Vol. 59 No. 2 (266) (2025)

Тhe natural flow of water resources is decreasing annually due to global warming. Under the current conditions, the development of new groundwater sources for the settlements of Armenia is becoming an important task. The article reviews methods for assessing natural and operational groundwater resources based on hydrogeological studies conducted in the basin of the upper reaches of the Aghstev River, in the middle of the settlements Margahovit and Fioletovo of the Lori Region of the Republic of Armenia. Groundwaters of the artesian basin can be operated by gravity for drinking water supply of Dilijan and other settlements located downstream of the Aghstev River. In the settlements of the northern and southern regions of the Republic of Armenia, located outside the Central Volcanic Highlands, groundwater reserves are insufficient to ensure drinking water supply. Therefore, river water intakes are used here. However, river waters are subject to anthropogenic impact and pollution during seasonal floods. The Margahovit groundwater basin is composed of Quaternary lake-river sediments, represented by alternating layers of loose-fragmental and clayey rocks with an average thickness of 165 m. In the basin, a groundwater aquifer and two confined aquifers have been identified. The confined aquifers, which are hydraulically interconnected and have the same qualitative characteristics, are of practical importance for drinking water supply. This work presents the geological and hydrogeological conditions of the upper reaches of the Aghstev River. The groundwater operational reserves for drinking water supply to the settlements are calculated and substantiated. Methods for treating water with high levels of iron, manganese, and fluoride are presented.

The article examines a territory that covers part of the Pambak and nearly the entire Tsakhkunyats mountain ranges. The research led to the discovery of new crypto structures, refinement of the orientations of previously known faults, and identification of ring- and arc-shaped structures. It was found that three ore fields can be distinguished within the territory, where gold mineralization is predominantly developed. The ring- and arc-shaped structures do not play a role in the localization of mineralization. Instead, the mineralization is located at the intersections of faults with different orientations and within a regional fault zone. Promising areas for the discovery of gold mineralization include sites where the zone of hidden NE trending faults in the southern part of the region intersects with major NW trending faults. In connection with the sharp rise in precious metal prices, the prospects for increasing their reserves should also be linked to a detailed additional study of ore occurrences located within these ore fields.

The results of studies of the pozzolanic properties of zeolite tuffs from the Lerantsk mine in the Shirak region of RA have been presented. The laboratory tests have been shown that the addition of 5–20% zeolitic tuff to the cement clinker increases the strength of the cement stone by 21–24% over 28 days, due to the pozzolanic properties of the zeolite. In the process of clinker hydration, zeolite converts calcium hydroxide into the calcium hydrosilicate, as a result, calcium hydroxide is prevented from leaching out of the cement stone by about 40% and provides increased strength of the cement stone. It has also been found that the addition of zeolite tuff to the clinker leads to an increase in the specific gravity of the cement and a reduction in the initial and final setting time.

The article is based on the materials of field mapping of surface loose formations and relief-forming processes on a scale of 1:25 000 of the Getik River basin. An analysis of the river basin network and the morphological features of its valley revealed a number of inconsistencies that contradict the current direction of the river. In the Late Pliocene-anthropogenic period, a significant restructuring of the river network took place here – the main river changed the direction of its flow from South-East to North-West. This restructuring is reflected by inconsistencies in the high order of the tributaries of the Getik River, the presence of multilevel terraces, the flat nature of the river with a meandering channel, traces of a paleolake with sufficiently thick lake clays in its modern upper reaches, which contradicts the geomorphological patterns of the river valley development. For the first time, the outlines of the paleolake, which was formed in front of the Chambarak pass, have been outlined. The current tectonic activity of the Getik River basin is emphasized by its high seismicity, the presence of deep and regional faults, and the widespread occurrence of numerous active landslides on both slopes of the main river valley and its tributaries.

