The object of the study is landslide activity on highways passing through the territory of the Karachay-Cherkess Republic. The paper presents the results of systematization and analysis of various sources containing information on the danger of landslide activation on the highways of the Karachay-Cherkess Republic for 2005–2023. The conditions and causes of landslide manifestations on the roads of the republic are characterized, the role of natural and man-made factors in the development of this process is determined. The maximum number of cases of landslide activation on the roads of the republic is timed to the spring-summer period and is mainly due to heavy precipitation. Over the past 19 years, more than 100 significant landslide occasions have been recorded, causing damage to highways passing through 10 administrative districts of the republic. In the period 2010–2023 alone, 6,816 km of roads were deformed (damaged, destroyed) by landslide processes, including 4,057 km of paved roads and 2,759 km of unpaved roads. Most of the road sections where landslide deformations occurred are located in the Karachayevsky and UstDzhegutinsky districts of the republic. A relatively high level of landslide activity on the roads of the republic was noted in 20162018. The volume of the most catastrophic landslide movements near highways sometimes reached 1–2 million m3. The sections of roads where landslide activations were periodically observed in different years have been identified. Information is provided on the location of landslide manifestations, activity, and the extent of deformations of the roadway in different regions of the republic. The analysis of the socio-economic consequences of the landslide activations allows us to conclude that they are quite dangerous for the automobile network in the territory of the Karachay-Cherkess Republic.

The object of the study was the hydromorphic soils of the Tashlyansky landscape of ravine forest-steppes, identified in the Stavropol Krai. The radial geochemical structure of differentiation of gross contents of Zn, Cu, Pb and Cd in the profile of meadow-chernozem soils formed under the influence of constant ground and seasonal surface moistening was studied. The features of lateral geochemi relation to the general lateral structure of migration of chemical elements, characteristic of the laid landscape-geochemical mesocatena within the Tashlyansky landscape, were also studied. The main methods were field and office analyses, analysis of scientific information on similar landscape-geochemical processes. The morphological characteristics and a number of physicochemical properties of meadow-chernozem soils have been established, which indicate the formation of differentiation in the soil profile by alkaline-acid conditions (there is a change from the neutral reaction of the environment in the humus horizon to a slightly alkaline one in the lower part of the soil profile) and oxidation-reduction conditions (there is a change from the oxidizing environment to a reducing gley environment). The radial differentiation structure of the total contents of Zn and Cu corresponds to the surface-accumulative distribution, which, together with the established statistically significant correlation coefficients with the humus content, indicates the fixation of Zn and Cu on the biogeochemical barrier as part of organomineral compounds. The radial differentiation structure of Pb and Cd is characterized by eluvial-illuvial distribution. The established correlation coefficients indirectly confirm the fixation of Pb and Cd as part of aluminosilicate clay minerals. Important phases-carriers of microelements in hydromorphic soils are oxides (hydroxides) of Fe and Mn, carbonates, easily soluble salts, which are visually determined in their profile. In the general picture of lateral differentiation of microelements along the landscape-geochemical mesocatena, meadow-chernozem soils act as low-contrast concentrators of Zn and Cu. More intensive radial migration of Pb and Cd from humus horizons in hydromorphic conditions affects the features of their lateral distribution along the landscape-geochemical mesocatena.

