Home – Home – Jornals – Geography and Natural Resources 2022 number 1

The effect of non-conducting extended inclusions (cracks) on the electrical conductivity of a conductive medium at direct current was studied using a two-dimensional model. The additional electrical resistance due to the presence of cracks was calculated using the hydrodynamic analogy between potential flow of an ideal incompressible fluid around solids and electric current flowing around cracks. The dependences of the relative additional electrical resistance of the material on the fracturing coefficient in various limiting cases were determined. Their correctness is confirmed by the results of numerical analysis of the obtained expressions for various fracturing coefficients of the sample for thin and thick samples. The cases of parallel cracks and cracks randomly oriented in different directions were investigated.

This paper presents a study of the thermal and thermally stressed state of a reactor in the form of a quartz cylinder filled with tin for producing hydrogen by methane pyrolysis. When determining the temperature state, the problem for the two-layer structure (quartz-tin) using the Heaviside function was reduced to the problem for a single-layer structure with variable (piecewise homogeneous) properties of the material. An analytical solution including algebraic polynomial functions with coefficients exponentially stabilizing in time was obtained by determining the position of the temperature disturbance front and additional boundary conditions using the integral method of heat balance. Using the obtained solution, quasi-static temperature stresses were determined in the case where the structure is a two-layer hollow cylinder (flat deformation). The layer conjugation method was used to obtain an exact analytical solution of the thermoelasticity problem, from which it follows that at the point of contact of the layers, the hoop and axial stresses have a jump (discontinuity) with a change of sign in it. It is found that in certain start-up modes, the hoop and axial stresses can exceed the tensile strength of the quartz layer. The results were used to determine start-up modes in which the stresses do not exceed permissible values.

Based on the nonlocal strain gradient theory, the transverse vibration of a viscoelastic graphene sheet subjected to an in-plane magnetic field and external forces is studied. A general governing equation for the graphene sheet vibration is formulated. Theoretical solutions for undamped and damped vibrational frequencies are obtained. The influence of the in-plane magnetic field on the damping ratio and on the frequencies of the free and forced vibrations is studied within the framework of the nonlocal strain gradient theory.

Nonlinear parametric oscillations of a longitudinally reinforced orthotropic cylindrical shell filled with a viscous liquid are studied. Fluid motion is described using a linearized Navier-Stokes equation. Equations of motion for a reinforced orthotropic shell filled with viscous liquid are obtained based on the Ostrogradsky-Hamilton principle of stationary action. The dependences of the ratio of the nonlinear frequency to the linear frequency on the deflection of the shell are determined for different numbers of reinforcing ribs.

In this paper, a progressive damage analysis of two-dimensional C/SiC composites and superalloy mechanically fastened joint with a countersunk bolt is implemented to simulate the uniaxial tensile loading process by using a user-defined subroutine UMAT embedded into the general package ABAQUS. On the basis of the developed damage model, a parametric study is carried out to illustrate the effects of countersunk parameters on tensile performance for the hybrid bolted joint. It is found that there are negligible changes in the stiffness of the bolted joint, as the countersunk height varies from 1.5 to 2.5 mm for the considered bolt-head diameter cases. However, the failure load of the ceramic matrix composite and superalloy hybrid joint exhibits significant changes under different combinations of countersunk parameters. Increasing the countersunk height of the bolt intensifies the initial stress concentration and results in the redistribution of stress around the hole-edge area of the composite material plate. For the bolt-head diameter and countersunk height equal to 9.4 and 1.5 mm, respectively, the joint structure ensures the maximum load-bearing capacity for the studied joint with a countersunk bolt.

The article deals with the problem of establishing regional financial centers as a foundation for stimulating financial development in the regions in question. It puts forward a hypothesis about the need to create conditions for the financial development of federal districts based on the potential of financial market participants (issuers, investors, financial intermediaries, infrastructure organizations, regulatory and self-regulatory bodies), which would stimulate investment activity in the regions. We discuss models to form financial activity centers and substantiate a comprehensive one built upon institutional and instrumental approaches. The use of these approaches is justified with a view to introducing financial “afterburner" in Russia. As applied elements of the study, we have designed directions for a roadmap within each of the approaches (institutional and instrumental) to establish regional financial centers in Russia’s federal districts. The research relies on a representative statistical sample that allows assessing the current potential of participants in the Russian financial market as well as in individual federal districts.

Electronics is one of the critical industries that have a great impact on the social and economic growth of the industrial areas. The work aims to assess the spatial development of electronic production in the regions of Russia. To achieve this goal, we highlight the main development indicators of the electronic industry and provide the structure of the main types of electronics produced in the regions of Russia. Microelectronics sets the pace for the development of the electronics industry. The lack of indicators for microelectronics growth in the Development Strategy for the Electronic Industry of the Russian Federation until 2030 makes it difficult to assess the effectiveness of its implementation. Our study tests a hypothesis whether it is possible to consider an integral indicator for assessing the localization of integrated electronic circuits production as an end-to-end indicator for the microelectronics spatial development. For this purpose, we have designed an integral indicator against the structural peculiarities of the industry. The feasibility of the applied approach defines the need to take into account both physical and intellectual productions of microcircuits as the primary products of fabless manufacturers. By testing the designed integral indicator under current conditions in Russia, we managed to establish the development levels of microelectronic production located in the federal districts of Russia. The results obtained may be used to draft and adjust state programs and strategies for the development of the Russian electronics industry and the spatial development of Russian regions in general.

