Volga Upland Research Articles

Contact zone of European (Meles meles Linnaeus, 1758) and Asian (M. leucurus Hodgson, 1847) badgers (Mustelidae, Mammalia) in the rightand left-bank districts of the Saratov region

DNA studies of badgers (Meles sp.) from the right-bank and left-bank areas of the Volga river in the Saratov region are described. Asian badgers (Meles leucurus Hodgson, 1847) inhabit the Left Volga Bank of the Saratov region, while European badgers (M. meles Linnaeus, 1758) inhabit the Right Volga Bank districts of the region, but Asian badgers were found in Khvalynsky district of the Saratov region, besides the European badger. Despite a sufficient number of publications devoted to the Asiatic badger distribution in the Vyatka–Kama region and the Volga region, and studies devoted to the development of systematics of the genus Meles in Russia, the question of the boundaries of the ranges of European and Asiatic badgers and the zones of their sympatry (parapatry) in the Volga–Kama region has not been fully investigated to date. Our work is devoted to the study of this question. As a result of analyzing the biological material collected by us, it was found that all five studied individuals of badgers from the Saratov Volga region phenotypically looked like Asian badgers, but our DNA analysis showed that only two of them were M. leucurus, whilst three ones were heterozygous individuals carrying genes from both species and were identified as hybrids. The remaining 29 individuals were captured in the right-bank areas of the region. Badgers were sampled from individuals from the northern to southern borders of the region in areas located along the Volga river on the Volga upland and in the Oka–Don plain. Of these, one individual from Khvalynsky district turned out to be an Asian badger, one individual from Krasnoarmeysky district was a hybrid of the two named species, and three individuals, one from Tatishchevsky, the second from Volsky and the third from Khvalynsky districts showed introgression of Asian badger genes into the genotype of the European badger. Thus, we have managed to find out that at this stage of development of the phase of the climatic cycle in the Lower Volga region, characterized by warming winters, the Volga river, with its two reservoirs within the Saratov region, is not an absolute zoogeographical boundary, and badgers, whose species are characterized by winter sleep, can in certain conditions overcome, most likely on ice, both the river itself and the lake parts of the Volgograd and Saratov reservoirs. According to the revealed introgression in some individuals from different areas on the Volga upland of the right bank of the Saratov region, it can be assumed that such traveling across the Volga river took place earlier, possibly before its flow was regulated by dams.

Pre-Mongolian Medieval Nomadic Monuments from the Saratov Region

The purpose of the article is to compile an up-to-date summary of the medieval nomad monuments dating back to the pre-Mongol period on the territory of the Saratov region. The following tasks are solved: cultural and chronological attribution of the complexes; their mapping; generalization and analysis of the data obtained in the context of the history of the Eastern European nomads. Various methods were used in the work: diachronic (periodization of the nomads existence in the studied territory), historical-systemic (study of nomadic society as a system) and historical-comparative (identification of general developmental patterns of nomadic societies), typological (typology and classification of the archaeological materials and complexes), and chronological (study of gradual development of the nomadic culture in the Lower Volga region). The main source of the study is the materials and publications on the nomadic archaeological sites from the Saratov region, as well as previous generalizing works on this topic. Data on 74 monuments are analyzed and mapped. The complexes are grouped into three natural and geographical zones (the basin of the Khopyor and Medveditsa rivers; the Volga Upland; and the Steppe Trans-Volga region). The complexes are also classified according to the three conditional chronological horizons: Saltovo-Mayaki (8th – 9th centuries); Oghuz-Pechenegs (9th – 11th centuries); and Polovtsian (late 11th – early 13th centuries). An attempt is made to correlate the well-known complexes of the Saltovo-Mayaki culture with its separate ethno-cultural groups (the Bulgars, the Khazars, and the Alans) and among the materials of the 9th –11th centuries to single out the Pecheneg and Oghuz components. The Polovtsian sculptures and the burials were correlated with written data on the groups of nomads from the Volga-Don steppes dating back to the middle of the 9th – early 13th centuries.