The article discusses the current picture of public perception of sustainable tourism in Gegharkunik Region. The purpose of the work is to study and identify how much the population of Gegharkunik Region is aware of sustainable tourism. In the course of the work, a study was conducted and an electronic sociological survey was conducted to understand the current perception of sustainable tourism. The analytical results of the sociological survey showed that the implementation of the concept of sustainable tourism undoubtedly requires targeted and coordinated steps, from the very beginning giving specific attention to overcoming barriers of insufficient awareness of the population. In the region, the public perception of tourism as a priority sector of the economy, its role and importance, its decent assessment and proper use are now vital. Conversely, incorrect public perception, underestimation and irrational use of resources become a problem. Sustainable tourism is important both for the preservation of the environment and for the socio-economic development of the region and communities. In the region, it should be based on the principles of rational use of natural resources, preservation of cultural values and social justice. Proper public perception in this area can have a significant impact on the development and dissemination of sustainable tourism ideas. Daily human activities lead to environmental degradation in combination with a significant increase in mass tourism․ In this case, the negative impact of the anthropogenic factor on the environment as a result of mass tourism is obvious, which becomes a serious challenge for the environment. Sustainable tourism in this case serves as a methodological platform for all types of tourism.

The study examines the characteristics of the intra-annual distribution of the Syrdarya River runoff under conditions of water management regime transformation. Based on the analysis of hydrological observations from the section between the village of Kal and the downstream of the Chardara Reservoir, changes in the seasonal runoff structure during wet, average, and dry years have been identified. Following the transition of the Naryn basin reservoirs to an energy-oriented regime since 1991, peak discharges have shifted to the autumn-winter period, accompanied by a reduction in summer runoff, which has complicated irrigation water supply. A comparative assessment of seasonal runoff distribution was carried out for the periods 1980–1990 and 2011–2021. The necessity of constructing regulatory reservoirs in Uzbekistan and Kazakhstan to stabilize water availability has been substantiated.

On the occasion of the Professional Days of Forester, Hydrologist and Meteorologist, at the initiative of the Faculty of Geography and Geology of YSU, with the financial support of the Committee on Higher Education and Science of the RA Ministry of Environment (Research Project No. 24WS-1E035), an international three-day conference entitled “Current Issues in Hydrometeorology and Environmental Monitoring in a Changing Climate: Adaptation, Sustainability and Production Process” was held from March 20 to 22, 2025.

During the conference, the achievements and prospects of the development of fundamental and applied scientific research in the field of hydrometeorology, environmental monitoring, biodiversity and ensuring ecological safety were discussed and presented, the priority issues, development patterns and prospects in the field of hydrometeorology were identified and revealed, the problems of economic management of the development of modern society and legal regulation of the ecosystem were assessed, the role of the latter in solving the socio-economic problems of the region was assessed, the current state of the environment, and the issues of climate change were analyzed and assessed. 65 reports were made in offline and online formats, a significant part of which has great scientific value and great scientific-applied potential. In total, more than 200 participants (in person and online) participated in the conference, including state officials, representatives of international organizations, representatives of Armenian and foreign universities, and famous people. The conference was attended by renowned scientists from France, Germany, Russia, Uzbekistan, Belarus, and Tajikistan. The main achievements of this scientific event were the expansion of international cooperation and the exchange of experience.

At the end of the conference, the speakers were awarded certificates and letters of appreciation.

In this study we investigated the effect of saline solution in different concentration (0.1–1.0 mM NaCl) on the development of conidial inoculum of powdery mildew pathogen Blumeria graminis (DC) Speer. on soft wheat Triticum aestivum L. Dynamics of development and of differentiation of infesting structures of the powdery mildew was investigated using scanning electronic microscopes. After the salt solutions were added, the conidial germination of powdery mildew fungi was slow, but germ tubes were formed, appressoria were not formed. It is assumed that the action of various unfavorable factors is based on a common mechanism associated with an increase in the level of active oxygen forms in plant tissues.

