Visnyk of V. N. Karazin Kharkiv National University, series "Geology. Geography. Ecology"

Tectonic inversion of the Dnipro-Donets basin. Part 3. Tectonic style of deformations

Oleksii Bartaschuk Bartaschuk , Vasyl Suyarko, Oleksandr Chuienko — Thu, 01 Jun 2023 00:00:00 +0000

The purpose. The peculiarities of the spatial distribution and tectonic style of collisional deformations of the riftogenic structure of the Dnipro-Donets Basin were investigated.

Method. Kinematic and paragenetic analyses were used, structural drawings were studied, kinematic models of alpine-type deformations in the folded floors of the southeastern segment of the Basin were compiled.

The results. It was found that the riftogenic structure along the strike different style and intensity of inversion complications was been undergone. The structural border between the weakly and significantly located territory along the meridian of the city of Balaklia was determined. To the west of the border the rift downthrows acquired arc-shaped contours and a pendulum structure due to horizontal movements. Zones of Hercynian folding are divided into separate branches by echelon systems of landslides located diagonally to their axes. To the east of the border, at first the regional board faults bend to the west, and then to the east of the city of Donetsk, the northern ones bend to the east, and the southern ones - to the southeast. The zones of nearboard and axial regional faults are destroyed, and because of this, the lines of the Kochubiyivsko-Volvenkivskyi and Sosnivsko-Stepkivskyi axial salt dome shafts are interrupted. The relic is the Axial fault with the Druzhkiv-Komyshuva shaft adapted to it. Instead of a reset rift, a shear-thrust inversion frame of orocline form was formed. Alpinotype dislocations on most of the territory of the Basin are weakly pronounced (scattered, low-amplitude faults and uplifts), but the southeastern segment significant fault-folding and cover-thrust deformations has undergone. The analysis of the structure of the Oligocene-Miocene sediments shows that neotectonic structures in the sole of the Cenozoic cover and the daytime relief are reflected. On the northern board of the Basin, a number of arc-like elongated uplands that located in the hanging wings of the Hercynian thrusts were formed. A sign of uplands` formation in the geodynamic environment of transpression is oscillating articulation and diagonal placement relative to shear-thrust zones.

Scientific novelty. By the analysis of structural pictures of Elements of tectonics characteristic of transpression zones was identified. For the first time the nature of alpine-type deformations on kinematic models was identified. The Cenozoic movements along the re-mobilized zones of the Hercynian thrusts formed dynamically coupled ensembles of neotectonic structures was established. The hinged-jointed structural parageneses were formed by the mechanism of longitudinal elongation of the geological space due to the horizontal movements of right kinematics over the zones of dynamic influence of shear-thrusts of the foundation. It was found the tectonic style of the latest deformation ensembles is inherent in the platform fold-thrust geostructures of the tectonic breakaway. For the first time the newest platform structure - the West-Donetsk tectonic orocline of cover-folding deformations was identified.

Practical significance. Data on the distribution of alpine-type complications of the West-Donets Graben for paleogeodynamic reconstructions and improvement of the regional scheme of tectonic zoning of the Dnipro-Donetsk Basin can be used.

The model of the oil and gas system of the Devonian sedimentary complex of the Biloliskyy block of the Dobrudja foredeep

Volodymyr Hnidets, Kostyantyn Hryhorchuk, Lesia Koshil, Myroslava Yakovenko — Thu, 01 Jun 2023 00:00:00 +0000

The purpose of the article is to find out the main principal features of the ontogenesis of the oil and gas system of the Devonian deposits of the Dobrudja Foredeep.

Methods and methodology - generalization of data on the lithology of Devonian deposits, analysis of materials on the development of paragenic facies associations in evaporite basins, construction of a principled model of the hydrodynamics of the Dobrudja basin on this basis and predicting the distribution of various lithogenetic types in the Devonian period. Historical-catagenetic reconstructions were carried out on the basis of the provisions of the fluid-dynamic concept of catagenesis.

Results. On the basis of the reconstruction of the dynamics of the sea basin and the nature of the lithofacies zonation, the conditions of Middle-Late Devonian sedimentation were modeled. A wider development of sediments enriched in organic matter, both in the section and laterally, is argued. First of all, this applies to the Middle Devonian deposits, which, together with the Lower Devonian black shale formations, formed the body of oil and gas formation centers, that were localized in the depocenters of the Tuzliv and Alibey depressions.

The Devonian sediments were affected by two major cycles of catagenesis, with active substages (so-called critical moments) associated with large-scale fluid migration. The time of manifestation of the active substage of the first cycle (Middle-Late Carboniferous) was the main one in the migration of hydrocarbons, which is associated with a sufficiently high degree of post-diagenesis of the generating strata: gradation of catagenesis MK₅ (Lower Devonian), MK₃ - MK₄ (Eifelian). Hydrocarbons moved through the zones of regional decompaction, which were developed at three hypsometric levels. In this case, flows of hydrocarbons of different phase composition were formed. The source of the gas was the Lower Devonian deposits, and the main volume of oil was generated in the Eifelian layers. During the second cycle of catagenesis, due to a decrease in reservoir temperatures and a significant depletion of the potential of organic matter, only processes of reformation of previously formed hydrocarbon deposits are predicted. Due to the fact that the generation centers were confined to deposits of different ages, differed in temperature regime, ways of fluid migration, and were separated from each other, there are reasons to assume the existence of three oil and gas systems.

Scientific novelty and practical significance. For the first time, a wider spatial and age range of development of oil and gas source strata, localized centers of generation, discrete paths and time of large-scale migration of hydrocarbons have been scientifically substantiated. The studies carried out provide good grounds for predicting the possibility of the formation of large volumes of hydrocarbons that could be accumulated in the Devonian deposits of the Dobrudja Foredeep.

Anomalous position of Paleozoic faults of Western Donbas

Sergey Goryainov, Ihor Udalov — Thu, 01 Jun 2023 00:00:00 +0000

Statement of the general problem. The oil and gas-bearing province of Eastern Ukraine is located in the Dnipro-Donetsk Basin (DDB). It covers the Paleozoic structural floor and is buried under younger sediments. The Paleozoic structural floor of the territory is represented as a long rift graben. The maximum thickness of the sedimentary cover in the graben is 15–17 km. According to geophysical data, the thickness of the earth's crust is 31–32 km under the axial part of the DDB and increases towards the sides. But according to the maximum thickness and facies characteristics of the Paleozoic deposits, the thickness of the Earth's crust below them could not exceed 20 km. The modern thickness is 1.5 times higher. Therefore, such a geological-geophysical model of the structure of the DDB is contradictory.

Analysis of recent research and publications. The removal of the contradiction is possible due to the detection of a series of Hercynian thrusts with total amplitude of thrusts of the order of 50 km. Such thrusts began to be established on the northern and southern flanks of the DDB. Hercynian thrusts have a southwestern vergence. In the north, the Voronezh crystalline massif is pushed onto the DDB along the Noviy thrust with an amplitude of 9–10 km. In the south, the South Donbas melange zone is established, which pushes the folded Donbas onto the Ukrainian shield. On its continuation to the northwest is the southern side of the DDB - the so-called Southern monocline. The well-studied Pavlograd-Petropavlovsk coal mining district of Western Donbass with operating coal mines is located within its borders.

An unsolved part of the overall problem. Numerous faults with relatively small amplitudes are established within the Paleozoic Southern Monocline. Together, they form a system of horsts and grabens with a north-western extension. But the bottom parts of the grabens are 1–3 km higher than the tops of the horsts. Such a geological situation is anomalous. This indicates the post-fault dislocation of the horst-graben system as a whole.

The purpose of the article is identification of the causes of the anomalous structural position of the graben-horst system in the modern geological structure of the Southern Monocline and in the general model of the geological structure of Eastern Ukraine.

Research materials and methods. Were involved more than 390 geological sections, constructed based on the data of more than 10,000 wells. Of them, 265 wells revealed the folds that are being analyzed. In addition, were used data of catagenetic transformations of the sedimentary section.

Presentation of the main research material. The South Donbas mélange zone falls to the northeast and continues under the Southern Monocline. It is located in the upper block of this regional thrust structure and is in an allochthonous setting. According to geological data, the true amplitude of the thrust of Western Donbas on the Ukrainian shield is 15–20 km, and the vertical component of this amplitude exceeds 3 km. Such spatial parameters explain the abnormality of the structural position of the horsts and grabens of Western Donbass - their southwestern flanks were significantly raised relative to the northeastern flanks during thrusting.

Scientific novelty. Therefore, in the modern geological structure, the Dnipro-Donetsk "basin" is not a rift, but a post-rift Hercynian folded region. It is formed by high-amplitude thrusts on the northern and southern flanks. The Hercynian fold region is buried under Mesozoic and Cenozoic sediments and is further complicated by Laramian and Attic fold-thrust dislocations of lesser intensity.

Conclusions. The thrust model brings the geophysical parameters into the correspondence with the geological data and is confirmed by the actual material.

Regeneration of deposits of hydrocarbon fields of Ukraine

Yaroslav Lazaruk — Thu, 01 Jun 2023 00:00:00 +0000

Formulation of the problem. In the world's oil and gas-bearing basins, there are known examples of an increase in the reserves of hydrocarbon deposits as a result of inflow of fluids from the deep subsoil. Recently, the theory of the Earth degassing is gaining popularity. There are more and more arguments in favor of the fact that in many oil- and gas-bearing provinces of the world, oil and gas deposits are constantly replenished due to the migration of hydrocarbons through degassing pipes. Certain prospects for maintaining oil and gas production are possible as a result of the natural recovery of depleted deposits in Ukraine as well. However, this issue has not been sufficiently studied and requires further research.