Cultivated plants and their wild relatives of Central Russia and the North Caucasus (results of a collecting mission of 2023)

In 2023, field explorations of cultivated plants and their wild relatives were carried out in the regions of the Volga Upland, the western part of the Caspian Lowland and the Stavropol Upland with the aim of further replenishing seed and herbarium collections of VIR.A total of 525 samples of CWR and cultivated plants were collected, including 200 are herbarium sheets, 323 seed samples of cultivated plants and CWR, and a couple of cuttings. The collected material encompasses 145 species, including 91 cultivars. Seeds of the cultivars were purchased at markets, in supermarket chains and from local residents. The following areas were examined in detail: the left bank of the Lower Volga (Peschany anabranch, Kigach anabranch, as well as the “Novaya Roshcha” protected area). In the Republic of Ingushetia the team collected samples of cherry plum, Caucasian pear, barberry, viburnum, Lonicera orientalis, sea buckthorn, raspberry, and Malus orientalis, which local residents use in their diet. Also, samples of spicy herbs such as savory, catnip, oregano, thyme, etc. were collected. Hops were sampled in the Tambov and Volgograd provinces, the Republics of Ingushetia, North Ossetia and Adygea, from abandoned household plots in Botanika village in Gulkevichi District (Krasnodar Territory). The exploration in vicinities of Derbent and of the wall of Naryn-Kala fortress in Derbent resulted in collecting a rare specimen of Secale sylvestre Host., which previously used to be a fairly common plant in the North Caucasus, but is very rare now. Vegetable crops were collected along the entire route of the collecting mission. It was not always possible to collect seeds, so a part of the material enriched the herbarium collection. The collected material reflects the use of a vast range of vegetable and spicy plant species by the local population.Collecting missions help to understand which species are of primary importance for the conservation of natural processes, biodiversity and the maintenance of local ecosystems. The genetic diversity of a region is a key object of research for geneticists and plant breeders. Landraces of vegetable, cereal and other crops may have unique properties, such as adaptation to local climate conditions or disease resistance. Work on the mobilization and conservation of the plant genetic diversity is the basis for modern breeding and genetic research.

Identification of Surface-Carbonate Soils and Soils with Variegated Underlying Rocks in the South of Volga Upland on Satellite Images

Identification of Surface-Carbonate Soils and Soils with Variegated Underlying Rocks in the South of Volga Upland on Satellite Images

Сопоставление эффективности использования современных геодезических методов в изучении последствий бобровой деятельности на малых реках

Multiple increase in the beaver population on the East European Plain has led to the appearance of a large number of beaver dams and ponds on small rivers. At present, the problem of regulating small rivers in this region remains poorly studied due to the above circumstances. This study presents the results of a comparison of modern geodetic methods obtained using an electronic total station, GNSS equipment and UAVs. The small river Morkvashinka, flowing along the northern tip of the Volga Upland, was chosen as the object of the study. The spatial coordinates and altitudes measured by the GNSS receiver generally agree well with the tacheometric survey data. The height difference is 0.5 cm (standard deviation – 0.07). However, the main disadvantage of an electronic total station, which limits its use for surveying linearly elongated objects and small river valleys, is the lack of direct visibility of the objects being photographed from the device due to the highly dissected territory, the tortuosity of the river and dense vegetation. Using orthophoto and digital terrain models obtained from unmanned aerial vehicles, it is not always possible to accurately determine the border of the coastline, as well as the absolute heights of the dam, floodplain, terraces, water edge, channel marks (pond depth) due to dense vegetation. However, the river bed and floodplain, beaver dams and ponds are clearly visible on them.