The article discusses the issues of managing the risks of climate change impacts on viticulture in mountainous areas, the complexity of which requires a spatio-temporal study. The article chooses Vayots Dzor as an example, which is a typical mountainous area and is considered an ancient region rich in viticultural traditions. Here, there is a variety of interconnected agroclimatic conditions necessary for viticulture and obvious risks of climate change manifestations, which together make Vayots Dzor a typical object of geoecological research. Such research is not only of scientific and methodological interest and is useful for studying the agroclimatic conditions of other mountainous viticultural areas, but also, with its practical orientation, can contribute to the scientific understanding of the climate change problem observed in Vayots Dzor and risk management. The article presents the results of the calculation and analysis of the spatial-temporal distribution of agroclimatic resources in Vayots Dzor. The following main agroclimatic indices were used: the sum of active temperatures, the number of days with temperatures above 30℃, the average of absolute minimum temperatures, and the amount of precipitation during the vegetation period. As a result of the study, some changes in the agroclimatic conditions of the area over the past decades have been revealed, and agroclimatic areas favorable for viticulture have been identified. It has been found that within the scope of climate change resistance and adaptation risk management, there are new opportunities to expand the viticultural areas in Vayots Dzor and to develop the cultivation of valuable grape varieties.

The article analyzes the impact of climate change on forest ecosystems in Armenia. Historical and projected climate data were studied, and the impact of changes in temperature and precipitation on forest distribution, species composition and biodiversity was assessed. The article also presents climate change maps and vulnerability analysis of forest areas. Mitigation and adaptation strategies are proposed, including the use of drought-tolerant species, fire and pest management systems, and conservation of genetic resources. The article also emphasizes the need for a systemic and localized approach to forest policy development and biodiversity conservation.

The article examines the adaptive capabilities of wintering crops in the conditions of irrigated lands of Uzbekistan to various abiotic (light, moisture, temperature, soil conditions, etc.) stresses affecting their preservation, growth, development, as well as the productivity of biomass, seeds and grains, and provides results on photosynthesis and respiration of winter crops. The results on biological and ecological characteristics of winter crops, as well as modern ideas about adaptive conditions in connection with their climatic capabilities are given.

The work is devoted to modeling the level regime of the Arpi Lake-reservoir. The multiple linear regression apparatus is used, with the help of step-by-step exclusion of predictors, a statistically adequate and physically justified model is selected. The article describes the possibility of replacing atmospheric precipitation as a function of the influence on the water level with indirect factors such as relative air humidity. The model is derived from standardized data with monthly discreteness, an assessment of the model's effectiveness is given on dependent and independent material.

The article is devoted to environmental and social aspects of irrigation development in Uzbekistan under climate change.  Irrigation development in Central Asia, especially in Uzbekistan, is a key element for ensuring food security and sustainable agricultural development in arid climate conditions. However, this process is accompanied by significant environmental and social consequences. The article discusses the main environmental problems such as loss of water resources, reduction of biodiversity, soil salinisation and pollution of water bodies. Social impacts are also discussed, including population migration, conflicts over resources and changes in traditional ways of life. Particular attention is paid to the lack of consideration of environmental and social factors in the planning and implementation of irrigation projects, which can lead to increased negative impacts. The article emphasises the need for an integrated approach to water resources management, including adaptation to climate change, introduction of water-saving technologies and regular environmental assessments. The relevance of the article is justified by the existing need for balanced development of irrigation systems, which should take into account both the needs of agriculture and environmental protection. It is recommended to involve local communities in the process of planning and project management, as well as to conduct educational programmes to raise awareness of sustainable use of water resources.

The present study is devoted to the development and validation of a unified methodology for integrated geo-ecological diagnostics of the state of sources of decentralized domestic drinking water use. The Voronezh region with a population of 2.285 million people and a developed industrial-agrarian structure of the economy was chosen as a model region. The proposed methodology is based on a set of scientific and methodological approaches to the collection, analysis, processing and presentation of information on the quality of drinking water, levels of environmental risks to public health based on the methods of probabilistic-statistical analysis of eco-geodata, geoinformation modeling and mapping technologies.

In the context of increasing anthropogenic pressure on natural and nature-technical systems, the assessment of environmental impact requires a more qualitative systemic toolkit. The task of determining ecological well-being in the context of assessing a system's impact on nature and society is fundamental to fulfilling every person's right to live in an environment conducive to their health and well-being. The aim of this work is to obtain an integral assessment of this systemic property – to determine the comprehensive impact of a complex natural and nature-technical system on nature and society from the perspective of ecological well-being. To achieve such a systemic property, a method of summary indicators is applied, allowing the transformation of a set of criteria into a clearly defined integral indicator of the assessed property.