The purpose of the article is to argue with actual materials for the regeneration of hydrocarbon deposits, to estimate the probable volumes of their replenishment, to determine the methods of geological research to outline the zones of nourishment of hydrocarbon deposits.

Materials and methods. Research materials are actual materials from the development and permanent assessment of hydrocarbon reserves of Ukrainian deposits. The research methodology consists in the analysis of the facts of the replenishment of hydrocarbon deposits from the point of view of new scientific concepts of the supply of hydrocarbons from the deep subsoil.

Results. Based on the results of the increase in reservoir pressures of spent gas condensate deposits and repeated calculations of hydrocarbon reserves of the Shebelynka, Chornukhy, Bilousivka and Proletarka deposits of the Dnipro-Donets Basin, a conclusion was made about the replenishment of deposits due to the vertical migration of oil and gas, the probable scales of deposit regeneration were estimated. The results of industrial development of the East Kazantyp and North Bulganak gas fields of the Indolo-Kuban depression also testify to their probable feeding from the depths. Adiabatic fracture formation associated with seismotectonic impulses and phenomena of natural rupture of rocks by deep fluids plays a significant role in the formation of unconventional deposits. The result of fluid fracturing of rocks is specific matrix microcracking. It is well manifested in well cores from depths of more than 5.5 km (Semyrenky, Machushy deposits of the Dnipro-Donets Basin). Hydrocarbon deposits at these depths have a zonal character and are not controlled by the structural factor.

Scientific novelty, practical significance and recommendations. Actual materials have proven that some hydrocarbon deposits in Ukraine are constantly being replenished as a result of seepage of deep fluids. It is likely that the main channels of hydrocarbon supply to deposits are deep faults. To determine the degassing channels it is advisable to use the methods of field geophysics and geochemical studies. We can state that the replenishment of gas reserves of some Dnipro-Donets Basin fields according to confirmed facts ranges from 14 to 1800 million m³ annually. It is necessary to monitor the spent deposits, therefore it is advisable not to liquidate decommissioned wells, but to preserve them or transfer to the fund of observation wells, periodically measuring reservoir pressures and determining the character of fluid saturation of spent deposits. It is necessary to manage the process of extraction of hydrocarbons, applying a policy of balanced economical production.

Jurassic system stratigraphy at the Kamianka village. Part 1. The Kozhulinska formation

Andriy Matveev, Marianna Pakki, Olena Shevchuk, Oleksandr Klevcov — Thu, 01 Jun 2023 00:00:00 +0000

Introduction. Despite the active research of Jurassic system deposits of Donbas during the last two centuries the issue of their stratigraphy principles is still debatable. The authors` analysis of the available scientific material revealed a conflict between the normatively established requirement to rely on lithostratigraphy during the sediment research, and the fact that the existing common system relies on biostratigraphy. This contradiction could be solved by the study of lithostratigraphic units of the Donetsk Jurassic deposits. Therefore, the purpose of the article was to research the Kozhulinska formation, establish its composition and describe its main features. The Lower Jurassic deposits from the outcrops near the village of Kamyanka (Izyum district) were studied, since the studyable stratotypes of most of the Jurassic strata, which are well exposed in the studied area, are available in this area.

Material and methods. The scientific search was based on the analysis of literature, results of previous drilling and mapping works, as well as own field, laboratory and analytical studies. Clay samples were taken from different stratigraphic levels of the formation and from different lithological varieties. Laboratory research was carried out in two directions: using an electron microscope and a spectrometer to detect the material composition of clays. A palynological analysis of these deposits was also carried out, namely, stratified deposits with the help of microphytofossils, including, for the first time, according to the orthostratigraphic group – dinocysts.

Results and discussion. The results showed that the Kozhulinska formation was mainly represented by shaly clays (gray, dark gray, sometimes blue-gray) that contained relatively thin layers of sandstones. The main mass of clays consisted of hydromicas, with an insignificant content of montmorillonite, and an even smaller amount of kaolin. The layers of quartz sandstones cemented with clay material were separately traced along the strike.

Paleontological remains in the clays of Kozhulinska formation were rare. Palynological groups are mainly represented by pollen and spores, as well as remains of dinophytes, green algae and acritarchs. According to paleoalgological analysis, the sediments of the Kozhulinska formation are dated for the first time.

Stratigraphy. Kozhulinska formation is represented by a fairly uniform layer of montmorillonite clays of hydromica composition. The clays are mainly siltstone, but there are, especially in the lower part, washed clean varieties. It is impossible to divide the formation into sub formation based on lithological features. According to biostratigraphic data, deposits are divided into Plinsbachian, Toarian and Aalenian.

Paleogeography. At the end of the Early Jurassic and the beginning of the Middle Jurassic era, the territory of the Kamianska area was a low-lying part of the seabed that was drained during low tides. The land that surrounded it was also low-lying and almost did not supply detrital material, however, there is a regular removal of plant detritus. The source of the terrigenous material was the sedimentary complexes of the Donetsk Ridge. Features of the chemical composition of the world are a significant amount of iron (siderite, ocher, chamosite) and the absence of calcium and magnesium carbonates. At the end of the early Aalene, this unstable basin finally regresses, which leads to the accumulation of a powerful subaerial pack of sandstones, which weigh and border the cores of anticlines - elevated areas of the bottom or small islands.

Assessment of groundwater vulnerability within the cross-border areas of Ukraine and Poland

Halyna Medvid, Luibov Yanush, Tatiana Solovey, Dmytro Panov, Vasyl Harasymchuk — Thu, 01 Jun 2023 00:00:00 +0000

Problem statement. The growing global trend of groundwater consumption and excessive groundwater abstraction in many parts of the world requires an accurate and comprehensive assessment of the potential for groundwater resource development. The EU-WATERRES international project has begun developing a concept for coordinated management and harmonized monitoring of groundwater resources in the transboundary areas of Ukraine and Poland. Studying groundwater's natural protection status or vulnerability is a priority, as groundwater pollution has become a significant environmental problem in recent decades due to the growth of industrial production and agricultural activities.

Study objective is to analyze the existing materials on the natural protection of groundwater within the study area and to quantify the vulnerability of the main useful aquifer (MUA) to surface pollution in the cross-border Polish-Ukrainian area.

Methodology involves the quantitative method of groundwater vulnerability assessment by calculating the time of pollutant penetration into the aquifer through the aeration zone using the modified Bindemann formula and GIS.

Research results. Studies have shown that the most vulnerable among MUA there is an unconfined alluvial Quaternary horizon (alQ) of the Syan and Dniester River basins. Throughout its entire development, its vulnerability corresponds to the "very high" category because of pollution from the surface caused by precipitation filtration. The Upper Cretaceous aquifer (K2) is less vulnerable. The groundwater of this horizon in the Polish part of the cross-border area is more vulnerable - here the vulnerability corresponds to the categories "very high" and "high". In the Ukrainian part, the Upper Cretaceous aquifer is characterized by better natural hydrogeological conditions and is less vulnerable to pollution. The Lower Neogene aquifer, which has a limited distribution on the slopes of the Western Bug-Syan River watershed within Roztochia, is the least vulnerable to pollution as compared to the others. The lithological composition of the aeration zone and the thickness of weakly permeable and practically impermeable rocks have a decisive impact on the filtration time and vulnerability of groundwater to pollutants from the surface by infiltration.

Scientific novelty of the research. For the first time, a quantitative assessment of the vulnerability of the MUAs for the Polish-Ukrainian cross-border area was carried out. The use of the results of this assessment will facilitate the adoption of appropriate management decisions for the comprehensive protection of transboundary groundwater, prevention of its pollution, and reduction of anthropogenic impact.

Improvement of the description of ostracods of the family TRACHYLEBERIDINAE

Vitalii Syniehubka — Thu, 01 Jun 2023 00:00:00 +0000

Introduction. The definition of criteria for separating closely related species of representatives of the genus Cythereis is currently incomplete. Ostracods of this genus have wide intraspecific variability and high adaptability to changing living conditions. These factors make it difficult to use these ostracod species for regional stratigraphic correlation. In addition to the selection of criteria for species separation, there is a problem of the imperfection of the terminological apparatus for describing ostracods, which complicates the description of species and omits potentially important information for the separation of related species.

Analysis of previous publications. Numerous works are devoted to the issue of the development of the terminological apparatus for describing ostracods, however, qualitative methods of description are inherent only to certain large taxa, where a separate method of description has been developed for each taxon. Ostracods of the genus Cythereis are widespread in the Cretaceous Tethys. Their wide variability is considered by various authors often without taking into account intraspecific variability and adaptation, which leads to the selection of subspecies or ignoring variability.

Materials and methods. Numerous ostracods of the species Cythereis hirsuta Damotte&Grosdidier from the Late Cenomanian and Cythereis ornatissima (Reuss) from the Turonian of Ukraine were used in the work. Ostracods were selected from different deposits according to the conditions of origin.

Results and discussion. The paper describes in detail the morphology of ostracods of the genus Cythereis with qualitative characteristics of morphological elements. The ontogenetic changes of the two species and the change in morphology depending on the conditions of existence are also described. The change in the morphology of juvenile forms depending on the conditions of existence is described separately.

Conclusions. Based on the study and description of numerous paleontological materials, a number of refinements were proposed to the descriptive characteristics of the morphological elements of ostracod valves of members of the family TRACHYLEBERIDINAE Sylvester-Bradley, 1948 and the genus Cythereis in particular. The proposed clarifications regarding the morphology of the mesosculpture made it possible to describe in detail the ontogenetic changes of the studied species and their differences in adult stages depending on the facial conditions of existence. It should be noted that a detailed scheme for describing the morphology of mesosculpture is proposed for the first time in the literature. The paleontological description of numerous materials from the Middle Cretaceous of Ukraine allowed to establish the morphological elements that are of primary importance for the separation of related species within the genus. The analysis of these elements suggests that some of the similar species from the outcrops of Europe and Asia are actually other species. The question of their phylogenetic ties can be solved under the condition of studying ontogenesis and expanding the geography of research. Based on this, the validity of the names of the studied species from the territory of Ukraine is also contradictory to the actual comparison with the holotype collection.