The article presents the results of the analysis to determine the volume and directions of migration flow of the population to the nine Arctic regions of Russia. It identifies labor surplus constituent entities of the Russian Federation relying on statistics on the state of regional labor markets and tests the hypothesis about the role of labor surplus regions in supplying the Arctic with human resources. The analysis draws on official statistical reports by Rosstat on inter-regional migration of the people aged 14 and over. We examine the qualitative aspects of migration to the Arctic through the reasons why migrants change their place of residence, as well as their level of education. Based on aggregated information, it is possible to construct the structure of migration flows into the Arctic regions using statistical analysis methods. The findings suggest that the 15 labor surplus regions account for only a small share of the total migratory flow to the Arctic. At the same time, it has been found that labor surplus regions, unlike other regions of Russia, are characterized by a positive balance of migration to the Arctic. The example of the Republic of Dagestan shows that the regions of the North Caucasus can act as suppliers of labor resources for the Arctic regions of Russia. Here we also identify 15 Russian regions of origin of the most migrants arriving in the Arctic each year. The results of this study will be of use to the relevant authorities, especially to implement human resources policies aimed at attracting workforce to the Arctic regions.

The article provides an overview of interpretations of the concept of human capital suggested by international and Russian researchers. There is no consensus about human capital, which leads to numerous approaches to its measuring and assessing and requires further discussion since the issue is complex and multifaceted. The problem posed and the subject of our research require that it is necessary to supplement and expand the toolkit to improve the quality assessment of the indicator under study. The paper uses an indicator method for assessing the level of human capital. We use the following factors as indicators: population, health, the standard of living, employment, living conditions, education, safety, and ecology. Each factor includes a specific list of indicators. The article interprets the values of the human capital level and introduces a new term, “criterion for assessing the quality of human capital level." As a database for analyzing and assessing the level of human capital, we rely on regional statistical information. The research testing ground is Arkhangelsk Oblast, along with the Nenets Autonomous Okrug and the Northwestern Federal District regions. The results of this study may help regional bodies in charge of territorial development and be of use in designing strategies for the development of Russia’s constituent entities.

One of the leading factors in the development and efficiency of the innovation economy is human capital. The competitiveness of a country’s economy directly depends on its ability to develop, preserve, and accumulate human capital. The economy of modern developed countries is primarily characterized by high quality and level of human capital and considerable investment in its development. The primary purpose of our research is to study human capital as a concept underlying the strategic guidelines of social and economic development of the Republic of Tatarstan. The law of the Republic of Tatarstan, “On Approval of the Strategy for Socio-Economic Development of the Republic of Tatarstan until 2030,” has been chosen as the fundamental information source. The research objectives are met by using content analysis as a qualitative-quantitative method of studying the content of text arrays. We apply two types of content analysis during the research: non-quantitative and quantitative. Based on non-quantitative content analysis, we construct a non-frequency model of the text content from the Republic’s strategy for socio-economic development in view of the human capital concept. On the other hand, quantitative content analysis allows us to record, describe in quantitative terms, and meaningfully interpret the categories most relevant for the study purposes: human capital, human potential, labor resources, and labor potential.

Given that rural settlement patterns actively transform due to a depopulating village network, agglomeration and urbanization processes, mass migration from suburbs and concentration of population in large cities, rural territorial systems demand to resolve the spatial organization of individual living environments. In particular, fewer residents and settlements render the educational system inefficient, both in terms of how much the educational process costs and how it is organized. In this regard, the issues of educational system logistics associated with optimizing schoolchildren’s transportation flows between settlements and planning the placement of social elements by territory are highly relevant. The article analyzes the existing spatial organization of the educational system in rural areas of a municipality as illustrated by Elabuzh municipal district in the Republic of Tatarstan. Based on analytical study findings, we designed alternative models to organize a general educational system, which were then cross compared by performance indicators. The models built upon cluster formations with passenger turnover minimization have proved optimal; they allow us to determine the accommodation options with moderate costs and low transport load on the transported children. Another mechanism of traffic flows optimization is bound to developing the existing transport infrastructure so that a new level of the system’s spatial organization may become attainable. The results of this study can be applied in regional (municipal) management, forecasting and design, spatial and urban planning.