An analysis of the average annual and monthly characteristics of the relative air humidity (RAH) regime in the Minsk City showed that in 1980–2022. In the City, RAH is characterized by small interannual and significant seasonal variability, as well as a tendency to a slight increase in its annual values. The average annual RAH was 77․3% with a C_v of 2․20%. The number of days with RAH ≥80% is characterized by moderate temporal variability and a tendency to decrease their number. The average annual number of days with RAH ≥ 80% was 176 days, with a C_v of 9․69%. An analysis of the seasonal dynamics of RAH in Minsk showed that its highest values were observed in winter and amounted to 86․0%, with a C_v of 1․73%. In spring, RAH was the lowest of all seasons of the year – 69․6%, with a C_v of 4․14%.

The results of the meteorological data analysis for a 20-year period in the southern taiga and subtaiga of Western Siberia showed a spatio-temporal variability in the duration and intensity of frosts. The highest probability is recorded throughout the territory in the first decade of May (from 70% to 90%) and falls at the beginning of the growing season of agricultural plants. The probability decreases to an average of 40% to the end of May, The probability of frost is about 10% in the first decade of June for the North-Western part of the study area. In the region as a whole, frosts they cause significant risks to the sustainable functioning of the local crop production system. Against the background of an increase in the duration of the active growing season, there is a high probability of frost in subsequent years.

Eight potentially toxic elements (Mn, Ni, Co, Cr, Cr, Pb, Zn, Cd, As) in soils formed on the territory of the industrial site of the Udachny Mining and Processing Division were considered in this study. The Potential Environmental Risk (RI) was calculated to determine environmental risks of soil contamination. The concentrations of potentially toxic elements decreased in the following order Mn > Ni > Zn > Co > Pb > Cr > As > Cd. 19.51% of the sites in the study area exhibited a high potential environmental risk for Mn and Ni, while only 4.87% exhibited a low potential environmental risk for other potentially toxic elements. The greatest impact on soils contamination are exerted by the areas of the "Udachny" and "Zarnitsa" pipes, tailings ponds and the areas highly mineralized water outlet. The five main diverse sources of PTEs in this study area's soils were natural, mining activities, transportation, industrialisation, as well as highly mineralized waters.

In the context of global climate change, the assessment of carbon balance at the regional level is becoming increasingly important for developing effective strategies for greenhouse gas emissions management and adaptation to current climate trends. Terrestrial ecosystems play a crucial role in the global carbon cycle, making varying contributions to carbon dioxide exchange between the underlying surface and the atmosphere. In this study, a machine learning-based model was developed, specifically utilizing the CatBoost gradient boosting algorithm, for comprehensive assessment of spatiotemporal variability in net ecosystem exchange of CO₂ (NEE). The results of model experiments for Sakhalin Island in 2023 demonstrated that this approach effectively accounts for multiple factors affecting carbon exchange and provides spatial distribution of CO₂ fluxes at a regional scale with monthly temporal resolution. The developed model showed high prediction accuracy with a coefficient of determination (R²) averaging 0.76 across all ecosystems. The obtained results can be applied for carbon balance assessment in other regions and development of measures to mitigate anthropogenic impact on the climate system.

The effects of climate change are particularly pronounced in high-latitude regions, with polar environments showing heightened sensitivity to environmental shifts. Plant responses to these alterations are primarily observable through changes in ecosystem processes, especially in terms of water vapor and CO² exchange patterns. This research investigated the seasonal patterns of CO² net ecosystem exchange (NEE) and heat transfer (both sensible and latent) in two Northern Siberian ecosystems: a subarctic palsa mire and a mature larch forest. The investigation, spanning from 2019 to 2023, employed eddy covariance techniques to gather new data on how these ecosystems respond to atmospheric changes. The findings revealed that both sites consistently uptake more atmospheric CO² than they released, despite fluctuating weather conditions between years. During growing seasons, the palsa mire’s NEE readings ranged between –62.9 and –120.2 gC·m^–2 while the larch forest showed values from –63.5 to –83.6  gC·m^–2.  The heat flux measurements demonstrated substantial year-to-year variability, which was largely influenced by changes in solar radiation levels and rainfall patterns.