Fauna and biotopic distribution of Chrysomelidae (Coleoptera) in the Shaitan-Tau State Nature Reserve, Russia

Research on taxonomically diverse groups of insects are an important component of studying biodiversity in Protected Areas of various ranks. Based on the results of original studies (2017–2020), this paper presents for the first time data on the Chrysomelidae family and its species composition in the Shaitan-Tau State Nature Reserve, Russia. The study area is located in the south of the forest-steppe zone of the low mountains of the Southern Urals in the Orenburg Region, Russia. Currently, this Chrysomelidae fauna is one of the most studied ones in Protected Areas of the Southern Urals. In the study area, 180 Chrysomelidae species have been registered, which is 51% of the Chrysomelidae family in the Orenburg Region. In addition, 86 recorded species were found for the first time in the Shaitan-Tau State Nature Reserve, including eight species recorded for the first time in the Orenburg Region. A new species of the genus Altica was discovered in the study area. In terms of the level of species richness, the Chrysomelidae family of the Shaitan-Tau Nature Reserve is comparable with or noticeably richer than other local faunas of the Protected Areas of the Southern Urals. At the same time, this Chrysomelidae fauna has fewer species than of other state nature reserves and national parks in the forest-steppe zone of the Volga Upland. Features of the zoogeographical structure of the Chrysomelidae family in the Shaitan-Tau State Nature Reserve include quite a high number of West-Palaearctic species (23 species; 12.8%), many of which are located there on the eastern limit of their natural ranges, and a low proportion of Central Palaearctic species (3.9%). At the same time, two Siberian species were discovered (Labidostomis sibirica and Gonioctena flavicornis), which are located on relict island sites of their ranges in the Urals. These findings noticably distinguish the studied fauna from the Chrysomelidae of the steppe Protected Areas in the south of the Orenburg Region, where a considerable proportion are representatives of the Kazakh-Turanian genesis. The studied Chrysomelidae fauna is characterised by a set of rich groups of steppe, meadow-steppe, nemoral and, to a lesser extent, boreal forms (a large part of which are located on the lomits of their ranges in the study area), as well as a pronounced spatial mosaic of biotopic complexes (e.g. forest, steppe, floodplains). In general, the data presented in this study objectively characterise the Chrysomelidae fauna of the Shaitan-Tau State Nature Reserve as a reference for the Ural oak forest-steppe ecosystem, which emphasises its important role for the conservation of natural complexes, as well as the knowledge of the current state and historical stages of the formation of biota of the western macroslope of the South Urals.

РАСЧЕТ ЗАПАСА УГЛЕРОДА В БИОМАССЕ ДРЕВОСТОЕВ ЗАЩИТНЫХ ЛЕСНЫХ НАСАЖДЕНИЙ ПО ГРУППАМ ВОЗРАСТА ПРЕОБЛАДАЮЩИХ ПОРОД

Increasing the productivity and efficiency of protective forest plantations, taking into account their impact on solving the carbon neutrality of regions, is an urgent problem of modern agroforestry science. Based on the importance of solving the problem of reducing the volume of carbon dioxide, the purpose of the research is to assess the net ecosystem exchange of carbon dioxide in protective forest plantations (HLN) in the forest-steppe zone of the Volga upland. The paper uses methods for calculating the regional estimate of the carbon budget. The formation of a functionally targeted "carbon fiber" system of WLD facilities is carried out using a systematic priority-target method based on the basic forestry classification of protective forest plantations by age groups and breed composition. The distribution of protective forest stands by age group and breed composition made it possible to calculate the carbon reserve in the biomass of stands of protective forest stands. The calculation of the biomass of stands of coniferous and hardwoods made it possible to identify and establish for each age group the potential ability to effectively deposit carbon in the soil. Based on the carbon reserves established for each age structure and rock composition in the biomass pool of coniferous and hard-leaved stands by soil and climatic subdistricts, it becomes possible to regulate the carbon balance at the level of a separate region, a separate forestry enterprise. Taking into account the agroecological conditions of the sites – objects of protective afforestation, their main purpose, it is possible to use ZLN to include them in the long-term target "carbon" system of the region, with the development of measures for the regime of their use and increase their protective functions.. The accumulation of biomass of stands of different age groups depends on the soil and climatic disparity of slopes of different exposures and different agro-climatic subdistricts. Losses of carbon reserves in pools of protective forest plantations due to external influences as a result of economic activity or lack of care for these plantations reduce their protective effectiveness and productivity. Carbon reserves in the biomass of a stand of coniferous and hardwoods depend on their age structure.