The article presents the results in a study of Russian agro-industrial regions as a special group of territorial socio-economic systems with the features of economy and social sphere development and problems of prospects forming. The presented results complement the materials previously published in “Region: Economics and Sociology " (2019, No. 2), which reveal the specifics of the development of agro-industrial regions in statics. The purpose of this article is to identify changes in composition of agro-industrial regions, as well as dynamics of their socio-economic and demographic development for almost three decades. We describe a methodology and results of the transformation that the territorial and sectoral structure of the Russian economy underwent. The article studies the shifts in the territorial and sectoral structure of the Russian economy, evaluates the changes that have occurred in each type of region, and characterizes the level and dynamics of the gross regional product of the agro-industrial regions. We consider the socio-economic and demographic dynamics of the agro-industrial regions against the background of Russia. The population incomes, poverty, and inequality in the agro-industrial regions are described depending on the economic period characteristics. Regional differentiation for these indicators is assessed. The agro-industrial regions demonstrate the heterogeneity of demographic space. Regional grouping is proposed in terms of the level and nature of demographic development. The research reveals how the regions demographic characteristics depend on their centro-peripheral position. We present an integrated estimate of the well-being dynamics of the agro-industrial regions on economic, social, and demographic indicators. On the one hand, they show a lack of correlation between the economic and social well-being in regions; on the other hand, the demographic well-being is not associated with those as well. The study concludes with exhibiting the unique traits of each agro-industrial regions.

The budgetary policy is among the main tools for managing local development. Its effective implementation contributes to budget replenishment, allowing regions to increase expenditures on social and economic measures. This study aims to analyze the most important directions that state policy takes to fund the activities of local self-governments in large cities and to study the impact of budgetary policy on the development of urban areas with at least one million inhabitants. The paper considers the primary fiscal indicators for the largest cities of the Russian Federation; assesses the structure of budget revenues to identify, on the one hand, how sufficient tax and non-tax revenues accumulated in cities and credited to their budgets are and, on the other hand, how dependent city budgets are on grants from the budgets of their respective regions; and carries out a detailed analysis of urban budget expenditures. Since the city of Novosibirsk is the largest municipal entity in Russia, this article takes a close look at its budget specifically. By calculating fiscal coefficients, we study the city’s budget stability and reveal its stance both among the other largest cities of the federation and urban districts of Novosibirsk Oblast. We analyze in greater detail crucial revenue items for Russian cities with a population of over one million, both accounting for their own tax and non-tax revenues and considering gratuitous transfers to urban budgets from regional ones. The article concludes that it is necessary to secure stable income tax sources to local budgets in general (and to cities in particular) to enhance their tax potential. We have noticed that between 2011 and 2018, urban areas with over a million inhabitants had the significantly poorer fiscal capacity and were less self-sufficient in terms of their revenues. Moreover, we have examined the main expenditure items for the largest Russian cities to determine whether they correspond to the socio-economic development goals of cities with over one million inhabitants. In Russia, such cities must be separated from the total population of municipalities as they act as the country’s growth drivers and have a decisive impact on its economy. Large cities need tax sources of income sufficient for their stable functioning and the formation of development budgets secured legislatively and at the federal level.

This article examines the positions of large cities (250-1,000 thousand people) and towns (100-250 thousand people) in regions’ economic space drawing on the example of the Ural macro region. We assess spatial significance in terms of specific weights in population size, investment, the volume of manufacturing output, retail trade turnover, and the commissioning of residential buildings. All indicators are found to have disproportions, which testifies to a violated spatial structure and a deformed economic space. Large cities and towns in the Urals are characterized by low population density, and their shares in the retail trade turnover and the commissioning of residential buildings are lower than shown by demographic indicators. The traditional industry is the only proverbial “anchor" that maintains the existing settlement structure. Compared to 2007, 2017 saw the spatial significance of large cities and towns in the Urals decreased. Such urban localities cease to function as trade and service centers for neighboring regions. Preserving the status quo poses the risks of growing imbalance in the national economic space and requires the advanced development of large cities and towns.

In this review, we aim to analyze the development and mutual influence of the ideas of efficiency and equality in spatial development, the reflection of these ideas in competing concepts of regional policy from the 1990s to the present day, drawing on the three literature strata. The first stream of publications captures the debate about the role of space in an era of globalization and revolutionary changes in how information transmits. The polar hypotheses - from the “death of space" to the “tyranny of space" - have stimulated empirical assessments of the impact that distance has on the level of economic interactions, which have not confirmed the thesis of a “flat world" where economic activity is distributed evenly. At the same time, dissatisfaction with the results of traditional redistributive regional policies matured in the expert community, giving rise to the second stratum of literature: a debate between the proponents of “space-neutral" and “place-based" policies. The former focuses on urban agglomerations as sources of growth, while the latter seeks to unlock the underutilized potential of each place. The discussion clarified the possible implications of these approaches for national economic efficiency and the reduction of regional inequalities. Recognizing the value of each place has brought forth a new requirement for the place-based policy to be “place-sensitive”. A similar discussion about the directions that the spatial development of Russia’s economy takes, and the principles of regional policy developed simultaneously in the Russian-speaking segment. The territorial concentration of growth in cities and the ways to reduce interregional inequality became major talking points. The peculiarity of such a debate was that it took place around the changing versions of spatial development strategies, often based on opposing principles.