The paper examines the impact of climate change in the South of Western Siberia on human health, recreational activities and a number of economic sectors: transport, construction, agriculture, and thermal power engineering.

The investigations are related to the development of the methods of total water demand estimation for the crops cultivated in the irrigated conditions of different agricultural zones. The agro-climatic indicators recorded in 2015–2019 by 10 hydrometeorological stations served as baseline data. The maximum crops water demand per decades has been calculated via CropWAT software. The soil moisture monitoring results enable to disclose the effect of various evapotranspirations on the moisture dynamics in the soil. The changing pattern of the crops total evaporation speed at different values of soil depth has been disclosed, while based on the mathematical processing of the experimental results, a calculated formula has been derived, which enables to solve the problem of crops coefficient calculation in non-standard conditions. The new mathematical model for the detection of moisture change in the soil, depicts the soil moisture regime more precisely, which enables to describe the dynamics of total evaporation from the soil and plant surfaces for the period of irrigation intervals in more precise manners.

The results of the research pertain to the enhancement of the efficiency in utilizing the effluent waters from fish farms operating within the administrative boundaries of the Sis, Ranchpar and Hovtashat settlements in the enlarged Masis community. The study addresses the optimal utilization of agricultural lands and the development of a sustainable economic development model, aligned with the principles and requirements of Permaculture design. To achieve this objective, a comprehensive analysis was conducted on the groundwater effluents discharged from the aquaculture enterprises in the aforementioned settlements. The chemical composition and various quantitative parameters of these waters were examined. Additionally, the extent of waterlogged areas, their distribution zones, and the potential adverse effects on the fertility of agricultural soils and the surrounding environment were evaluated. In order to mitigate these negative impacts, a Permaculture-based remediation model was developed, and the feasibility of implementing this model was substantiated as a means of reducing the ecological negative consequences of aquaculture activities, while laying a foundation for the sustainable development of the economy.

The fluctuating asymmetry (FA) of a plant leaf is used for bioindication and environmental monitoring. However, the specific features of FA responses of various leaf traits to air pollution have not been studied sufficiently. Analysis of this issue using the example of Betula pendula and Tilia cordata leaf with roadside air pollution has shown that FA did not change in the polluted areas in the species, which is more resistant to pollution (T. cordata). However, in the species, which is more sensitive to pollution (B. pendula), there was an increase in the FA of three out of five leaf measurements in the pollution gradient, while the integral FA indicator did not change. Thus, when using the FA of a plant leaf in monitoring, it is necessary to take into account the species resistance of plants to pollutants and the different sensitivity of the leaf FA traits to air pollution.

Storm surge phenomena are one of the most dangerous natural processes observed in the coastal zone of the sea. Dangerous extreme surge level fluctuations are observed at a wind speed of more than 15 m/s. The Sea of Azov has had a constant increase in its level over the past hundred years. During the period 1991–2016 216 cases of extreme level fluctuations were observed in the coastal zone of the sea. The level rise averaged 0.18 cm/year over the study period. Level rises cause significant destruction of the shores of the Sea of Azov, coastal abrasion reaches up to 6 m/year.

The study is aimed at identifying the relationships between the natural and climatic conditions of small-leaved linden growth sites and their nectar productivity. During a comparative assessment of the nectar productivity of small-leaved linden plantations and hydrometeorological data (hydrothermal coefficient (HTC), Pedya Aridity Index) from 2018 to 2023 in the territories of protected areas located in different natural and climatic conditions of the Republic of Bashkortostan, it was found that in 2019 there were the most optimal conditions for nectar secretion of linden plantations. In the fall of 2018, according to the Pedya Index, it was noted that in the Zilim Nature Park, during the entire warm period, there were "normal moisture conditions", which made it possible to obtain maximum nectar production in 2019 under conditions of optimal moisture supply (HTC = 1.81) was 397.2 ± 39.7 kg/ha. In the Shaitan-Tau Nature Reserve in 2019, during the linden flowering period, drought conditions observed, according to the Pedya Index, and nectar production was only 232.8 kg/ha. Optimal hydrothermal conditions allow plants to develop well and produce more nectar. Hydrometeorological indicators of the previous year can be used to predict potential nectar productivity in the current year. For example, if the previous year was wet and warm, this can have a positive effect on flowering and nectar secretion in the current year.