On the weevil fauna (Coleoptera, Curculionidae) of the Volga upland and the Oka-Don lowland

Information is provided on new ndings in European Russia of 14 rare species of weevils (Curculionidae), signi cantly complementing the knowledge of their distributions. Icaris sparganii pertinax , Ceutorhynchus nanus , Platypteronyx auritus , Platygasteronyx solskyi , Pseudorchestes asiaticus and Phacephorus hirtellus were recorded for the rst time on the Volga Upland ( Phacephorus hirtellus was reliably recorded for the rst time in the fauna of Europe). Ceutorhynchus nanus , Oprohinus suturalis , Tychius pumilus , Orchestes quedenfeldtii and Pseudorchestes exiguus are discovered for the rst time in the Oka-Don Lowland. Eight species are listed for the rst time for Saratov Province, six species, for Voronezh Province, and one species for Volgograd Province. For some species, new data on their host plants have been obtained.

Recognition of Rocky, Sandy and Calcareous Soils from the Surface in the South of the Volga Upland (Volgograd Oblast) from Satellite Images

The purpose of the work is to recognize rocky, sandy and calcareous soils from the surface using a multi-zone satellite image in the south of the Volga Upland in the Volgograd oblast. The object of the study was the Volga-Don irrigation system, within the experimental station “Oroshayemaya”. The recognition was carried out by the spectral brightness of the space image of the bare soil surface in 4 bands. The most ranked values among them were marked in B1 band. Three catenae were studied, along which field information about soils was obtained. It was found that the greatest brightness (B1) is created by stones, rubble and sand scattered on the surface (970–1100 units). This is followed by: surface-effervescent soils with strongly rubbled rocks at a depth of about half a meter and sandy loam soils (710–830 units), with effervescence from the soil surface on mottled loams and sands of about half a meter (up to 700 units), and surface-calcareous soils, where mottled loams and sands occur deep (more than 70 cm), or with the absence of calcareous material in the surface horizons, with a brightness of 560–670 units. The use of this approach will enable more detailed recognition of soils on the basis of satellite imagery materials and separate surface-rocky and sandy soils from surface-calcareous soils, which are displayed in images with a similar spotty heterogeneity, but differ in spectral brightness.

Identification of Rocky, Sandy, and Surface-Calcareous Soils in the South of the Volga Upland (Volgograd Oblast) on Satellite Images

Identification of Rocky, Sandy, and Surface-Calcareous Soils in the South of the Volga Upland (Volgograd Oblast) on Satellite Images

Analysis of the Potential Range of Mountain Pine-Broadleaf Ecotone Forests and Its Changes under Moderate and Strong Climate Change in the 21st Century.