Results of numerical simulations of reacting turbulent flows in a channel with a rectangular cross section and sudden expansion (backward-facing step) are reported. The simulations are performed for test conditions in a high-enthalpy hotshot wind tunnel with the Mach number at the channel entrance M = 3.85. Hydrogen is used as a fuel; it is injected transversely to the main flow ahead of the step from the upper and lower walls of the channel. The computations are performed in an unsteady three-dimensional formulation with the use of the Fluent 2020R1 software with reactions of hydrogen combustion in air being ignored or taken into account. The structure of reacting turbulent flows is studied; the flow parameters at different stages of the unsteady process of ignition and flame stabilization are determined. The computed data are compared with the results of an experiment in which the static pressure distribution over the channel walls were measured. It is demonstrated that the simulations correctly predict the unsteady pattern of ignition and flame propagation along the channel.

To reveal the influence of vent parameters on the dynamic mechanism of an external explosion induced by a vented premixed methane-air explosion, the evolution process of an outdoor flow field under different vent opening pressures ( p_v ), opening times ( t_v ), and scaled vent size ( K_v = A_v / V ^2/3) is studied by methods of computational fluid dynamics. With an increase in K_v , the shape of the unburned gas cloud and vented flame gradually changes from a jet shape to a depression toward the vent. The outdoor peak specific turbulent kinetic energy increases by 36.5 and 4 times with an increase in p_v and t_v , respectively. At t_v = 0.1 s, the peak specific turbulent kinetic energy reaches 1 411 m²/s² and the turbulence range reaches 3 times the length of the room. With an increase in p_v , t_v , and K_v , the occurrence time interval of the external explosion exhibits a decreasing trend. The external explosion is located at a distance of less than 1.4 times the length of the room. At K_v = 0.05, the external explosion occurs at the furthest location.

Regimes of continuous multifront detonation in a methane mixture with heated air in a flow-type annular combustor 503 mm in diameter are obtained and studied for the first time. Air is preheated by straight firing from 600 to 1 200 K in the settling chamber by means of burning a stoichiometric hydrogen-oxygen mixture entering the combustor; the air flow rate is 6 ÷ 20.9 kg/s. The fuel (methane)-to-air equivalence ratio is 1.15 ± 0.1. The influence of the air heating level on the domain of continuous detonation, pressure in the combustor, and specific impulse is analyzed. Regimes of continuous multifront detonation with one pair of colliding transverse waves with a frequency of 1.2 ± 0.1 kHz are observed in all experiments at air temperatures ranging from 600 to 1 200 K. Based on the stagnation pressures measured at the combustor exit, the specific impulse of continuous detonation is determined as a function of the air flow rate and its temperature. As the air heating temperature increases, the specific impulse of the thrust force is found to decrease owing to the increase in the degree of dissociation of the detonation products. The maximum specific impulse with allowance for the heated air energy, equal to 1 630 s, is obtained for the air temperature in the settling chamber equal to 600 K.

The use of nanosized metal powders is a promising direction in the development of modern energy compositions due to their high reactivity and intense heat release upon contact with an oxidizer and during combustion. The results of a combined TG-DSC analysis of Alex aluminum nanopowders and a Al-Cu compound, obtained via electrical explosion of conductors, are presented at constant heating rates of 2, 4, and 20 °С/min in air in a temperature range of 30 ÷ 1 300 °С. It is revealed that Alex and Al-Cu nanopowders are intensely oxidized when heated in air to a temperature of 600 °С due to the oxidizer diffusion through the porous oxide layer Al₂O₃ and the possible formation of open surfaces of an active metal during a phase change in the crystal lattice of the metal oxide. The Friedman and Kissinger-Akahira-Sunose (KAS) methods were used to obtain dependences between the activation oxidation energy on the degree of conversion (oxidation) of nanosized metal powders. It is shown that the activation energy of Alex and Al-Cu nanopowders depends on the degree of conversion (oxidation stages) and lies in ranges of 78 ÷ 307 and 99 ÷ 430 kJ/mol, respectively.

This paper describes a study of the effect of a Fe + Co + Cr + Ni + Al metal binder content and mechanical activation (MA) on burning rate, maximum combustion temperature, the elongation of samples during combustion, the mixture yield after MA, the size of composite particles after MA, and the morphology and phase composition of combustion products in a Ti + 2B + x (Fe + Co + Cr + Ni + Al) system. Self-propagating high-temperature synthesis (SHS) is used to obtain a composite material consisting of ceramics and a high-entropy alloy. The MA increases from 60 to 80 % the maximum content of a metal binder in the mixture, at which SHS is carried out at room temperature. The addition of a Fe + Co + Cr + Ni + Al binder to the activated Ti + 2B mixture prevents mechanochemical synthesis from proceeding during 5-min long MA.

This paper describes the combustion of 90 % (Ti + C) + 10 % Ni and 80 % (Ti + C) + 20 % Ni granular mixtures with a binder (polyvinyl butyral) content of the order of 1 %, used to obtain composite materials. Experimental data and calculations show that combustion waves in grains of fractions of 0.4 ÷ 0.8, 0.8 ÷ 1.2, 1.4 ÷ 2, and 0.6 ÷ 1.6 mm propagate in the conductive mode. The micro- and macroscopic characteristics of combustion (namely the combustion transfer time from one granule to another and the burning rate of the granule substance) are calculated on the basis of the experimental burning rate of granular mixtures from granules of different fractions for the first time. The combustion transfer time from one granule to another for mixtures with 10 and 20 % Ni turns out to be the same for all fractions: approximately 0.006 s. Regardless of the granule size, X-ray diffraction patterns of combustion products contain only TiC and Ni phases. Brittle agglomerates easily crushed under laboratory conditions are obtained as a result of the synthesis. The resulting data indicate the possibility of possibility of safe scaling of the process of obtaining (Ti + C) + x Ni cermets with a Ni content of 10 and 20 % in the combustion mode from a granular charge with granule sizes up to 1.7 mm.