This article discusses the possibility of joint use of pneumatic tanks and pumps with an adjustable drive in local water supply systems. An overview of existing studies and existing methods for calculating pneumatic accumulators, as well as their effectiveness, is presented. The results of bench tests of pneumatic tanks and pumps with an adjustable drive are presented in order to determine the most effective areas of their operation. Further steps for research in this area are outlined.

The objective of this study was to identify spatial and temporal relationships between changes in climatic parameters, such as temperature and precipitation, and land use and land cover dynamics on the Kerch Peninsula for the period 1990–2020. The classification of Landsat multispectral images (TM, ETM+, OLI) utilizing a convolutional neural network resulted in the identification of eight LULC classes. ERA5 climate data were corrected using U-Net neural trained on data from four weather stations in the study area, thereby increasing the final accuracy. Spearman's pixel-wise correlation analysis revealed negative correlations of temperature with LULC in areas of artificial landscaping (forested areas, farmland), where vegetation reduces localized warming through evapotranspiration; positive correlations in the Southwest, where aridization and temperature increase are accompanied by a transition to low-productive classes (bare soils, barren lands); support of grass cover in the Northwest and increased degradation in urbanized and lakeside zones in the Southeast.

The article deals with some issues of climate shift and its impact on the development of the economy and civil society in Belarus at the present stage. In particular, the following areas have been highlighted and discussed: the impact of climate change as a whole on the global community, as well as social and economic consequences. The development of the Republic of Belarus under the conditions of climate transformation in such spheres as agriculture, energy, and tourism was analyzed. The contribution of the republic to the reduction of total greenhouse gas emissions is emphasized.

The article deals with the issues of design and its influence on the development of ecotourism in Belarus through the creation of unique impressions and effective solutions. The impression industry tends to emphasize emotional and personal interaction with tourists, which contribute to the strengthening of the tourism industry and improving the level of service, both to the population of the republic and foreign guests. The importance of integrating design into ecotourism organization is emphasized to improve the efficiency and competitiveness of the industry. The study also revealed that the use of design solutions contributes to the preservation of natural resources and promotes the propaganda of careful attitude to nature. It is concluded that design is a powerful tool for shaping unique tourism products and enhancing the experience of visiting eco-friendly destinations.

The paper presents an analysis of changes in climatic parameters (air temperature, relative air humidity, evaporation, precipitation and wind speed projection) in the Khemchik–Kurtushibinsky district of mountain steppes, mountain-taiga grass larch forests of the Republic of Tyva. The insufficient number of meteorological stations and the lack of data on altitude levels motivated the use of ERA-5 reanalysis data. The assessment was carried out on the basis of data for the period 1961–2020 in the altitude range from 500 to 2200 m and more a.s.l. Trends in changes in the main climatic data were identified, the rates of their changes were calculated, and anomalies were assessed. The results show significant changes in climatic parameters, especially at altitudes of 500–1000 m a.s.l., which may be associated with global climate change.

The changes of Moscow climate over 245 years of regular meteorological observations have been studied. It is shown that, on average, over the entire period from 1780 to 2024, the air temperature (Т) on the urban periphery increased at a rate of 0.012℃/year, and in the center of Moscow – at a rate of 0.017℃/year, which is partially due to the influence of the urban "heat island". In the background rural area of the Moscow Region at the latitude of Moscow, Т increased by no less than 1.5℃: probably by 2.0℃ over 245 years. Warming is stronger in the winter and spring months: the excess of the modern climatic norm for the period 1991–2020 compared to the conditions of the late XVIII century is statistically significant from December to April and on October. As a result, the amplitude of the annual air temperature cycle and the degree of continentality of the Moscow climate are gradually decreasing. No stable cyclicality with periods longer than a year was detected in the changes of Т.