Climatic changes have a significant impact on the composition and distribution of forests, especially on ecotone ones. In the Southern Ural, pine-broadleaf ecotone forests were widespread during the early Holocene time, but now have persisted as relic plant communities. This study aimed to analyze the current potential range and to model changes in habitat suitability of relic pine-broadleaf ecotone forests of the suballiance Tilio-Pinenion under scenarios of moderate (RCP4.5) and strong (RCP8.5) climate change. For modelling, we used MaxEnt software with the predictors being climate variables from CHELSA Bioclim, the global digital soil mapping system SoilGrids and the digital elevation model. In the Southern and Middle Urals, climate change is expected to increase the areas with suitable habitat conditions of these forests by the middle of the 21st century and decrease them in the second half of the century. By the middle of the 21st century, the eastern range boundary of these forests will shift eastward due to the penetration of broad-leaved tree species into coniferous forests of the Southern Ural. In the second half of the century, on the contrary, it is expected that climate aridization will again shift the potential range border of these forests to the west due to their gradual replacement by hemiboreal coniferous forests. The relationship between the floristic composition of pine-broadleaf forests and habitat suitability was identified. In low and medium habitat suitability, pine-broadleaf forests contain more nemoral species characteristic of deciduous forests of the temperate zone, and can be replaced by broadleaf forests after thinning and removal of pine. In the Volga Upland, suitable habitats are occupied by pine-broadleaf forests of the vicariant suballiance Querco robori-Tilienion cordatae. Projected climatic changes will have a significant impact on these ecotone forests, which remained completely unaltered for a long time.

Monetary Valuation of Ecosystem Services Provided by Protective Forest Plantations in the Agroforestry System in the South of the Volga Upland

The purpose of the study is an economic assessment of the effectiveness of agroforestry based on determining the value of ecosystem services of an afforested model land object and extrapolating the data obtained to the territory of the south of the Volga upland with identical natural and economic conditions to the model. The study presents a methodology for the economic assessment of ecosystem goods and services of forested agricultural landscapes based on the modern classification of ecosystem services: CICES. It is established that the economic value of the regional ecosystem product provided by forested lands in the dry steppe is USD 1323 per 1 ha of agroforest landscape per year (price for 2021 on average for 30 years). Of these, regulatory and maintenance services account for 52% of the total economic value, security services—45%, and cultural services—3%. The projected economic value of ecosystem services that will be provided by afforested lands in the south of the Volga upland, the price for 2025, taking into account inflation, is estimated at almost USD 20 million. This value is a sufficient justification for conducting forest reclamation works in the region and providing recommendations for their necessity for small enterprises and farms.

Динамика экосистем свежего бора центра Приволжской возвышенности

The results of a study of the dynamics of a rather rare type of forest ecosystem for the central part of the Volga Upland – fresh pinery (A2) – are presented. The research was carried out on the territory of the Upper Sura section of the Volga Forest-Steppe Nature Reserve. The progress of the process was studied in an age series, identified in homogeneous forest conditions based on the principles of dynamic classification of forest types. As a result of processing forest taxation data, average values of taxation indicators of forest stands were obtained for each age class. At the same time, an analysis of changes in all components of the plantings was carried out. On its basis, the age series was divided into separate periods and phases. Trends in the share of participation of each forest-forming species in the forest stand at different age stages are described by nonlinear equations. The study showed that the resulting age series represents a series of transformation of forest communities. Disruption of the forest formation process led to a large-scale replacement of indigenous plantings with derivatives. After the start of clear-cutting, the area occupied by deciduous trees (primarily birch) constantly grew. A consequence of the large-scale use of intermediate, sanitary and voluntary selective fellings was the formation of thinned pine stands. At the same time, a transformation of the lower tiers of communities also occurred. These factors caused a deterioration in the conditions for natural regeneration of pine (Pinus sylvestris L.). As a result, to date, the possibility of forming pine stands through natural regeneration is almost completely excluded.

Development of Meta-Geosystems of Tourist and Recreational Clusters

The study aims to find a key to the problem of managing cultural heritage systems in the example of the Temnikov-Sanaksar cluster located in Eastern Europe. This area is situated between the forest-steppe of the layered-tier Volga upland and the forest geosystems of the layered Oka-Don lowland. The article applies an interdisciplinary approach to solving the problem of optimizing inter-component relationships in the meta-geosystems of tourist and recreational clusters. The sustainable development of meta-geosystems should be based on multifactorial information support, which implements the most important condition for the effective economic development of landscapes through the formation of the regions’ spatial data infrastructure. In order to consistently optimize meta-geosystems of different hierarchical levels, it is necessary to solve several emerging issues, such as assessing the strength and nature of inter-component connections in geosystems, determination of factors describing the territorial variation of the properties of geosystems, interpreting and substantiation the semantics of the selected basic factors.