The synthesis of an intermetallic compound in a mixture of Ni + Al + Al₂O₃ powders with an inner metal plate oriented in the direction of propagation of the combustion wave has been studied by experiments and theoretical calculations as applied to the problem of self-propagating high-temperature synthesis of functionally gradient materials. Copper, titanium, and steel plates are considered. The propagation of the exothermic reaction front is analyzed for various thermophysical characteristics of the inner metal layer. In samples with a copper plate, the combustion front near the contact boundaries is stretched in the direction of the combustion wave. Increase in the average burning rate of the sample with the heat recovery effect is observed when using copper plates 1 ÷ 3 mm thick. During combustion of samples with titanium and steel plates, there is a deceleration of combustion wave propagation along the contact boundary.

Dioctyl sebacate (DOS), paraffin (PW), fluororubber (FR), and polyurethane (PU) are widely used as binders in aluminized propellants and explosives. In this study, ignition and combustion of aluminum powders coated with DOS, PW, FR, and PU are investigated. The flame speeds of the aluminum powders coated with DOS, PW, and PU are found to decrease with an increase in the content of these binders. The flame speed of the aluminum powder coated with FR is greater than those of the aluminum powders coated with DOS, PW, and PU. In this case, combustion improvement is due to the reaction between the alumina shell and FR.

The combustion of a mixed metallized solid fuel containing boron particles is numerically studied. The mathematical model is based on the approaches of two-phase reacting medium mechanics for describing processes in a two-phase flow above the fuel surface and the Hermance model for describing the decomposition of a mixed solid fuel. The model of combustion of a mixed metalized solid fuel takes into account the oxidation and combustion of boron particles. The dependence of the burning rate of a metallized mixed solid fuel on the gas pressure above the combustion surface and the size of boron particles is determined from a parametric study.

The destruction of an energetic condensed system based on glycerol trinitrate, polyether urethane, and an aluminum powder from exposure to a relativistic electron beam with a maximum energy of 310 keV, a total duration of 170 ÷ 180 ns, and an average flux density of 200 ÷ 215 J/cm² was studied by nanosecond electron-optical chronography, scanning electron microscopy, and energy dispersive analysis. The effect of the generation of pulsed electric fields and shock-wave loads accompanying relativistic electron beam absorption on the mechanical damage in samples of energetic condensed systems is discussed.

The values of the detonation velocity in thin layers of the VS-2 pyrotechnic composition are given. The Jones-Wilkins-Lee equation of state parameters of explosion products were determined. The obtained equation of state was used to perform numerical calculations and comparison with the experimental parameters of the air shock wave formed upon initiation of the VS-2 composition. Computational and experimental studies were carried out to determine the dependence of the pressure pulse on the thickness of the VS-2 layer. The dependence of the specific pressure pulse of the explosion products on the surface density of the VS-2 composition was determined.

A method of constructing the curve of cold compression and the isotherm for the metal based on the generalized equation for the Gruneisen coefficient is considered. In contrast to available approaches, it is proposed to take into account the change in the character of interaction of atoms in the crystal due to compression. For this purpose, the dimensionless parameter t in the generalized equation is considered as a function of compression. The experimental data on metal compressibility testify that the parameter t increases with an increase in density. Free parameters of the model for aluminum are found. The proposed approach allows the aluminum isotherm to be described more accurately and in a wider range of density. For the cold compression curve, the working region of the model increases almost by an order of magnitude in terms of density and by more than two orders of magnitude in terms of pressure (as compared to the model where the parameter t is assumed to be constant).

Honeycomb ceramic-metal catalysts were studied before and after stability tests in a coal fluidized-bed reactor with a capacity of 3 Gcal/h. The catalysts were studied by X-ray phase analysis and scanning microscopy with elemental analysis; their textural and strength characteristics were studied. The test reaction of octane oxidation was used as a measure of catalytic activity. A 30 ÷ 40 % decrease in activity was found with decreasing strength from 26 to 18 MPa. Based on the obtained changes in properties, the time of possible operation of the catalyst was predicted to reach at least two winter seasons.

This paper presents an analysis of the hydrodynamic and physico-chemical features of flow and combustion in a low-emission combustion chamber (LECC) which differs from other combustion chambers in design and combustion modes of a lean air-fuel mixture. The influence of the composition and residence time of the mixture in the LECC on the emission of NO _x and CO was considered. The organization workflow was proposed, and an LECC prototype was developed whose emission level of NO _x and CO less than 5 ppm is 2 ÷ 5 times lower than that in available LECCs. The results of experimental studies of the LECC prototype with variations in flame temperature, pressure, and residence time in the LECC confirm the validity of the proposed solutions.