Integrating remote sensing and aeromagnetic data for lithological and structural lineaments mapping in Abu Ghaylan - Kiklah - Tighrinna, northwest Libya

Nureddin Saadi , Ousama Elkoul, Saleh A. Sadeg — Thu, 01 Jun 2023 00:00:00 +0000

Problems Statement and Purpose. Libya is the fourth-largest country in Africa and the seventeenth-largest country in the world with area of 1,759,540 sq. km. Most of Libya is located in the Sahara Desert and known for being the driest and most remote regions with limited accessibility. In the 1970s, the Industrial Research Center in Libya began to create geological maps of all Libyan lands derived from analog (hard-copy) aerial photographs and geological field trips to some accessible places. Recently, remote sensing and data integration techniques using GIS are crucial to geological survey and mapping, which provides a useful tool for studying and investigating the geology of remote regions without having to physically access them. The purpose of this study is mapping lithological unites and structural lineaments in the region of Abu Ghaylan - Kiklah - Tighrinna, northwest Libya, using integrated remote sensing data and spatial analysis.

Data and Methods. Enhanced Thematic Mapper Plus (ETM+), Satellite Pour l'Observation de la Terre (SPOT 5), European Remote-Sensing Satellite-2 (ERS-2) Synthetic Aperture Radar (SAR) C-band, Digital Elevation Model (DEM), geologic maps, and aeromagnetic data were used to map and analyze the lithological and structural lineaments in the study area. Various fused images and IHS transformations were tested for lithological units recognizing. On the basis of spectral characteristics and topographic forms, lithological and structural lineaments were recognized and mapped. The extracted rasters and vectors data were integrated using remote sensing and GIS data integration techniques.

Ground Truthing. The purpose of the ground truthing was to validate the DEM-based structural mapping and identify any landslides, streams, or valleys that may appear as edges in the DEM data. Also, determining the locations of the artificial lines, that appears in the processed images as geological lineaments and edges.

Results and Discussion. The results indicate that remote sensing data were very useful in distinguishing between various rock units and recognizing geological lineaments in the study area. The generated lithologic map shows fifteen geological formations with apparent and accurate boundaries. The results exposed new geological lineaments in the study area. The direction of the extracted geological lineaments is dominantly NW-SE. The magnetic data reveal the boundary of sedimentary basin in the study area. The basement's depth within the basin varies from 122 meters to 4.5 kilometers. The extracted geological lineaments were analyzed and interpreted to provide more information about the main structural trends affecting the study area. The methods used in this study for remote sensing image analysis and field geological surveys can be used successfully in similar regions of Libya.

The influence of dangerous geological and technogenic processes during engineering and geological research and environmental safety for construction in the modern period

Victor Sokolov, Valeriy Sukhov — Thu, 01 Jun 2023 00:00:00 +0000

Problems Statement and Purpose. Reliability of construction, protection of the territory from dangerous geological and technogenic processes, assessment of impact of construction and reconstruction objects on the environmental safety of the territory should be based on high-quality materials of engineering investigations. Today in Ukraine, the conditions of construction and reconstruction have significantly increased the requirements for the quality and composition of engineering research. At the same time, there are a number of natural and social factors that increase the degree of geotechnical and environmental risks during construction, there is no system that ensures the mandatory implementation of state regulations, which has an extremely negative effect on the quality of research materials. These questions are of particular importance given the volume of work that awaits us in the reconstruction of our country.

The purpose of article is to once again draw attention to the problems in the field of engineering and geological investigations for construction, which largely depend on the safety and comfort of our living, to formulate proposals for improving the state of affairs in anticipation of the large-scale recovery of our country and the possibility of entering the regulatory field of the EU.

Data & Methods. The legislative framework of Ukraine in the field of engineering and geological investigations for construction has been analyzed.

Results. The article provides an analysis of the state with the legislative base in Ukraine regarding engineering surveys, the system that ensures mandatory compliance with the requirements of regulatory documents, factors that increase man-made and environmental risks in construction, proposed measures aimed at improving the quality of survey materials. 4 factors have been established that systematically affect the quality of engineering and geological investigations and the safety of construction: 1) most accidents and deformations of buildings and structures are associated with processes in the "base - foundation" system; 2) about 80% of the territory of Ukraine is characterized by complex engineering and geological conditions, with manifestations of almost all dangerous geological processes: seismicity, karst, landslides, reworking of banks, subsidence, soil swelling, etc.; 3) a significant increase in the specific weight of construction in conditions of dense urban construction and reconstruction of existing buildings in the total volume of construction; 4) social and economic conditions. An example of a change in the qualitative characteristics of underground hydrosphere (chemical composition and increase in the aggressiveness of groundwater), which had an impact on the reliability of construction and the ecological component at the studied area, has been considered.

The Late Cretaceous marine basin of platform Ukraine (morphometry, stages of development, lithology and stratigraphy of sedimentary formations)

Leonid Yakushyn — Thu, 01 Jun 2023 00:00:00 +0000

Formulation of the problem. The relevance of the research is related to the formation of a holistic view of the Late Cretaceous Sea basin of the study area: its boundaries, area, the existence of probable land areas, conditions of sediment accumulation and historical development.

The purpose of the article. Based on the results of exploratory, structural-exploratory and parametric drilling conducted during the State Geological Survey on scales of 1:50,000, 1:100,000 and 1:200,000 and own field research, we supplemented the information on the geohistorical chronicle of the Late Cretaceous of the southwestern part of the SEE.

Methods. The material for writing the article was the results of drilling more than 10,000 exploration, structural and parametric drilling wells conducted during the State Geological Survey at scales of 1:50,000, 1:100,000 and 1:200,000, which are stored in the State Information Geological Fund of Ukraine.

Also, the results of own field research of 47 most complete open sections of the Upper Cretaceous of Platform Ukraine were taken into account and a significant literature on the geological structure of the studied area was processed.

Research methods: facies and formation analysis, lithological, petrographic, paleontological, litho-biostratigraphic, geophysical, etc.

At the final stage of the mapping of the Upper Cretaceous sediments of Platform Ukraine, the methodology of sedimentary basin monitoring and modeling of formation units was used with the help of the domestic software package "Geomapping" with further conversion to the ArcView grid format.

Results. To find out the spatio-temporal distribution of the Upper Cretaceous deposits of the study area, their composition, stratigraphic position and parameters of the Late Cretaceous sea basin, we analyzed the materials of mapping, structural search, exploratory and parametric drilling over the past 50 years were analyzed, our own studies of open sections of the Upper Cretaceous were taken into account, and significant stock material on the geological structure of the studied area was also processed. The most informative wells were selected as reference wells. Their number varied from 1179 for Early-Middle Cenomanian deposits to 1103 for Turonian deposits. The maximum density of the studied sections of support wells was recorded for the territory of Volyn-Podillia and individual blocks of the Ukrainian Shield (USH) and is 23.1 wells per 1000 km2, the minimum - in the water areas of the Ukrainian part of the Black and Azov Seas - about eight per 1000 km2. The absence of Upper Cretaceous deposits on a significant territory of platform Ukraine was established. Early-Middle Cenomanian and Turonian deposits have the largest distribution area, and Maastrichtian deposits have the smallest. In our opinion, areas with continental conditions of existence in certain ages or during the entire Late Cretaceous period have been identified. This made it possible to calculate the areas of land areas and areas covered by the sea with the help of software, with a certain percentage of error (up to 10%). The area of the sea basin was up to 80% of the territory of platform Ukraine. In the historical development of the Late Cretaceous Sea basin of the study area, two stages are distinguished: early-Middle Cenomanian and late Cenomanian-Maastrichtian, which differed significantly from each other in terms of hydrological, hydrochemical, temperature regimes and the nature of sedimentation. The lithological characteristics of the deposits according to the modern stratigraphic division of the Upper Cretaceous rock complex are given.

Territorial transformations in agriculture of Chernihiv region in the context of climate change: the case of corn and sunflower

Mykola Baranovskyi, Denys Hlushko — Thu, 01 Jun 2023 00:00:00 +0000

Introduction. Different crops and regions of Ukraine are characterized by unequal dependencies on climate change. This situation creates a demand for scientific research to analyse «climate-agricultural production» dependence at the regional level. Chernihiv region, whose territory is located in two environmental zones, is an ideal testing ground for assessing territorial transformations in agricultural production under the influence of climate change.

The purpose of article. The purpose of the study was to identify territorial transformations in agricultural production of Chernihiv region that were formed under the influence of climate change during 2001-2020, using corn and sunflower as an example. Additionally, the impact of climate factors on the yield of the selected crops in the region was assessed.

Research methods. The study was based on data on gross harvest and yields of the selected crops, corn and sunflower, in Chernihiv region during 2001-2020. Climate trends were represented by average air temperature and precipitation during the growing season for the same period. Spatial transformations of the region’s agricultural production were determined using the territorial concentration index. A number of calculations were carried out to assess the contribution of climatic factors to the dynamics of yields of the selected crops. They included the determination of 1) trend yields; 2) total and agrotechnical variance; 3) the share of the climatic factor in the total variance.