The article studies geozoological characteristics of the mountain rivers of the Kuban River basin within the borders of the KarachayCherkess Republic. The water availability of the Karachay-Cherkess Republic stands out from other southern regions of the Russian Federation with a significantly wide network of rivers. There are 419 rivers flowing through the territory of the republic, belonging to two basins: the Azov-Black Sea and the Caspian, and there are also over 130 lakes. All the rivers of the Azov-Black Sea basin are tributaries of various orders of the Kuban River. The largest tributaries of the first order are the rivers: Teberda, Maly Zelenchuk and Bolshoy Zelenchuk, Urup, Laba [4]. Currently, the rivers of the Kuban River basin are well-studied water bodies, however, due to the considerable length of the rivers, their upper reaches have been poorly studied. This is due to the fact that most ichthyological studies are aimed at studying the transformation of the ichthyofauna and the food supply, in connection with the construction of hydraulic structures: reservoirs, canals, hydroelectric power plants, etc. or studying the reduction of populations of sturgeon fish, due to the lack of migration routes. The purpose of this study is to study the ichthyofauna, food supply and habitat of the Upper Kuban and the upper reaches of the tributary river. The object of the study is the hydrobionts of the mountain rivers of the Karachay-Cherkess Republic. During the hydrobiological field research, generally accepted research methods were used. The identification of the fish species was carried out according to the appropriate determinants (Atlas, 2003; Berg, 1948-1949; Kuznetsov, 1973; Veselov, 1977; Kottelat, Freyhof, 2007, etc.), according to the modern classification (Reshetnikov et al., 1997; Reshetnikov et al, 2003; Shakhmurzov et al, 2012; Kottelat, Freyhof, 2007). The collection of aquatic invertebrates was carried out using generally accepted hydrobiological methods (Lipin, 1950; Martynov, 1952; Lepneva, 1968; Lukin, 1976; Fomin, 2000; Tsalolikhin, 1994–2004, etc.). The main result of the work was the compilation of geozoological characteristics of the ichthyofauna of the upper reaches of the Kuban River. Studies of the rivers of the upper reaches of the Kuban River confirm that the ichthyofauna is represented almost exclusively by brook trout.

The article studies the countries of the Sudan-Sahel region and the processes of terrorism development on its territory. At the country level, an attempt is being made to study terrorist activity and the factors that cause it. The time frame of the study is the entire period of the independent existence of the countries of the region, dating back to the early 1960s. A number of socio-political problems and contradictions that form the current political instability and geostrategic significance of the Sudan-Sahel region have been identified. The paper examines in detail the influence of a group of ethnodemographic factors on terrorist activity. Their main aspects are the dynamics and type of reproduction of the population, the structure and features of settlement systems, the ethnic composition of the population and its mosaic. In addition, the genesis and development of socio-political conflicts in the countries of the Sahel region, determined by these factors, were analyzed. Based on the collected statistical data provided by the number of terrorist acts and their victims on terrorist activities in the countries of the Sudan-Sahel region, the article examines the dynamics of terrorism in the region, highlights the periods of its development, identifies the spatial and temporal shifts and changes that have occurred. The current place of the region in the global trends in the development of terrorism is determined, the leading countries, terrorist organizations and hotbeds of conflict affecting terrorism in the Sahel are identified. As part of the study of regional features of terrorist activity, using the cartographic method and spatial and temporal analysis tools, specific territorial centers of terrorism were identified, as well as terrorist clusters  – Chad, Central, Eastern, Coastal, Tuareg, Darfur and South Sudan.

The object of the study is coagulation processes in clouds, which are a complex thermo-hydrodynamic and microphysical system characterized by unsteadiness, three-dimensionality and nonlinearity. These features make numerical modeling the main method of studying the evolution of clouds both in natural conditions and under active influence, which increases the requirements for the effectiveness of the numerical methods used, such as stability, convergence and cost-effectiveness. The development or selection of methods that meet these requirements necessitates careful research, including preliminary testing of these methods by comparing the results of calculations of test problems with their exact solutions. The study is based on the analysis of Cauchy test problems for kinetic (integrodifferential) equations and systems of kinetic (integrodifferential) coagulation equations in single-phase and two-phase spatially homogeneous dispersed systems. In the course of the work, it was found that the numerical solutions obtained using the Bubnov-Galerkin method and the developed iterative matrix method, which is a modification of the finite difference method, are in good agreement with the analytical solutions. These methods have demonstrated their applicability for modeling coagulation processes in mixed dispersed systems, including convective (hail) clouds. The high accuracy of the results of the numerical solution of the test problem related to coagulation processes in a dispersed medium, based on the results of the study, allows us to conclude that the Bubnov-Galerkin method and the iterative matrix method can be used to study microphysical processes in convective clouds. Numerical experiments based on these methods open up prospects for modeling the processes of cloud formation and development both in natural conditions and under active exposure, including drawing on the experience gained in previous research by other specialists in the field.

