculations proposed in the book are implemented in Microsoft Excel macros and are available for download and processing. This practically eliminates the possibility of errors (the user only needs to enter the correct input data).

This article is devoted to generalizing the world experience of geographical expertise of regional digital development strategies to determine the advantages and disadvantages of emerging approaches. It is established that publications on the geographical expertise in national and supranational strategic documents related to the digital development of regions appeared only in the last decade and have not yet received any theoretical generalization in world science. The selection of publications on the subject under consideration was carried out by using the author’s semantic search algorithm based on the ideas of machine learning. Approximately two dozen journal articles were found in eight bibliographic databases. A comparison of the examination methodologies presented in available identified articles was carried out. Five approaches to identifying geographical contradictions and uncertainties in regional digital development strategies have been identified. According to the main method of expert examination, these approaches are called comparative geographical, cluster, convergent, geopolitical and limological. Nine strategies are listed, among which most publications are devoted to the European document «Digital Agenda». A brief definition is presented, examples of implementation are given, and the main advantage and several main disadvantages for each approach are indicated. It is shown that further research on the issues under consideration may be related to the elimination of the identified shortcomings, the development of new approaches, coverage of new strategies, the geographical verification of the simultaneous implementation of several strategies for the same group of regions, the adaptation of the methodology for identifying geographical contradictions and uncertainties in the digital development strategy of one country for the examination of the strategy of another country, the identification of spatial effects from the implementation of strategies, and the integration of all approaches into a single methodology of geographical expertise. The results can be used to adjust existing and develop new regional development strategies.

We suggest a method of assessing the presence of groups of years with low, medium and high discharges in the flow of major rivers in Asian Russia for a particular observing period. The river discharge was associated with a particular group of discharge by using its average long-term value. The years with discharges smaller than 0.95 or larger than 1.05 of its average long-term value were referred to low or high discharge rivers, respectively. The years with medium discharge included the values of discharge which varied from 0.95 to 1.05 of the average long-term value. It was found that the discharges of the eight major rivers of Asian Russia (Ob, Yenisei, Lena, Yana, Indigirka, Kolyma, Amur and Kamchatka) relatively often include groups of rivers with different discharges: low, medium and high. Most often the length of these groups varies from two to five years. However, the runoff of the Amur river showed groups of low and high discharges with a length of 10 years. The discharge of the Indigirka river showed one group with a length of nine years. The proportion of groups with a length of one year, which are not included in groups of years of different discharges, with respect to the total number of years made up: Ob - 23,5 %, Yenisei - 45, Lena - 43, Yana - 28,8, Indigirka - 26,7, Kolyma - 30,2, Amur - 38,7, and Kamchatka - 36,1 %. The probability change of years with a particular discharge for other discharges was assessed. It is established that in the runoff of the rivers of Asian Russia the probabilities for years with low and high discharges only to persist are the highest.

A study of the problems of transport and energy components in the costs of the economy of Siberia and the Far East is presented. The influence of geographical factors on the production costs of enterprises in the subjects of the Russian Federation located on the territory of the macroregions: Siberia and the Far East is analyzed. Huge spaces and infrastructurally undeveloped distances derived from them, and extreme temperature conditions for most of the year make it fundamentally important to assess the transport, communication and energy components of economic activity in these macroregions. Territorial differences in transport and fuel and energy costs in the Siberian and Far Eastern subjects of the Russian Federation are considered. Since these items of expenditure are derived from climate and geographical location, together they are considered as the main component of geographical costs. A calculation was carried out both in the fractional and in the specific dimension, followed by the integration of the resulting values in the form of an index from 0 to 3. For the spatial analysis of the integral index and its terms, a series of maps was compiled. It is established that the geographical location and specialization of the region affect both the total share of energy costs (its fuel and electricity components) and transport in total production costs, and their structure. The types of transport and energy cost combinations are highlighted: absolutely extreme; fuel increased, high and extreme; electric high and extreme, and transport high and extreme. The approach presented in this study can be used to optimize the siting of productive forces in Asian Russia.

The problem of significant territorial differentiation of the demographic rates in Siberian regions is considered. The relevance of the topic is determined by significant interregional disparities in socio-economical development, and in the level and quality of life of the population of the Siberian macroregion. The socio-demographic potential was evaluated by using different statistical rates of population reproduction. The rating of 16 regions of Siberia was formed according to 10 demographic rates, on the basis of which the grouping of the Siberian territory by favorableness of the socio-demographical potential was prepared. Significant territorial disparities in the coefficients of natural and migration growth, infant mortality, demographic loads, average age, and the proportion of men and women in the structure of population were revealed. The northern Siberian resource regions with attractive economic conditions for the population were given the rate of “favorable”: Khanty-Mansi Autonomous Okrug - Ugra, Yamalo-Nenets Autonomous Okrug, Tyumen oblast, and the Republic of Sakha (Yakutia). The group with the rate of “conditionally favorable” includes the regions with similar demographic processes: the Republics of Tyva, Buryatia and Altai. The regions with a low level of quality of life and natural and migration decrease of population received the rate of “unfavorable”: Kemerovo oblast, Altai krai, and Omsk oblast. A relationship between the identified types of population reproduction and the rate of demographic potential of the Siberian territory was revealed and cartographically visualized. It was established that the territories occupied by indigenous peoples are characterized by a significant role played in the population reproduction by specific features of demographic behavior: lower percentage of divorces, younger age of mothers giving birth to the first children, and the orientation toward families. It is concluded that economic factors, such as the size of salary and regional domestic product, are basic for forming the territorial disparities of the socio-demographic potential of Siberia.