This article deals with the categorization of Russia as the continental type of countries typical of classical geopolitics and the concepts based on its approaches. An analysis is made of the main aspects of continentality of countries: the territorial, populaton distribution and activity aspects. A number of indicators have been proposed to reflect these aspects. The resulting sample of countries, including Russia, are characterized according to the degree of continentality based on these indicators. It is pointed out that in terms of transport and geographic continentality, the number of seaports, the cargo turnover of the country’s largest port and the location of the capital city relative to the sea, Russia should be classified as a continental country. In terms of the ratio of sea and land borders, the potential of the Navy, the number of merchant ships and fish catch, Russia should be assigned to the oceanic type of countries. It has been determined that integrally Russia can be assigned to the transitional continental-oceanic type. A positive correlation was found between the number of merchant ships per capita and gross domestic product per capita, exports per capita and life expectancy. This correlation shows (confirms) that the more continental a country is, the less economically developed it normally is. It is noted that within the framework of classical geopolitics, the classification of Russia as a continental country is associated with the concept the difference between «sea» and «land» which gives rise to international conflicts. A departure from the idea of explaining the conflict between Russia and the West by these geographical factors also entails a rejection of the image of Russia as a purely continental country. The use of military-political and economic advantages of both the sea and continental location was characteristic of Russia in the past and is relevant at present.

This article considers the deterioration trends in structure and quality of the oil-producing regions of Russia and systematizes the criteria for distinguishing the category of hard-to-recover oil reserves in the domestic literature. We investigated the characteristics of the resource base of hydrocarbons and their impact on the innovative development of the oil-producing regions of Russia. A unique information base for study of resource regions has been compiled: total recoverable reserves, the share of small and very small deposits, the average size of the deposit, and degree of exploration are among the resource factors; the factors of the fluid property included the contribution from dense, sulphurous and viscous oil, and the oilfield factors involved water cut and the degree of depletion. The analysis included the factors of regional innovative development: the share of innovative goods in the volume of shipped products, the work done and services rendered, the share of technological innovation costs, and the share of internal research and development costs for gross regional product. Thus the hierarchical clustering method has been used to classify the oil and gas regions of Russia according to the quality and structure of the resource base, as well as to the level of innovative development. Calculations identified three clusters (groups of regions): one cluster included regions with a high degree of innovation and a high degree of hard-to-recover reserves, the other cluster involved regions with a medium degree of innovation and a low degree of hard-to-recover reserves, and the third cluster included regions with a low degree of innovation and a moderate degree of hard-to-recover reserves. This study verified and confirmed the hypothesis that a low quality of the resource base of hydrocarbons in oil-producing regions of Russia stimulates innovative development. The results of the study indicate that production of hard-to-recover oil has an extensive innovative component which has a multiplicative effect on the related industries and economy of the regions as a whole.

The synchronism and asynchrony of variations in the annual runoff of 18 major rivers (153 pairs of the rivers) in the Asian part of Russia were estimated by the new original methodology. The methodology is based on taking into account three groups of water discharges of the rivers (years of low, moderate and high water discharges) and on the numeric rating of the runoff in the years being compared. The runoff of the rivers is assigned to a particular group of water discharge by using its mean value over many years. The years in which the runoff was less than 0.95 of its mean value over many years were assigned to the years of low water discharge, and the years with the runoff larger than 1.05 were assigned to the years with high water discharge. The years with moderate water discharge included the values of the runoff in the interval 0.95-1.05 of the multiannual mean value. The runoff of the years with low, moderate and high water discharge was identified by number 1, 2 and 3, respectively. A comparison of water discharges was made for all 153 pairs of river basins for the correlative periods of observation under investigation. The years with identical water discharges (1 - 1, 2 - 2, 3 - 3) were assigned number 1; the years with opposite water discharges (1 - 3, 3 - 1) were characterized by number -1, and the years with adjacent water discharges (1 - 2, 2 - 1, 2 - 3, 3 - 2) were identified by number 0.5. For each pair of the rivers we estimated the numeric sum expressed in fractions of the total period of observation: the parameter of synchronism (asynchrony) of variations in the runoff. For 18 pairs of river basins the values of the parameter of synchronism were equal or exceeded 0.5. For these pairs of the rivers it was determined that the contribution from the years of low, high and a moderate discharges to the synchronism averaged 45.1 %, 36.3 and 10.7 %, respectively. The years with adjacent discharges showed an increase in the synchronism parameter by 29.2 %, whereas the years with opposite discharges decreased the synchronism by 21.3 %. The synchronism was also assessed by using the method of correlation.