Channel Gradient as a Factor in the Distribution of Beaver Dams and Ponds on Small Rivers: A Case Study in the Northern Extremity of the Volga Upland, the East European Plain

A very noticeable increase in the beaver population (mainly the Eurasian beaver (Castor fiber L.)) in the East European Plain since the end of the 20th century through reintroduction contributed to the emergence of a large number of beaver dams and ponds, which resulted in the transformation of the channels and the hydrological regime of small rivers. In this paper, for the first time in the Middle Volga region, regularities in the distribution of beaver dams and ponds on small rivers were revealed based on a topographic survey of the river channel, regulated by beaver activity in recent decades. The materials of the paper were obtained during field (geodetic) work in August and September of 2022 in the valleys of two small rivers typical for the north of the Volga Upland, Morkváshinka River (16.6 km) and Morkváshka River (7.8 km), with subsequent statistical processing. According to the results obtained, all the dams we encountered were located in the sections of their channels with relatively small (up to 1%) and medium (1–3%) average gradients. In the upper reaches of the rivers, the expansion of beaver activity is limited to the large gradients of their channels. Along the entire length, there is an alternation of sectors with a “natural” (not regulated by beavers) channel and a cascade of beaver ponds. Drained (at the time of the survey) sectors without dams, as well as those with preserved and destroyed dams, were also identified on the Morkváshinka River. On the whole, 26–48% of the length of the studied rivers has been transformed by beaver activity. The average number of dams per kilometer of the watercourse is 3.7–5.1. The most favorable channel gradients for beaver activity are 3.6–16.6 m/km, or 0.36–1.66%. The average gradient of the channel, above which no beaver dams and related ponds were found in these rivers, is 30 m/km, or 3%. An increase in the channel gradient upstream of the rivers is reflected in the size of beaver dams and ponds. The beaver dams and ponds are slightly larger in the sections of the rivers with a relatively small average gradient than in the sections with a medium average gradient of the channel.

Medieval Perevoloka and the Construction of the Volga-Don Shipping Canal under Peter the Great

The ancient Cossack portages through the Volga upland — perevoloka — were the main transport communications between the Volga and the Don in the 16th–17th centuries in the area of their maximum convergence. Repeated attempts to construct the Volga-Don shipping canal along one of these portages were made in the Middle Ages but were crowned with success only in Soviet times. This issue has not been sufficiently studied in the scholarhsip. Researchers have written about three old Cossack portages: Kamyshinskii, Dubovskii, and Tsaritsynskii. Practically nothing is known about the Sarpin portage. As a result of the conducted research, the authors of the article come to the conclusion that originally the are between the Volga and the Don was called perevoloka, which was limited to the mouths of the Don rivers — Tsaritsa and Panshinka — and the Volga rivers — Mechetka and Sarpa. It was here that Turkish soldiers in the 16th century tried to build a canal. At the beginning of the 17th century, after the construction of the Tsaritsyn fortress at the mouth of the Tsaritsa river, the Don Cossacks mastered the Kamyshinskii-Ilovlinskii portage, making it the main one and thereby expanding the territory of the portage. Through this portage, Peter the Great made a second attempt to establish the Volga-Don canal between the rivers Kamyshinka and Ilovlia, for which, in order to protect the future waterway between the Volga and the Don, he built the Tsaritsyn line on the perevoloka.