The prospects for the development of geological tourism as one of the directions of ecological educational and scientific tourism on the territory of the Baikal area of the UNESCO World Natural Heritage sites are discussed. According to these authors, this territory can be considered as a biosphere geopark which has the necessary preconditions for creating a system of Geoparks here and raising the question of including them in the global network of UNESCO Geoparks. A specific feature of the geopolygon is its location in the central part of the Baikal rift system and in the Central ecological zone of the Baikal natural territory of high ecological and legal significance. Within the Baikal depression and its mountainous surroundings, there are natural sites of international importance. The basis for the development of geological tourism is formed by the structure of the Earth’s crust, various rocks and minerals, geological formations demonstrating the evolution of the lithosphere, mountainous dissected relief, formed under the influence of the latest tectonic movements, and the specific Baikal climate. Sites of geological tourism have been identified, a geological and recreational zoning of the territory has been carried out, taking into account the features of the geological structure, terrain, the degree of complexity of engineering and geological conditions, the presence and location of unique and valuable geological objects. Geological tourism is considered in the biosphere context, according to which geological processes and phenomena are positioned against the background of ecosystems characterized by high rates of self-healing potential and attractiveness: a special aesthetic and emotional-cognitive attractiveness. This allows the various types of educational and scientific tourism to be combined. The adopted noospheric paradigm involves a high scientific, technical and educational level of training for the development of geological tourism, and ensures the attractiveness and stability of geological objects against the background of living nature. The prospects for further research related to the provision of ecosystem services for organizing and conducting geological excursions and routes have been identified.

The largest cities of the Baikal region, Irkutsk, Ulan-Ude, and the capital of Mongolia Ulaanbaatar are analyzed in terms of the level of their landscaping, the formation of a green framework and the preservation of natural complexes. The assessment of the quantity and quality of landscaping is carried out by using the ideas of territorial nature conservation as well as taking into account the current standards of urban planning documents, which is the main purpose of this article. An attempt is made to give a detailed indication of the composition and area of the elements of green zones, their classification, institutionality, functional purpose, condition, level of protection, sufficiency of landscaping, and comparative characteristics of cities. The potential of each of the cities and its components are shown in the form of area characteristics and digital estimates of urban green zones, and their relationship with normative indicators. A classification of the types of green spaces of the cities has been developed, highlighting specially protected natural areas in accordance with special laws; urban forests and other similar areas determined by resolutions of the city authorities; managed by special municipal entities but not having a special status of green objects; as well as areas important for the greening of the city, but neglected by the city administration. Alternative components of urban greening in the form of territories occupied by cemeteries are highlighted. A so-called brown part of the ecological framework has been defined in the form of industrial, transport and warehouse zones, garage cooperatives, and landfills. The situation of the not obvious sufficiency of the total indicators of the urban greening area and the problems of compliance with regulatory documents on urban planning at the level of residential microdistricts of existing and new buildings is discussed. The task of strengthening the links of the nodes of the “green framework” of the cities is declared as well as the importance of the transition from quantitative to qualitative indicators of landscaping.

An assessment was made of the correctness of using automatic thermographs DS1922L-F5 and thermohygrographs DS1923-F5 in monitoring air temperature and relative humidity in mountain-depression landscapes by comparing data obtained with loggers and standard psychrometric thermometers installed at the Tunka weather station (Republic of Buryatia). A comparative analysis was carried out by using standard statistical methods. It was found that the differences in the readings of the instruments do not exceed the instrumental error of temperature measurement (0.1 °C) in 75 % of cases, and the error in relative humidity measurements (5 %) in 98 % of cases. In analyzing the daily average values, these ranges increase to 80 and 100 % of cases, respectively. The correlation coefficients between data obtained by standard meteorological instruments and compact automatic loggers are higher than 95 % both for temperature and for humidity. Based on the results of the study, the conclusion was drawn regarding the correctness of the use of these instruments in microclimate monitoring. Since 2007, air temperature and humidity measurements have been made at 56 model sites, synchronously with observations at weather stations of Roshydromet. The peculiarities of the temperature regime and the regime of relative humidity of the mountain-depression landscapes of the South-Western Cisbaikalia (Tunka and Mondy depressions) were described. Statistically significant differences in air temperatures on the slopes and at the bottom of each of the depressions in individual months and over a year, and also the differences in the temperature regime between the depressions, due to the structure, area, relative height and depressions coefficient, are shown. In average annual values, the temperature difference between similar landforms in two depressions is about 2 °C. The same order of magnitude is shown by the microclimatic differences between the slopes in each of the depressions.