Results of a paleobotanical (paleocarpological) layer-by-layer study of three peat sections located near the Pogorel’skii Bor experimental station operated by the Institute of Forest SB RAS (the interfluve of the Buzim and Sukhoi Buzim rivers) are presented. The study area is located in the transitional zone between subtaiga grassy small-leaved and coniferous forests and the Krasnoyarsk non-zonal forest-steppe. The climate of the region is extreme continental, moderately warm and insufficiently humid. The objects of paleocarpological analysis were macrofossils (macro-residues of fossil plants (generative and vegetative parts of plants)). Data from each section were used to construct carpograms (histograms showing the quantitative distribution of macro-residues in the identified fossil complexes, in accordance with the section stratigraphy). As a result of a comparative analysis of the species composition of paleocarpological complexes, taking into account the data on radiocarbon ¹⁴C dating (nine dates), the evolution of the vegetation cover of the territory of Pogorel’skii Bor was reconstructed by using hypsometric levels and seven time intervals, starting in the second half of the Atlantic period of the Blytt-Cernander chronological scheme of the Holocene. On this basis, digital maps of paleophytocenoses were compiled. An analysis of the formation of vegetation over the last 6000 years has shown that in the first half of the period under consideration the birch-larch forest-steppe with an alternation of shallow lakes prevailed on the territory. The onset of cooling and humidification (5000-3500 BP) contributed to the development of a subaiga forest-vegetation complex with the involvement of dark coniferous species. The subsequent warming (3500-3000 and 1300-800 BP) contributed to the return of forest-steppe and the development of steppe complexes. The leading tree species in the first half of the period under consideration were Siberian larch and birch, and, later, Scotch pine. A decrease in the role of larch, and an enhancement of the position of pine and steppe elements in forest phytocenoses during a later period (300 BP) were caused by climate change as well as by the increased influence of the anthropogenic factor. The regional features of the paleoclimatic regime of Pogorel’skii Bor forest in the latest Holocene are highlighted.

This study aims at the description of the long-term dynamics of tritium content in atmospheric precipitation and in surface and ground water of the Lena river basin, based on new data obtained received in 2019 and 2020, and on historical information. The relationship of tritium content with the concentration of dissolved chemicals was analyzed. In 2019 and 2020, during the periods of winter and summer low water, 44 water samples were taken from the Lena river, its large, medium and small nonfreezing tributaries, interpermafrost and subpermafrost groundwater, snow cover and liquid precipitation. Data on tritium concentrations in the upper and middle Lena river and its tributaries are reported for the first time. Tritium content in samples from river water, snow cover and rain is consistent with the long-term tritium decline curve. The tritium concentration in river waters during the winter low-water period is lower than in the summer period, when tritium content in the rivers approaches its values in atmospheric precipitation, which is evidence of the contribution of groundwater to the alimentation of the rivers river feeding, in spite of the widespread occurrence of permafrost in the region. Statistically significant correlations between tritium content and redox potential, the content of bicarbonate ions, lithium and sodium ions, total dissolved solids and pH were found.

The methodology of economic valuation of ecosystem services of the marine environment is considered, which implies identification and valuation of the benefits obtained by humans from using marine ecosystems. It was found that the previously done research has disregarded and has not assessed the assimilation potential of port water areas, which consists in the absorption and dispersion of pollution arising in the course of port activities. A methodological approach is proposed for its assessment as well as an algorithm for calculating the rent-based assimilation potential by the amount of saving of expenses of economic entities that they do not pay to compensate for the damage caused or do not invest in its reduction and prevention, that is, by the amount of environmental damage caused by sea-going ships and port activities. The rent of the assimilation potential for the largest ports of Russia, the European Union (EU) and China was calculated based on the monetized metrics of environmental damage applied in the EU countries and the indicator of pollutant emissions per 1 million tons of cargo transshipments carried out in ports as well as the costs of cleaning polluted water discharged by ships. The latter value is calculated only for the ports of Russia.

The study of vegetation stability remains an important and poorly developed issue of geobotany. Results from studying of resistance to the pyrogenic factor of plant communities of vegetation cover of the North Baikal and Upper Angara depressions are presented. In recent years, fires have become catastrophic in Siberia as well as on the territory of the country as a whole; therefore, the pyrogenic impact came to be one of the main negative anthropogenic factors. We suggest an original technique for determining the parameters of vegetation resistance to the pyrogenic factor, based on assessing the ignitability. The susceptibility to fire of both individual plant species and plant layers of cenoses, and also the degree of damage by fires have been comprehensively studied, with due regard for the mesoclimatic conditions and areal distribution throughout the territory. It was established that the resistance of the communities can vary according to on their hierarchical rank. As a result of the research, a legend and a medium-scale map of the vegetation resistance in the region to the pyrogenic factor have been generated. It was revealed that the most stable communities are sparse alpine tundras, alpine meadows and meadow-swamp communities of the Upper Angara floodplain and wet forests of mountain valleys. The medium-stable cenoses include tundra watersheds and sloping summits with well-developed shrub-lichen cover, sparse communities of Pinus pumila, small-leaved forests, steppe slopes and forest communities of the floodplain. The smallest degree of stability is typical for closed P. pumila thickets, subgoletz dark coniferous-larch forests, mountain taiga dark coniferous forests, as well as for pine forests of the submontane-depression belt. An important characteristic of the stability of the communities is the duration of recovery of the primary (conventionally primary) state. It is shown that the accessibility of natural communities to humans significantly affects the resistance of vegetation to the pyrogenic factor, because this greatly increases the likelihood of fire in any of the cenoses considered.