Establishing the regularity of the impact of protective forest plantations and relief on agrophysical and biochemical properties of soils in the Volga uplands

Establishing the regularity of the impact of protective forest plantations and relief on agrophysical and biochemical properties of soils in the Volga uplands

Landscape structure of the territory of the sanctuary Bakhteevskie Uvaly (The Volga Upland, Russia)

A map of the landscape structure of the territory of the state nature sanctuary of regional significance Bakhteevskie Uvaly is presented. The research area is located in the eastern part of The Volga Upland in the landscape zone of the steppe (the northern steppe subzone). The vegetation cover and flora of the Bakhteevsky Uvaly nature sanctuary, despite the high anthropogenic pressure on the natural ecosystems of the Starokulatkinsky district, have preserved high floral and phytocenotic biodiversity, and rare, endemic and relict species have been preserved on the territory of the protected area, reference steppe and forest communities. That is why the nature sanctuary Bakhteevskie Uvaly was organized here. Taking into account the landscape features of the territory is necessary both for the rational organization of economic activity and for the implementation of environmental protection and scientific goals. The research based on the results of field work, carried out in 2021, remote sensing data, thematic maps and literary sources. Spatial data processing is performed using QGIS. As a result of the research the landscape structure of the territory was established, the degree of anthropogenic disturbance of landscapes and the main threatening factors within the researched area were established.

ВЛИЯНИЕ ЭРОЗИОННО-РУСЛОВЫХ СИСТЕМ НА ИНФРАСТРУКТУРУ НАСЕЛЕННЫХ ПУНКТОВ ЕВРОПЕЙСКОЙ ЧАСТИ РОССИИ

The infrastructure of any settlement, whether it is a village or an urban agglomeration, ensures the functioning of the systems that serve the needs of the population. Regardless of the age of the settlement, its size and layout, the system of engineering communications depends on the features of the relief and erosion-channel processes in this area. To identify the impact of gully erosion and riverbed processes on the functioning of infrastructure, the southern megaslope of the Russian Plain was selected. There is a high degree of erosive dissection and activity of riverbed processes. Satellite images and cartographic material were used to assess the impact of erosion-channel processes. For the basins of the Volga, Oka, Don, and Dnieper rivers (within the territory of the Russian Federation), a map of the impact of erosion-channel processes on the infrastructure of settlements has been compiled. The basis for drawing up the map was a physical and geographical map of Russia on a scale of 1:8,000,000 and a map of the hazardousness of channel processes on the rivers of Russia. The resulting map shows 120 settlements: 84 – in the Volga River basin, 13 – in the Don River basin, and 24 – in the Dnieper River basin (within the Russian Federation). According to the developed methodology, each settlement was assigned a score of the impact of erosion and riverbed processes on the infrastructure. The most common are small values of such impact: 1 point – 45%, 2 points – 29.5%, 3 points – 23%, 4 points – 2.5% (only 3 settlements). The lowest (1–2 points) impact on the infrastructure corresponds to the territories within the lowlands and relicts of glacial relief. Settlements on the Central Russian and Volga Uplands are more dependent on gully erosion (3–5 points) and show a weak dependence on riverbed processes. The research results indicate an ambiguous impact of erosion and riverbed processes on the infrastructure of the settlements. Large and big cities are less dependent on erosion and riverbed processes, in contrast to small and medium-sized ones.

Morphometric characteristics of lake bottoms of Lakes CHarskoe and Nuksenskoe (Volga upland, Russia) as the basis of their classification

The article presents the results of researching the morphometric and hydrological characteristics of Lakes CHarskoe and Nuksenskoe and suggests their genesis. Lakes have scientific (zoological, botanical, geological, geomorphological), water conservation significance, perform the environmental function of typical biocenoses of karst lakes. During the research, a bathymetric survey was carried out from the board of a boat, using an echo sounder, combined with a navigator. The results of field research were processed using the geoinformation program QGIS, digital models of the relief of lake basins were constructed, the main morphometric and hydrological characteristics were calculated. Based on the analysis of the morphometric characteristics of lakes and data on the landscape features of their surroundings, primarily on the geological structure (geostructural, lithological, etc.), conclusions are drawn about the karst origin of lake basins and the classification of lakes according to a set of criteria is carried out.