Main findings. In 2001-2020, Chernihiv region observed a significant increase in heat supply, the length of the growing season, and the sum of effective temperatures. The climate trends of this period created suitable conditions for expanding of a number of heat-tolerant crops, including corn and sunflower, into the region. The study used them as selected crops to assess territorial transformations in agricultural production of this northern region of Ukraine. The analysis of statistical data showed that the sown area and gross harvest of corn and sunflower increased tenfold in Chernihiv region, and the local agroclimatic zones of their cultivation moved 125-150 km north.

The main producers of corn and sunflower are still the forest-steppe areas of the region. At the same time, its Polissya part currently produces 25 to 30% of the gross harvest of these crops. Due to climate change in the region, the yield of the selected crops has increased significantly, exceeding the national average values by 37-43%. The «migration» of heat-tolerant crops to the region has considerably changed the specialization of agricultural production in this Polissya region. Based on the calculations, it was found that the contribution of the climatic factor to corn yields was maximum in 2001-2010 - 74%. The contribution of climatic trends to sunflower yield of the region was significantly lower - 53-56 % in different periods. Taking into account the results obtained, the study points out the need to develop effective measures for adapting agricultural production in Chernihiv region to climate change.

Scientific novelty and practical value.

The article describes for the first time the characteristics of territorial transformations in agricultural production of Chernihiv region in the context of climate change and assesses the contribution of the climatic factor to the dynamics of productivity of the selected crops in the region. The practical value of the study is the possibility of using its algorithm to conduct similar studies in other regions of Ukraine. The results of the study are important in the context of substantiating regional measures to adapt agricultural production to climate change.

Periodization of the formation of garden and park landscapes of the Central Europe

Hryhoriy Denysyk, Iryna Kravtsova — Thu, 01 Jun 2023 00:00:00 +0000

Formulation of the problem. During of his activities, man sought to harmonize the territory that surrounded him. The environment had to perform not only utilitarian functions, but also aesthetic ones, to satisfy the needs of man in the contemplation of the «beautiful». This aspiration led to the formation and development of a special group of man-made landscapes – garden and park landscapes. Garden and park landscapes are the «smart» group of man-made landscapes, which constructively combines natural components with components formed as a result of economic, art human activity.

The aim of the work. To develop and substantiate the periodization of the formation of garden and park landscapes of Central Europe for their detailed knowledge and rational development.

The research methods. The performed periodization is based on two main research principles: historical and on the principle of natural-anthropogenic coexistence. General scientific and specific scientific research methods have been used.

Presentation of the main research material. In the history of formation and functioning of garden and park landscapes of Central Europe it is necessary to distinguish the following periods: sacral; regular, in the structure of which the following directions are singled out and justified: residential, sacral-regular, and proper regular; landscape with romantic and realistic directions; constructive and eclectic. Each of these periods is characterized by the dominance in the structure of the landscape of natural or anthropogenic component, regular or landscape style of organization of the landscape, has a different level of transformation of the natural basis, a certain functional load, different owners. The landscape structure is formed by the corresponding types and subtypes of garden and park landscapes, which change according to the selected periods. The article shows the change in the genetic structure of garden and park landscapes in accordance with reasonable periods and directions of formation and development. Garden and park landscapes of Central Europe were organized within the channel, floodplain, floodplain-terrace, slope and watershed types of areas, the landscape structure of which was formed by the corresponding types and subtypes of man-made landscapes, represented by park plantings, regular gardens, ponds, canals, paths, stairs, palace, outbuildings, sculpture, garden furniture, etc. It is established that garden and park landscapes performed various functions, namely: economic, aesthetic, sacred, memorial, medical, are places of short-term rest and material manifestation of power and spirituality of owners.

Assessment of the volume of provision of cultural ecosystem services by Kyiv green zones

Nataliia Korohoda, Tetiana Kupach — Thu, 01 Jun 2023 00:00:00 +0000

Among the groups of ecosystem services, cultural ecosystem services (CES) are the most in demand in cities. Currently, the status of the CES evaluation remains problematic.

Accordingly, the purpose of the work was to develop the provisions of the methodology for estimating the volumes of the most demanded CES and determining the value of green areas in providing CES, taking into account the demand for them.

Methodologically, the work consisted in the steps: 1) identification of indicators of the effectiveness of the provision of CES, which are of decisive importance when citizens choose green areas to visit, which is an aspect of the CES offer (residents' perception of green areas; the character of their use; value and suitability to perform recreational and wellness functions; indicators defining restrictions on the use of green areas, etc.) 2) Normalization of calculated indicators based on a single scale, to determine the total volume of the CES offer: was applied the one-sided increasing Harrington desirability function. 3) Development of a methodology for the entire CES calculation. According to the general algorithm, the evaluation was based on the sequential determination of the potential of the green zone in providing CES, as an average value of the indicators of perception of the territory and of the total CES offer - the number of CES that the green zone is able to provide, taking into account the value of CES restrictions.

As a result of calculations according to the algorithm, an assessment of the volume of CES of was estimated in the selected 14 green zones of the city Kyiv. The calculation showed that none of the selected green zones provide the maximum volumes of CES, only 3 of them have higher than average volumes, 9 have average volumes, and 1 green zone each has minimum and lower than average volumes. At the same time, the potential of the researched green zones for the provision of CES: the maximum volumes in 2 zones and in the absolute majority - 11 is higher than the average volume. Accordingly, in almost all green zones there is a lack of receipt (loss) of significant amounts of CES, mainly due to the presence of problems that lead to a deterioration of the perception of green zones by residents.

In order to determine the consumer value of green zones the indicator of alternative availability of green zones was used, which reflects the ratio of supply of ES and demand for them. Among those investigated in the work, 2 green zones were identified, which due to low supply in areas with high demand for CES, should receive maximum attention when making priority management decisions.

Thus, the research solved the scientific task of objectively taking into account in the CES evaluation all aspects that determine the CES offer. This method, in combination with the determination of the value of green areas in providing CES, can be used in urban planning practice as a tool for improving the quality of urban green areas, their sustainable development and providing citizens with the maximum amount of CES.

Integrative role of human geography in solving global problems of modernity

Thu, 01 Jun 2023 00:00:00 +0000

The purpose of this article is to substantiate the integrative role of human geography based on the information-synergistic paradigm and UN materials on sustainable development in solving global problems of the 21st century.

Results. The analysis of previous studies and the relevance of the chosen research topic indicate the high place of geography in general and human geography in particular. Such an analysis indicates of the importance of the raised topic and the integrative role of human geography in the leading universities of the world, which determines its important worldview, mental and cultural role in society. It can ensure the survival of the contemporary civilization of our planet and ensure the right for future generations to live and evolve in favorable conditions of the biosphere. More and more scholars are advocating the importance of geography as an integrative discipline and a leader in providing education for sustainable development. The article presents the integrative role of human geography in solving the global problems of present, namely the interaction in the system "Human - Society - Nature". The article provides a thorough analysis of the main UN documents on the implementation of the strategy of sustainable development in the life activity of society and the education system. Human-geographical science and education are considered from the standpoint of the tasks of post-non-classical science of the 21st century. The article describes the formation of the foundations of education for sustainable development, which should be anticipatory in nature, widespread in various regions of the planet with the support of all countries of the world. The article defines the essence of post-non-classical science, the role of individual sciences in solving the global problems of present and the place of human geography in it. The concept of the information revolution of the contemporary world, the role of sciences in it, in particular information geography, is justified. The article provides a detailed overview of the development of human geography in the leading universities of the world and Ukraine and analyzes the their research areas. The analysis of educational problems of human geography in Ukraine and V. N. Karazin Kharkiv National University was carried out. An analysis was conducted to reveal the features of the structure, content, methods and methodology of human geography in the leading countries of the world, Ukraine and at our university. The article states that the main trends of the world's leading universities regarding the development, place and role of humam geography as a complex science of human, society, and nature are powerfully implemented in our university. It is also stated that human geography has a powerful meaning, because it should contribute through its research and educational programs to the formation of the foundations of a global mentality, the basic conditions of global culture in particular. Based on the conducted research, the article presents the main points of development of human geography, in particular in Ukraine, to ensure its integrative role in plans for the future development of the planet in terms of the sustainable development requirements.

Taking into account the modern demand for the integration of scientific research and the necessary changes in the education system, this study reveals the role of human geography as an integrative science and education in accordance with the requirements of sustainable development and overcoming global problems of civilization.

Industrial tourism as an effective direction of urban regeneration (analysis of Kryvyi Rih practice)

Viktoriia Patsiuk, Volodymyr Kazakov — Thu, 01 Jun 2023 00:00:00 +0000

Formulation of the problem. The world is constantly moving towards the post-industrial phase of development of society, and if the majority of civilized Western countries have decided on their place and role, the cities of Ukraine are just beginning to outline their future landmarks. This is especially true for the future of single-industry cities, the number of which in Ukraine is quite large. Kryvyi Rih is the largest city with exclusively industrial specialization, performing administrative functions only at the local level and having a scientific sector almost completely focused on the needs of the industrial complex. For the last 10 years, managers and scientists have been actively thinking about the problem of diversifying the city's economy and changing its image, and this is reflected in the Marketing Strategy for the city development. Industrial tourism is one of the key tasks of the Strategy. The promising character of the chosen direction of activities is confirmed by the practice of European countries, which are guidelines for development for us. This is due to the fact that not only individual cities, but also entire regions of Great Britain, Germany, France, Poland, the Czech Republic have a wide experience in regeneration of former industrial territories and further popularization of successful practices through industrial tourism.

Methods. The research is based on the system approach and the dialectical method of cognition. The key scientific results are obtained using a complex of general scientific methods, namely: analysis and synthesis, abstraction, theoretical generalization. The historical method enables determining significant moments for development of this tourist destination. With the help of these methods, industrial tourism is considered in its internal and external relations entirety. The simulation method enables presenting the organizational model of this tourist destination at the local level. Comparative-geographical and statistical analysis methods allow assessment of the state and dynamics of tourism development in Kryvorizhzhia (Kryvyi Rih region). Based on the method of observation and analysis, the most visited objects of industrial tourism in Kryvyi Rih are systematized and their base map is created.