Geoecological studies of urbanized centers of the Baikal region are aimed at identifying the specifics of anthropogenic impact on the natural environment in order to find rational solutions to environmental problems of the territories and improve the quality of life of the population. The article considers the features in the natural and ecological state of the cities of Ulaanbaatar, Ulan-Ude and Irkutsk as well as analyzing the relationship between socio-economic conditions and environmental problems of the territories.The information base of the study consisted of statistical and archival material, cartographic and literary works and data of experimental observations. The urbanized centers of the Baikal region are characterized by different socio-economic conditions, but they also have some common features of modern agglomeration processes: an intense concentration of the population in the capital cities, problems with engineering communications, and an increase in environmental tension and discomfort. The analysis revealed a high level of technogenic load from the fuel-and-energy complex and automobile transport. Natural factors, such as the atmospheric circulation, the state of natural waters and the conditions of migration of chemical elements in soils, have a significant impact on the formation of the ecological situation in the cities. Assessments of the level of anthropogenic impact on the components of the natural environment revealed extremely low conditions for self-purification of the atmosphere in Ulan-Ude and Ulaanbaatar, and the highest air pollution is recorded in Ulaanbaatar. The greatest pollution of soil cover is observed in Irkutsk, which is due to large industrial emissions and favorable conditions for the accumulation of pollutants in the soil of the territory. Ulaanbaatar is experiencing problems with the quality of water resources and drinking water supply to the population. Anthropogenic pressures on the natural environment of the cities create prerequisites for the development of diseases in the population as a result of the entry of toxic pollutants into the air and into water bodies.

Based on an extensive database, it is shown that for different limnetic regions of Lake Ladoga there occurs a temperature hysteresis phenomenon for the period of open water from May to November. The heating and cooling features of both the water surface and the integral water temperature of six different areas of the lake have been revealed, depending on air temperature of near surface layer. The approximation of dependencies between these parameters, the second- and third-degree polynomials, has shown that there are stable, meaningful relationships (p < 0.05) between them, with the determination coefficient of 0.8-0.9. Analytical dependencies allowed to calculate the increase in water temperature when the air temperature changes by one degree. On Lake Ladoga, a dependence of the rate of change in water surface temperature on air temperature is found. The biggest changes occur during the heating period. In August, at maximum air temperatures, the rate of increase in water surface temperature, especially in the deep-sea region, exceeds the rate of increase in air temperature. Canadian limnologists obtained similar results on Lake Ontario. Two important periods have been identified when the lake cools: the first one, when the surface temperature has a constant value with minimal spatial variance; and the second one, when the entire water thickness of the lake has the same water temperature with minimal spatial variance. These periods and values of water and air temperatures can serve as climatic norms in climate studies. Climatic changes in air temperature will affect the increase in water temperature in different ways in different seasons and in different areas of a large lake.

We present the results from studying the spatio-temporal organization of southern and subtaiga and forest-steppe geosystems of regions of the South of Western Siberia, including the Irtysh, Tobol, Ishim and Tobol-Tavda interfluve area, and the southern Ural, reflecting spatio-temporal variability of landscape structure in these regions, conducted its mapping, the estimation of the dynamic state variables of geosystems with the purpose of solving practical, forward-looking, environmental protection and expert tasks. The landscape structure of the study area was mapped based on the principles of structurally dynamic landscape science and the genetic classification of forest types using modern GIS technologies, including automated interpretation of Earth remote sensing data (ERS). This approach allows us to use forest taxational data in landscape studies. The geographic information landscape mapping scheme, implemented on the basis of Hansen mosaic data, made it possible to construct digital raster landscape maps of the study area, reflecting the spatio-temporal organization of geosystems and the zonal distribution of forests in the region. Automated processing of ERSdata enabled determination of the landscape structure as well as calculating the areas of different anthropogenically disturbed territories (felling areas and burning) and correlation of various types of geosystems.

Based on analyzing geomorphometric indicators of the floodplain relief of the Iya-river valley, we identified specific features in the distribution of flows during flooding within different morphological areas. A digital elevation model was used in calculating the horizontal and vertical curvature of the valley of the Iya-river, and for representing their distribution in space, maps were compiled for a number of key areas that were located within the development of the wide-floodplain, the adapted and inscribed types of channel. It was revealed that the distribution of flows within the wide-floodplain area, in addition to the width of the floodplain, was influenced by the development of segment and hollow-island floodplains, as well as the general predominance of wetland flat surfaces which are zones of accumulation, which contributed to the retention of water within this area. In the downstream section with the adapted channel, the curvature of the surface did not play a significant ole in the distribution of flows. The position of this segment between the two extended sections of the valleys, and also a complex combination of forced bends, served as an additional factor in the concentration of flow in the narrow valley and the development of “areal erosion”, which led to significant material damage. A part of the city of Tulun is located in the spur of an adapted bend with fairly flat floodplain surfaces, which contributed to the spreading of the stream. The change of the downstream channel type from a broad-bottomed to an adapted one could provoke back water and retention within the urban area.