Heat is an unfavorable weather phenomenon, as it poses a serious threat to many sectors of the national economy: agriculture, energy, construction, etc. In addition, heat is a meteorological factor, significantly worsening the well-being of weather-sensitive people, people with cardiovascular and other diseases [1, 6]. Thus, the study of the climatic regime of heat is an important aspect in organizing various spheres of human activity. The information base for the analysis of the spatial and temporal distribution of hot days in the region was the observation data of 16 meteorological stations of the Stavropol Krai for 1971–2024, data from the Handbook of the USSR Climate [10] and the monograph Stavropol Krai: Modern Climatic Conditions [3]. The research was carried out using the methods of physical-statistical and regression analysis. For all meteorological stations of the Stavropol Region, the averaged main characteristics of the hot regime for the first 24 years of the new century are calculated: the annual, seasonal and monthly number of hot days and their total duration in the indicated periods. The extreme values of the specified characteristics are determined. The analysis of the annual course of the main characteristics of heat has been carried out. Based on the results of a comparative analysis of the obtained data with data for different long-term periods of the 20th century, a characteristic is given of the dominant trend in long-term changes in the frequency and duration of heat. It is shown that the distribution of hot days in the Stavropol Krai correlates quite well with its landscape structure [12]. In the semi-desert and dry steppe zones of the Krai, about 80 hot days are recorded annually, in the steppe zone of the territory — 60–70 days, in the forest-steppe — 40–55 days, in the mid-mountain zone — about 10 days. On average, about 30 days with extreme heat are observed per year in semi-desert and dry steppe landscapes, about 20 days in steppe, about 10 days in forest-steppe landscapes, about 5 days in the low-mountain zone, and extremely rarely in the mid-mountain zone. Heat as a dangerous phenomenon is recorded throughout the territory of the Krai, except for the low-mountain and mid-mountain zones. Throughout the territory of the Krai, the following is clearly visible: an increase in the annual and summer number of hot and very hot days; an increase in the frequency of heat of the level of a dangerous phenomenon; an increase in the frequency of long periods of heat.

With the growing interest in hard-to-recover hydrocarbon reserves, there is a need to increase the detail and quality of modeling the rock mass and reservoir formation. Taking into account the mechanical anisotropy of the medium, in particular caused by the layering of thin layers, provides a more complete picture of the stress-strain state of both the reservoir formation itself and barriers / bridges, which in turn opens up additional opportunities for optimizing the processes of field development, increasing the efficiency of hydraulic fracturing, as well as drilling wells. The technology of conducting laboratory studies of core material to study the anisotropy of elastic properties is described in the present study. Based on the results, the correlations for the elastic characteristics of rocks of the Sortym, Bazhenov and Abalak formations were obtained. Using the example of one of the deposits in Western Siberia, the results of constructing two types of hemechanical models (isotropic and anisotropic) are demonstrated. With the reference to comparison of values of the minimum horizontal stress and the absorption onset gradient, it is shown that the anisotropy of elastic properties has a significant effect on the stress-strain state of the rock mass. The use of isotropic models for anisotropic media leads to a significant underestimation of horizontal stresses / gradients of the onset of absorption, which, in turn, does not allow to unlock the potential of hydraulic fracturing, as well as to choose the optimal depth range for casing descent, which is critically important when drilling wells under conditions of AHFP. The obtained dependences can be used as a priori information in constructing geomechanical models of these objects in Western Siberia.

The need for separation of oil production, liquid and injection arises at fields where two or more formations are combined into one production facility. Correct allocation of production and injection is necessary for localization of residual reserves and assignment of geological and technical measures aimed at their development. The occurrence of errors at the stage of allocation of production and injection leads to uncertainty in localization of residual reserves, which causes low efficiency of geological and technical measures. For this reason, improving the technique for production and injection allocation in commingled production is an urgent task. The materials used for the study were publications in national and foreign scientific and technical sources related to the separation of production and injection, as well as field data and the results of interpretation of field geophysical studies. In order to improve the technique of separation of production and injection, based on the studied national and foreign experience in solving this problem, the most significant factors to be taken into account in the allocation technique were identified. The study proposes an improved technique for allocation of oil, liquid production and injection during joint development of two formations with account of changes in reservoir pressure, perforation intervals, reservoir productivity, propagation of hydraulic fracturing cracks, as well as different nature of formation flooding. The improved technique has been tested at one of the fields in Western Siberia, where two oil reservoirs have been combined for commingled production. The allocation of oil, liquid production and injection in each well for the entire development period has been performed, the development of reserves by reservoirs has been determined, and the presence of unproductive injection in the area of the technique testing has been established.