The study aims to analyze best practices of implementing theoretical developments concerning establishment of industrial tourism in Kryvorizhzhia so that Ukrainian cities with similar resources can factor in all positive areas and minimize shortcomings.

Results. The theoretical foundations of industrial tourism establishment are analyzed and this definition is outlined. The practice of Kryvyi Rih concerning integrated development of industrial tourism as a direction of further regeneration of the city, which is pioneering for our country, is revealed, the results obtained are analyzed and available shortcomings are identified.

Scientific novelty and practical significance. An organizational model of industrial tourism has been developed, which demonstrates the relationship between the resource of the territory and the management mechanism for introducing tourist activities in order to create a tourist product and bring it to the tourist.

The climate change impact on greenhouse gas emissions (CO2 and N2O) from soils at agroecosystems

Anatoly Polevoy, Alexander Mykytiuk, Lyudmila Bozhko, Elena Barsukova — Thu, 01 Jun 2023 00:00:00 +0000

Formulation of the problem. Soils are a significant source of greenhouse gases (GHGs), the release of which into the atmosphere forms the global warming potential. Mathematical models describing greenhouse gas emissions make it possible to assess the impact of climate change on the GHG emissions on a regional scale, and study how land-use changes affect these emissions.

The study is aimed at assessment of potential changes in CO₂ and N₂O emissions from soils at agroecosystems under the influence of temperature regime changes and increasing aridity in the context of global climate change.

Materials and methods. Numerical experiments with a comprehensive model of GHG emissions from the soils at the winter wheat agroecosystem were performed by means of RCP4.5 climate change scenario. The study is based on the materials of agrometeorological observations at the hydrometeorological station of Bilovodsk (Eastern Ukraine) for the period of 1991-2020 and the climate change scenario RCP4.5 for the period of 2021-2050.

Results. Classification of crop vegetation conditions allowed us to reduce the diversity of their regimes to certain weather types, characterizing the common conditions of crop formation in spring and summer, due to which the so-called ‘dry’ and ‘humid’ years were distinguished. The tendencies of change in air temperature and rainfall during vegetation of winter wheat in years different on humidity have been established. The increase in air temperature from the beginning of the growing season was gradual, while maintaining a stable correlation: a ten-day average long-term temperature was more than a temperature of the ‘dry’ year which was more than a temperature of the ‘humid’ year.

The intensity of greenhouse gas emissions is defined by the type of humidification in the growing season. In the ‘dry’ years at the beginning of the vegetation season, CO₂ emissions will make up 0.044-0.079 tons of С-CO₂ ha^-1 per a ten-day period, which is higher than the average long-term values and almost twice as high as in the ‘humid’ years.

In the spring at the beginning of the growing season, as a rule, the level of moisture content in the arable soil layer is quite high, which leads to the formation of anaerobic conditions. They, in turn, determine the level of N₂O emissions. Increasing aridity reduces the level of N₂O fluxes. For ‘dry’ years, at the expense of a fairly high level of spring moisture of the arable layer at the beginning of the growing season, the level of N₂O emissions was quite high (0.061-0.089 kg of N-N₂O ha^-1 per a ten-day period). Subsequently its level decreased significantly.

In general, total greenhouse gas emissions in terms of CO₂ equivalent will decrease by 6.2% in ‘dry’ years and by 32.3% in ‘humid’ years.

Conclusions. Based on numerical experiments with the model of greenhouse gas emissions from soils at the winter wheat agroecosystem, the general patterns of vegetation-related variation of CO₂ and N₂O emissions are identified. The main patterns feature consists in increasing CO₂ emissions during spring-summer vegetation of winter wheat from the beginning of a growing season to the wax ripeness phase and in decreasing N₂O emissions from the beginning of the winter wheat growing season until its ending. Their peculiarities are defined by the years’ different humid conditions.

The modern nature of changes in the average monthly air temperature during 2006-2020

Svitlana Pyasetska, Oleksandr Shcheglov — Thu, 01 Jun 2023 00:00:00 +0000

The proposed article is devoted to the study and analysis of changes in the field of average monthly air temperature on the territory of Ukraine over the past fifteen years (2006-2020) of the period 1991-2020 to determine the trends that have emerged as a result of changes in global circulation over the Atlantic-European sector of the Northern Hemisphere and the possible occurrence of frequent drought events on the territory of Ukraine. Тaking into account the drastic climate changes that have occurred during the last decades, there is a problem in adapting a number of branches of the production complex to such changes in order to prevent economic losses and develop a new strategy in this direction.

Connection with research tasks. The presented study is related to the implementation of a number of state-ordered research works dedicated to the study of the peculiarities of modern climate changes in Ukraine and the identification of climate-vulnerable areas on its territory.

Problems to be solved in the article. Taking into account the accumulated material regarding the features of the distribution of the air temperature field in Ukraine and the probabilistic scenarios for its change under the influence of general warming in the Northern Hemisphere, for the territory of Ukraine it is necessary to find out the mechanism of its current changes and determine their direction on a temporal and territorial scale.

The main purpose of the presented article was to investigate and establish the main trends in the current field of average monthly air temperature in Ukraine over the past 15 years (2006-2020) and show the nature of the spatial and temporal distribution of these changes.

Materials and methods. The data of the average monthly air temperature at 55 stations of Ukraine during all months of the year for the fifteen-year periods 1991-2005 and 2006-2020 served as the research materials. The main research methods were physical and statistical to determine the deviations of two 15-year periods and cartographic to determine spatio-temporal differentiation of detected cells.

Main results. It was established that on the territory of Ukraine in January 2006-2020 there was a certain decrease in the average monthly air temperature due to lower temperatures. In the rest of the winter months, its growth is observed, especially in the territory of the northwestern, northern, and northeastern regions and in some central and southern regions.. In the spring, the increase in the average monthly air temperature in 2006-2020 occurred more intensively in the northern regions and in a number of regions of the western region (Peredkarpattia). In the summer, the increase in air temperature was observed throughout the territory of Ukraine, but most intensively in July. Territorially, the greatest increase in the average monthly air temperature was expressed in the north, northeast and south. In autumn, the increase in the average monthly air temperature was most intense in November 2006-2020 in the regions of the northern and central regions, as well as in the Carpathian region.

In the last 15 years, the average monthly air temperature in Ukraine has increased, but in January it decreased in the north, northeast, in some places in the center and south. This trend is new for today's climate.

The results of the study for the territory of Ukraine are presented for the first time and can be used for planning agricultural works.

Physical meaning of temperature and evaluation of distribution laws (in the area of the Lake Sevan basin)

Armen Sedrakyan, Varduhi Margaryan, Svitlana Reshetchenko , Sviatoslav Dmitriiev — Thu, 01 Jun 2023 00:00:00 +0000

Formulation of the problem. In the work, the most general definition of temperature was discussed and presented, the temporal probability distribution of air temperature was analyzed and evaluated. Temperature has no specific definition. Thus it will be difficult to study the nature of any geophysical phenomena, including the characteristics of temperature distribution, without understanding the modern scientific definition and adjustment of temperature.

The aim of the work is to give the most modern reasonable definition of temperature or what the thermometer measures, the answer to which requires a more specific scientific justification, as well as to evaluate the patterns of possible spatiotemporal distribution of air temperature in the territory of Armenia and in the area of the Lake Sevan basin.

Methods. To solve the set tasks, the authors used corresponding research and published works as a theoretical basis in the work.

In the work, the average monthly data of actual observations of the temperature of the ground surface air layer and the amount of precipitation of the «Center for Hydrometeorology and Monitoring» SNCO of the Ministry of Environment of the Republic of Armenia were used. It was found that temperature is a quantity characterizing the thermal state and radiation of the terrestrial and celestial bodies and, in general, the environment, which is strongly related to the entropy change of the system; temperature is the main thermodynamic characteristic of thermal equilibrium; the thermodynamic and microscopic concepts of temperature coincide; the temperature-heat (energy) difference becomes known in the sense that a system can have high energy but low temperature.

The authors applied the following research methods in the article: mathematical and statistical, extrapolation, analysis, analogy, correlation, cartographic.

Results. Energy depends on the geometry (dimensions) of the system, but temperature does not. A trend of increasing air temperature is observed in the RA territory, which is also a result of the entropy change of the system. It can change very quickly, depending on the environmental factors in the given area (the growth rate of greenhouse farms, the artificial filling of valleys, which are wave carriers of air flow, the relentless use of green spaces for the purpose of public buildings, and other factors) in the process of disrupting the excessively permissible norms, which are currently separate needs serious research and prevention.

The long-term variability of surface air temperature in the area of the Lake Sevan basin is analyzed. The analysis carried out made it possible to give a quantitative assessment characterizing the climate change in this region over the past 98 years. An analysis of the observational data showed that the trend of climate warming is confirmed by an increase in air temperature both in winter and over a long period of time. The change in surface air temperature occurs at a rate of 0.002 ºС/year to 0.012 ºС/year and is generally 0.008 ºС/year (or 0.08 ºС/10 years) for all analyzed stations. The results obtained confirm the presence of two periods of warming observed in 1927–1970 and 1971–2021. All the results obtained in the course of the work testify to the trend of climate mitigation in the area of the Lake Sevan basin at the end of the 20th - beginning of the 21st century.

Towards urbanistic geosituation delineation

Denys Serohin, Sergiy Kostrikov — Thu, 01 Jun 2023 00:00:00 +0000

Introduction. Modern cities are complex and rapidly expanding systems. For their more effective study, it is necessary to use methods of urban remote sensing, in particular, LiDAR survey. Processed LiDAR survey data, visualized in a 3D scene, model a certain urban configuration that represents a static picture of the relationships between objects, processes and phenomena in the urban environment. The representation of such configurations in the dynamic plane are urbanistic geosituations.

The main research objective of the paper is to define the concept and present the essence of the urbanistic geosituation.

Results. The urbanistic geosituation is a dynamic aspect of a certain state of the urban environment, in which there are objects, processes and phenomena that are in dialectical unity with this urban environment. The urbanistic geosituation can be represented as a separate area of the urban environment in a certain research context with a specific state that is currently not inherent in other areas.

The article describes in detail the property of the structural heredity of geosituations, which can be traced during the growth of cities. New buildings and roads are laid out taking into account the existing layout, thus inheriting the structure of the original geosituations.

On the example of the city of Washington using 2D and 3D maps, the article discusses the features of identifying inherited urbanistic geosituations using the general functionality of visual analysis. On the example of the city of Kharkiv are described urban problems that arise as a result of unplanned development and ignoring the structural heredity of urbanistic geosituations.

Repeating geosituations with common properties and internal configurations are combined into different rank geosituational patterns, which are tracked on city maps with the naked eye. The higher the rank of the pattern, the more stable it is, and the larger territories it covers in terms of more generalized properties. The formation of geosituations patterns is successfully combined with the feature of collecting and storing LiDAR data, which are divided into many areas of the same size – tiles.

An important property of urbanistic geosituations is their variability, which manifests itself in the city study in the context of the daily population concentration. Diverse internal urban processes and phenomena often lead to the emergence of urbanistic geosituations that characterize the temporary gravity centers of the population.

To search, identify and analyze urbanistic geosituations, it is necessary to use two key components – global coverage maps and geographic information systems (GIS). The article describes a special web-GIS that combines these components and provides an environment for exploring urbanistic geosituations in a 3D scene. Three use-cases are also proposed for analyzing urban systems at the geosituational level: visibility analysis, buildings energy consumption estimation, and population estimation [11, 21].

Conclusions. The geosituational approach in urban research can significantly improve the urban environment study. The repeatability of urban geosituations and the small data sets that can be obtained using LiDAR surveys provide grounds for their effective analysis and visualization in GIS, as a result of which it is possible to extract urban geosystem properties that can be relevant for the entire city.

Application of quantitative methods for the assessment of landslide susceptibility of the Aghsuchay river basin

Stara Tarikhazer, Seymur Mammadov, Zernura Hamidova — Thu, 01 Jun 2023 00:00:00 +0000

Problem statement. Azerbaijan is making a lot of efforts to reduce the impact of dangerous geological processes on natural geosystems, but they still cause huge damage. To a greater extent, the region of the Greater Caucasus, namely the southern slope, is subject to such processes, where the whole range of dangerous geological processes occurs: earthquake (7-8 b and above), landslides, landslides, screes, mudflows, etc. All of them are large-scale processes in terms of damage - they affect large areas and lead to economic losses.

Purpose - to identify the main factors of the formation and spread of landslides in the basin of one of the most mudflow-bearing rivers not only in Azerbaijan, but also in the South Caucasus - the Agsuchay river, identify the conditions for their formation, assess the risk of the territory's susceptibility to landslide processes, as well as ways to prevent and protect.

Research method. To assess landslide susceptibility and create maps of the potential development of landslides in the basin of the Agsuchay river we used the Frequency Ratio method (FR).

Research results. For minimize damage from landslides on the example of the Agsuchay river basin a detailed study of the factors (hypsometry, slope angles (slope steepness) was carried out by us. Also slope exposure, geological structure (lithology), distance from faults, average annual precipitation, distance to the erosion network, distance to roads and land use) that determine the development of landslide processes with taking into account the mechanism of their development, as well as an analysis of the obtained values of landslide susceptibility and their potential development was studied. In the ArcGIS software environment, using the “Raster Calculator” spatial analysis tool, summing up each landslide factor multiplied by its weights, a map of the landslide susceptibility of the Agsuchay river basin was obtained.

In the river basin Agsuchay we identified over 120 landslide areas. Most of the landslides were recorded along the Baskal tectonic cover, the Steppe Plateau, as well as on the slopes of the Langyabiz ridge, and also partially on the slopes of the Nialdag ridge.

Conclusion. Using the natural boundary classification method in the ArcGIS software environment, the study area was divided into five landslide potential zones: very low, low, medium, high, and very high. The result of the analysis showed that zones with very low, low, medium, high and very high landslide development potential are: 13.75; 24.48; 31.51; 20.51 and 9.74% of the study area, respectively.

Ultimately, the reliability of the obtained models was evaluated using AUC ROC (area under the error curve) analysis, which showed high performance of the method used (82%). Due to the high reliability, the method used can be used to assess the landslide susceptibility not only of the territory of Azerbaijan, but of similar regions of the Alpine-Himalayan belt.

Methodology and practical implementation of research of changes in forest coverage of Volyn region using remote sensing

Vasyl Fesyuk, Iryna Moroz, Mykola Fedonyuk, Oleksandr Melnyk, Serhii Polyanskyi — Thu, 01 Jun 2023 00:00:00 +0000

Introduction. Forests are an integral component of the environment. However, in recent years, there has been a trend towards deforestation in the Volyn region. The main causes of losses were felling and destruction of forests by pests, diseases and fires.

The purpose of the article. The purpose of the study is to develop a methodology for assessing the forest cover of the Volyn region, its verification, assessment of the current state of the forest cover, determination of the trend of change and outline of the main measures to improve the protection and rational use of forest resources.

Methods. Research methods: expeditionary (to study the state of forest cover in a specific area of interest), mathematical statistics (for statistical processing of monitoring results), expert evaluation (to establish the reasons for changes in forest cover), remote sensing (to assess the extent of change in forest cover). Used Ecological passports of the Volyn region for 2017-20, materials of own research, data from web services for monitoring the forests, Sentinel-2 satellite images.

Results. Data on the area of forests and deforestation in the Volyn region, obtained from various sources, are compared with each other. For example, according to EOS Forest Monitoring data, the area of forests in the Volyn region in 2020 was 1,108 million ha, according to Global Forest Watch – 0,733 million ha, according to the results of determining the area of forests in Google Earth Engine – 0,853 million ha. Forest cover was 55,02%, 36,38% and 42,35%, respectively. According to official information from the Ecological Passport of the region – 34%. Such differences are understandable and are explained by the difference in the method of definition. For the period 2001-21 forest losses amounted to 0,103 million ha. The area of non-forest land for forestry purposes is growing. In 2017, their area amounted to 1692.3 ha, in 2018 - 32459.3 ha, in 2019 - 34136.86 ha, in 2020 - 42436.33 ha. Evidently, in 2018, there were changes in the approach to defining these lands. The area of dead forest plantations is decreasing. If in 2017 it amounted to 2915 ha, then in 2018 it decreased by 43.01%, in 2019 - by another 22.36%, in 2020 - by another 33.22%. Most of the forest plantations died from pests and diseases. The above-mentioned decrease in the area is explained by effective and large-scale sanitary felling in previous years. The area of forests destroyed by fires is insignificant. Forest losses were caused by extreme weather conditions in some years (2017, 2019).

Measures for the rational use and protection of forests in the Volyn region are proposed.

The scientific novelty consists in an attempt to compare different assessment methods for a definition of the current state of forest cover in the Volyn region and the trend of its change.

Practical significance is determined by the possibility of using the obtained results for the development of a set of measures for the rational use and protection of forests in the Volyn region.

Processing algorithm of weekly records of the Roztochia landscape-geophysical station thermograph М-16АН as a response source of air temperature data

Bohdan Yavorskyy, Viktorija Chepurko — Thu, 01 Jun 2023 00:00:00 +0000

Formulation of the problem. During the database processing of the Roztochia landscape-geophysical station (RLGS), located in the village of Bryukhovychi, Lviv, an air temperature data gap for 1990–1991 was found. The task of the research was to find those sources about air temperature at RLGS, which would allow us to fill in the gaps during the night hours when, unfortunately, observers did not make measurements.

Problems of further research. In comparison with the method adopted in Ukraine for processing weekly thermograph tapes, in this study, it is proposed to correct the air temperature value during their processing, compensating for accelerated or slowed rotation of the weekly thermograph drum. It is suggested to use only those dry bulb measurements carried out on days with cloudy or rainy weather.

The purpose. The main goal was to find an algorithm for processing weekly thermograph tapes under the conditions of a partial absence of temperature measurements using a dry thermometer by an observer to fill in the gaps regarding night air temperature data.

Research methods. The air temperature values falling during the measurement period were read from the thermograph tapes, and an electronic table was formed. The temperature values (difference estimation) were compared with the corresponding ones recorded in the "Books" of KM-1. At the same time, it was necessary to make two new corrections. The first correction will be made along the ordinate axis, changing the value of the temperature recorded by the thermograph compared to the values of the temperature measured by the dry thermometer. The second correction was made along the abscissa axis, compensating for the drum's slowed down or accelerated rotation.

Presentation of the main research material. A brief description of the proposed algorithm for thermograph tape processing is as follows. In the spreadsheet, in separate columns, we record the temperature values during the observation periods: a) by dry thermometer and b) by thermograph at the points corresponding to the observation periods. Subtracting columns (a) and (b) values, we determine those dry bulb temperature values suitable for calculating corrections. We reject too significant differences that occur during rapid temperature changes. Next, we look for points on the thermograph tape that serve as time benchmarks (the starting and ending points of the temperature curve and the places where the observer draws vertical lines). These temperature values will form column (c). It will additionally include the temperature values obtained by reading the temperature from the tape for rainy and/or overcast days for points whose localization is corrected for time. The difference between column (a) and column (c) will give the temperature correction for several observation periods on each weekly strip taken separately. The last step is the linear interpolation of temperature corrections between neighbouring points of intermediate observation periods.

Practical value. The proposed algorithm may help eliminate gaps in temperature data at other observation points, where the thermograph served as a backup device for recording air temperature.

Research results. The measurements that fall on rainy and overcast weather are best suited for calculating thermograph corrections when air temperature changes slow down. It is necessary to identify benchmark points of time fixation, to which the observer must add the moments of putting on and removing the tape from the drum.

Use of the entropy approach in water resource monitoring systems

Vitalii Bezsonnyi — Thu, 01 Jun 2023 00:00:00 +0000

Effective management of water resources is possible only with an effectively organized monitoring system. After the emergence and development of information theory, the concept of information entropy found its place in the field of the development of water monitoring systems.

The purpose of this work is to review research related to the construction of water monitoring systems and networks that applied the entropy theory in the design process.

Methodology. Entropy terms used in the construction of water monitoring systems are summarized. Recent applications of the entropy concept for water monitoring system designs classified by precipitation are reviewed; flow and water level; water quality; soil moisture and groundwater. The integrated method of designing multifactorial monitoring systems is also highlighted.

Results. The review analyzes studies and their implementation in the design of water monitoring networks based on entropy. The use of various methods of information theory and their adaptation for use in the design of monitoring networks is demonstrated, with the goal of network design methods being the selection of stations that provide the most information for the monitoring network, while being independent of each other. Through extensive testing, information theory has proven to be a reliable tool for evaluating and designing an optimal water monitoring network.

Scientific novelty. This review focuses on studies that have applied information theory or information entropy to construct monitoring networks and systems. Information theory was developed by Shannon in the middle of the last century to measure the information content of a data set and was subsequently applied to solving water resources problems. To date, there are no review studies regarding the design of water monitoring networks based on the concept that entropy will be able to characterize the information specific to the monitoring station or monitoring networks. The main goal is to have the maximum amount of information.

Practical significance. The optimal design of the monitoring network can be built based on the specified design criteria; however, the practical application of a new optimal monitoring network is rarely evaluated in a hydrological or other model. It is also important to identify the benefits of entropy-based network design to convince decision-makers of the importance of entropy-based approaches. The optimal network can be subjective, based on the choices made during the entropy calculation and the design method chosen, especially when additional objective functions are considered in the design. This applies to the method chosen to construct the optimal monitoring network, whether it is found using an iterative method where one station is added at a time, or a collection of stations that are added simultaneously. Research has also shown that data length, catchment scale, and the order can affect optimal network design. when using discrete entropy, it was shown that the binning method affects the final network design. Therefore, when selecting options based on the intended application of the monitoring network, a clear understanding and further research is needed to provide recommendations specific to water monitoring networks. In particular, more work is needed on the spatial and temporal scaling of the entropy calculation data to provide robust recommendations for decision-makers.

Degradation risks and prospects for valley and river landscapes conservation in east Podilsk Transnistria (on the example of the Nemiya river)

Thu, 01 Jun 2023 00:00:00 +0000

Formulation of the problem. The urgency of the problem put forward is associated with the growth of anthropogenic development of the unique valley-river landscapes of the East Podolsk Transnistria is still taking place without a comprehensive geographic justification for the organization of nature management of the territory. These valley-river landscapes are unique in terms of the richness of bio- and landscape diversity.

The purpose of the article is to assess the landscape and biotic diversity of the valley-river landscape of the lower reaches of the Nemiya city of the Mogilev-Podolsk-Yampolsky physical-geographical region in order to form priorities for the environmental activities of Transnistria.

Materials and methods. To achieve the goal, a visual survey of the territory of the Nemia basin was carried out. The studies were carried out on the basis of: hydrological-geographical, biogeographical, botanical and zoological generalizations of the results of route observations in the Nemia River valley. Materials were used, including remote and field observations carried out in the Dniester basin. Also, data from various organizations and institutions were used (Vinnitsa Regional Department of Forestry and Hunting, Basin Water Resources Management of the city of Southern Bug, etc.). In particular, data from rural councils of settlements of the Mogilev-Podolsky urban territorial society were used. In the course of the study, such traditional methods as: statistical, literary and cartographic methods, the method of analogies, the method of comparisons and the method of generalizations were used. At the same time, such specific methods were used: a system of modeling, analysis, synthesis methods, cartographic and mathematical methods and methods of forecasting, expeditionary, continuous survey of natural areas, geophysical, identification of landscape components, etc.).

Results. The study made it possible to study the ecotone of landscape and biotic diversity, including the high vulnerability of anthropogenic valley-river landscape complexes, primarily under the influence of mining and industrial developments. The features of the influence on the formation of these landscape complexes of natural and historical and social conditions were also revealed. At the same time, it was possible to establish the modern anthropogenized structure (landscape, phyto- and zoocenotic) of natural and anthropogenic landscapes within the Nemia River valley.

Scientific novelty and practical significance. The conditions for the functioning of the valley-river landscape, the trends and intensity of its changes under the influence of natural and anthropogenic conditions and factors are analysed. The problems of protective belts and water protection zones are considered to assess the possibility of the Nemiya River performing the function of an eco-corridor in the projected regional ecological network. The factors influencing the ecological state of the valley-river landscape are determined. At the same time, microfoci are identified, with which successional, material-energy, transformational and destabilization changes are associated. Based on the studies carried out, proposals were made for the implementation of environmental protection measures for the Nemia River. The results of these researches can become the basis for monitoring the dynamics, development and evolution of landscapes, primarily for the formation of priorities for the environmental activities of Transnistria.

Ecological and hydrochemical analysis of the rivers Drevlianskyi nature reserve (Ukraine)

Vasyl Konishchuk, Inna Shumyhai, Vasyl Martynenko — Thu, 01 Jun 2023 00:00:00 +0000

Problem statement. The quality of the surface water and ecological condition plays a big role in ecosystems, especially in the hydrochemical regime. The chemical composition and mineralization of river water are in a dynamic link and are formed under the influence of many external factors. Therefore, under the influence of the latter, there was a need to study the hydrochemical composition of the water reserve, which was an urgent issue of the work.

The purpose of the research: comprehensive ecological, hydro-chemical analysis of the state of the rivers of the «Drevlyanskyi» nature reserve for the optimization of environmental protection measures, monitoring, eco-safety and preservation of the biodiversity of hydrobionts.

Research methodology. Conducting research on water quality was based on classical, generally accepted methods: field research, literature review, laboratory research, analysis of the obtained results.

Results. According to research, it was established that within the nature reserve in the summer-autumn period, the water of the main Uzh River and its tributary is moderately fresh in terms of mineralization (0.1–0.6 g/dm³), neutral in pH, and has a hydrocarbon-calcium chemical composition. Insignificant waterlogging of landscapes determines the low content of ammonium nitrogen and dissolved iron in river water. The Zvizdal and Osliv rivers are exception where eutrophication is observed which cauces high runoff of organic substances. It was also investigated that During the summer-autumn period of low water the water contained small amounts of microelements and heavy metals (with the exception of Fe, Mn) which don’t exceed the established sanitary-hygienic maximum allowable concentrations. According to the classification proposed by O.O. Alekin all-natural waters are divided into three classes. According to the content of the main ions and the mineralization of the water, it was analyzed that the water bodies of the nature reserve belong to the calcium hydrogen-carbonate, class of type III. In the water bodies of the nature reserve Drevlianskyi there are water subtypes IIIa-IIIb. The last differ from each other by the presence of magnesium hydrogen carbonate Mg(HCO₃)₂ in IIIa and calcium sulfate CaSO₄ in IIIb.

Scientific novelty. For the first time, a comprehensive analysis of surface waters in radiation-contaminated territories was carried out under the conditions of complete bequest.

Practical significance and research perspectives. The practical value of the research materials lies in the further monitoring of hydroecosystems, the substantiation of environmental protection measures, and the results will be used in the annual "Chronicle of the Nature" program of the reserve for the Ministry of Environmental Protection and Natural Resources of Ukraine.

Biological wastewater treatment plants as sources of environmental pollution by persistent organic pollutants (on the example of Odesa industrial-and-urban agglomeration)

Vladyslav Mykhailenko, Tamerlan Safranov, Mariia Adobovska — Thu, 01 Jun 2023 00:00:00 +0000

Formulation of the problem. Effective mechanism of wastewater treatment (WT) are important components of reducing anthropogenic load on the environment. One of the most widespread mechanisms of urban wastewater treatment is the biological treatment on a Biological Wastewater Treatment Plant (BWTP). However, increasing the nomenclature of pollutants concentrated in urban wastewater seriously affects the effectiveness of WT on BWTPs, which are not intended for such a wide spectrum of specific pollutants such as, in particular, Persistent Organic Pollutants (POPs). The control of their intake into the environment must be regulated according to the Stockholm convention. The goal of the research is the evaluation of the intake of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) into the environment from the wastewater of Odesa Industrial-and-Urban Agglomeration (IUA) and determining the volumes of their accumulation in the sea environment.

Purpose. The assessment of the amount of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) entering the environment with the wastewater from Odesa IUA and determining the amount of their accumulation in the sea environment.

Methods. In our research, all available official methods of calculation of the unintentional formation of POPs were reviewed, as a result – the main and most complete methods were selected: «UNEP (2013). Toolkit for Identification and Quantification of Releases of Dioxins, Furans and Other Unintentional POPs» and «EMEP/EEA air pollutant emission inventory guidebook. Technical guidance to prepare national emission inventories, 2019». For evaluation of PCDD/F accumulation in the sea environment an improved by authors methodology for calculation of PCDD/F accumulation with their cumulative effect and half life taken into account was used.

Results. The work provides justification for the necessity of use of calculation methodologies for determing the intake of PCDD/F to the sea environment adjacent to Odesa IUA; annual massed of PCDD/F entering the sea environment as part of treated, insufficiently treated and untreated wastewater are calculated; massed of PCDD/F that accumulate in waste activated sludge (WAS) on BWTP are calculated; volumes and specifics of PCDD/F accumulation in the sea basin, where the wastewater of Odesa IUA is being discharged to are determined using the improved methodology that enables taking into account the cumulative effect and half life period of these substances; mass and concentration of PCDD/F, immobilized in WAS, are determined, the excess level of concentration of PCDD/F in WAS compared to the maximum permissible concentration is determined. The total accumulation of PCDD/F in the sea environment over 2007-2017 period is determined.

Conclusions. It was established that the use of calculation methodologies for evaluating PCDD/F volumes in the water environment is the only and necessary condition for satisfying the requirements of the Stockholm convention due to the impossibility of performing a regular instrumental monitoring of PCDD/F intake into the water environment. The use of suggested by us improved methodology for calculation of PCDD/F accumulation with their cumulative effect and half-life period taken into account allows for calculation of PCDD/F masses that were formed throughout the year under consideration, taking into account the PCDD/F masses that were formed during previous years as well.

Determination of the macrophyte index MIR as an indicator of water quality in the Pripet river

Alla Nekos, Mariia Boiaryn, Oksana Tsos, Iryna Netrobchuk, Volodymyr Voloshyn — Thu, 01 Jun 2023 00:00:00 +0000

Introduction. The river basin and the catchments of small rivers within it is a complete ecological, hydrological and economic unit with clear boundaries and a set of natural conditions. Increasing the stability of the geosystem of the river basin is impossible without monitoring the dynamics of the state of natural resources and factors of negative impact. A significant part of the water management complex of the Volyn region is the Pripet River basin which has a significant degree of development. The watercourse forms part of the state border between Ukraine and the Republic of Belarus, the tributary basins are located on the territory of both states. The source, lower course and mouth of the Pripet River are on the territory of Ukraine. Therefore, it is necessary to observe the strategic principles of rational nature management to restore and preserve the optimal ecological state of the Pripet River basin.

The objective of the work is to assess the ecological state of the Pripet River using bioindication methods and the Macrophyte Index for Rivers (MIR).

Methods. Research methods are expeditionary, mathematical statistics, bioindication, and determination of the Macrophyte Index for Rivers (MIR).

Results. Four test sites of at least 100 m length each were used to determine the ecological state of the waters of the Pripet River. Research found 48 species of higher aquatic and coastal aquatic plants in the test sites of the Pripet River. All species belong to the division Magnoliophyta, of which 21 species of the class Magnoliopsida (43.75%), and the larger share (27 species, 56.25%) to the class Liliopsida.

35 indicative species of macrophytes were selected in the test sites of the river to determine the Macrophyte Index for Rivers (MIR). According to the MIR classification, the river belongs to lowland watercourses, the macrophyte type M-VIII (organic rivers). MIR calculations established that the river water quality in the test site No. 1 (village of Polozhevo, upper reaches) has a satisfactory ecological state, MIR is 33.84; in the site No. 2 (v. Luchytsi) satisfactory ecological state, MIR is 34.04; in the site No. 3 (v. Liubyaz, border between Volyn and Rivne regions) good ecological state, MIR is 40.6; water quality in the site No. 4 (v. Senchytsi, border with Belarus) has satisfactory ecological state, MIR is 33.57.

Conclusions. According to the Macrophyte Index for Rivers, it was established that the Pripet River waters have a satisfactory or good ecological state. This gives reason to state that the research in the test sites and the MIR calculations fully reflect the ecological state of the watercourse, which allows the use of this research algorithm for other rivers of the basin.

Salinity gradient power using in the Black Sea regions (in frame of the blue growth development)

Mariia Slizhe, Nikolai Berlinsky, Youssef El Hadri — Thu, 01 Jun 2023 00:00:00 +0000

Problem Statement. Today, humanity is in search of new sources of energy to make the economy more sustainable, as well as the need for a transition to energy that works on the principles of Carbon-Free Technology. For the Black Sea, this is expressed in the desire for successful implementation of the program Blue Growth Accelerator, which is aimed at the introduction of innovative technologies and alternative energy sources in the energy sector of the Black Sea countries, for the development of the "Blue Economy" and the achievement of its healthy, productive and sustainable state. Salinity gradient power (SGP) is one of the new renewable energy sources. The most studied methods for obtaining SGP energy are technologies based on: Reverse Electrodialysis and Pressure Retarded Osmosis. The interaction of fresh and salt water can provide, in fact, unlimited, free and clean energy. The basis for the generation of such energy is the so-called salinity gradient that occurs when two types of water are mixed. After decades of work and numerous experiments, scientists have developed a way to use the energy of the salinity gradient to generate electricity. This type of electricity is also called "Blue Energy" by association with the color of mixing freshwater and salt water when rivers flow into the ocean. Places (estuaries or deltas), where rivers flow into the oceans and seas, have a truly enormous energy potential.

The aim of this study is to identify sites in the northwestern Black Sea region with the necessary conditions for the development of Salinity Gradient Power energy, as well as to assess their potential using the example of estimating the maximum theoretical power of the Pressure Retarded Osmosis process.

Research Methodology. In a PRO system, the less concentrated solution flows towards the more concentrated solution due to the positive osmotic pressure difference as long as this difference remains greater than the hydrostatic pressure difference. It is by this principle that osmotic power is produced. Theoretically available amount of energy released when mixing 1 m³ of saturated brine (5 mol/l NaCl solution) and 1 m³ of sea water (0.5 mol/l NaCl) at 293 K is 10 MJ. In the northwestern Black Sea region, along the coast between the Danube and Dnieper rivers, there are 21 limans (lagoons) of which some can be used to generate of Salinity Gradient Power.

Results. The results of calculating the maximum net power showed that highest values obtained in the summer months, when the salinity in limans reaches its maximum and, consequently, its difference with the salinity of sea (river) water increases. Proceeding from maximum net power, obtained for the Western Sivash, where the salinity is maintained artificially at certain values, it can be seen that the annual amplitude has a smaller value, which provides more stable conditions. There are objects in the northwestern Black Sea region, in the waters of which, as soon as technologies become available, it will be possible to implement SGP projects. The Kuialnyk Liman, Sasyk- Sivash lake and Western Sivash have the most favorable conditions, where the highest power indicators are shown when using the sea water – hypersaline solution scheme, in which freshwater is not consumed.

Heavy metals in the bottom sediments of the Sasyk estuary

Ihor Shuraiev, Tetiana Kulaha, Oleksander Paryshev — Thu, 01 Jun 2023 00:00:00 +0000

Purpose. The main aim of research is to study the bottom sediments of the Sasyk estuary, in particular, to establish their lithological characteristics and the peculiarities of the distribution of heavy metals in their layers.

Method. The research was done with the results of the expedition work carried out in 2018-2019, 31 samples of the bottom sediments of the Sasyk estuary, channels and paleochannels of the Kogylnyk and Sarata rivers, and rocks of the shoreline of the studied reservoir were selected. We carried out sampling along the network of 31 stations from a motor boat using a bottom-grab and orientation by GPS navigation. The content of heavy metals was determined using geochemical spectral emission analysis. Statistical and cartographic processing of the research results was carried out using geographic information systems Mapinfo, QGIS, Global Mapper and Surfer. Also, to establish the possible routes of metal migration, we used the analysis of mesotopolineaments formed according to the NASA SRTM digital terrain model, with the construction of rose diagrams of the main directions of the lineaments.

The results. We established that the bottom sediments were represented mainly by grey-black, black, viscous silt, often with an admixture of shell detritus. Less often, they were composed of sand, sometimes muddy with abundant fauna. We also determined the content of heavy metals in the system of bottom sediments, features of their distribution and possible ways of infusing. Thus, in the territory of the Sasyk estuary, heavy metals of the first (Pb), second (Ni, Cu, Cr, Mo) and third (V, Mn, Ba) hazard class are found in high concentrations.

The average content of Pb for the bottom sediment system of the estuary is: for sand – 32 mg/kg, for silt – 41 mg/kg. The maximum content for both is 100 mg/kg. The average Ni content is: for sand – 27 mg/kg, for silt – 62 mg/kg. The maximum content for sand is 80 mg/kg, for silt – 100 mg/kg. The average Cu content in the silt of the Sasyk estuary is 81 mg/kg, and 26 mg/kg in the sand. An elevated content of Mn, Ba and Mo was also found in several samples.

Оften areas with increased concentrations of metals have a point character. In almost all cases, they are connected to the river systems adjacent to the pond. The distribution of some metals is correlated with the main directions of estuary water circulation. Wastewater is a likely sources of metals entering the estuary geoecosystem. We also assume that the migration of these elements to the pond may occur through tectonic blocks.

Scientific novelty. For the first time in recent years, we have carried out expeditionary work on research of the bottom sediments of the Sasyk estuary, along the complete network of the station. We obtained the data on the gross content of heavy metals, and determined their average, maximum and minimum concentrations. For the first time, maps of the spatial distribution of metals were constructed, which made it possible to establish the main regularities of their accumulation in the bottom sediment system of the pond.

Practical significance. Pollution of the bottom sediments of the Sasyk estuary with heavy metals is one of the components of today's critical ecological state of the pond, which affects the well-being of the residents of the surrounding areas. The obtained results can be used at the state level to create effective programs for quality management of the resource potential of the estuary.