This article analyzes the occurrence of very strong (including squally) winds during the cold season in the territory of the Republic of Belarus in a changing climate (from 1989 to 2022). The repeatability, spatial and temporal features of the distribution of such wind from November to March, as well as the trends in the development of a hazardous hydrometeorological phenomenon in a changing climate are presented. In addition to the physical and geographical conditions of weather stations, which affect the spatial and temporal distribution of the phenomenon under study, surface synoptic and high-altitude aerological conditions are determined, contributing to the strengthening of the wind to the criteria of very strong. The main weather recommendations for forecasting very strong (including squally) winds during the cold season are proposed.

In contemporary natural-anthropogenic complex conditions, the physical processes of the formation of winter river flow in the Sevan basin are considered using ground-based data. The values of winter water flow were calculated for 12 measuring posts on rivers that have a number of observations of 50 years or more and flow into Lake Sevan. The dependencies of the winter river flow on the river slope from the most distant point and the area of their catchment areas have been identified. It has been established that the main factors influencing the increase in winter river flow in recent decades are an increase in average daily air temperature, as well as an increase in the number of winter thaws. It was found that at all hydrometric points there is a decrease in the number of days with ice phenomena. At the same time, a close connection between winter runoff and days with ice phenomena could not be established. We plan to conduct more detailed studies on this in our future work.

In recent decades, there has been an increase in the number of dangerous phenomena in the southern taiga of Western Siberia, with the greatest increase occurring during the growing season. Late spring and early autumn frosts, heavy and prolonged precipitation, low humidity, and high wind activity have a significant negative impact on crop production in the region under study. The paper presents the result of a decadal analysis of a complex of dangerous and adverse events, which allowed us to assess the temporal dynamics and identify the features of the spring–summer, summer and autumn seasons of the growing season.

The water balance components of the river basin of the River Zeravshan, which is characterized by significant anthropogenic load, are considered. The hydrometeorological study of the territory is assessed, the statistical hydrological characteristics are analyzed, and the significance of trends in the series of observations of air temperature, precipitation and river runoff is assessed. It is found that trends are present only in two of the eight series of observations of temperature, the hydrological series and series of precipitation do not have trends. The evaporation calculation formulas are assessed. The water balance assessment showed that the incoming component is spent almost entirely on the catchment area of the River Zeravshan, including the use of water for industrial and municipal purposes.

In the article the abundance, taxonomic composition and degree of similarity of heterotrophic bacterioplankton communities were determined in Lake Vishtynetsky, Kaliningrad Region. The analysis of abundance, taxonomic composition and degree of similarity of heterotrophic bacterioplankton in a freshwater body allowed us to reveal differences in its composition. We found that the quantitative indices of bacterioplankton varied insignificantly from 0.1·10³ CFU/mL to 0.4·10³ CFU/mL. Bacterioplankton abundance increased in the central and southern parts of the reservoir.  Comparison of the similarity of bacterioplankton communities using the Czekanowski coefficient in the selected zones revealed a high percentage of similarity between all the studied communities of more than 50%. The distribution of bacterioplankton of this water body is expressed through numerical heterogeneity and different qualitative composition.

The ecological state of several flooded quarries in the Kaliningrad Region was studied: Yantarny, the largest in area, formed as a result of filling the basin of a former amber quarry, as well as Berezovsky and Pushkarevsky, which were previously used for sand and gravel extraction. The results of hydrochemical studies showed that all the studied water bodies are in a good ecological state, but water quality in the Yantarny quarry is in a better ecological condition. According to zooplankton indicators, the water quality in all the studied quarries is assessed similarly, but in the Yantarny quarry, lower values of trophicity, trophic index and saprobity coefficients of water are noted, which also indicates better water quality in it.

Based on the analysis of the long-term dynamics of annual and seasonal values of the main meteorological characteristics for 36 weather stations, the values of the moisture balance for warm, cold periods and for the year were established both in the Rostov Region as a whole and in zonal landscapes. There is a clearly defined annual course of the moisture balance. A positive moisture balance is observed in winter for all weather stations in the region and in all zonal landscapes, and the maximum disadvantage is in summer.

Model experiments were conducted to estimate the spatial variability of the wind field and carbon dioxide fluxes at different levels over a highly heterogeneous forest area in the Lyalsky Nature Reserve in the Republic of Komi, Russia (62°16'28" N, 50°39'54" E). Calculations were performed using a three-dimensional, Reynolds-averaged Navier-Stokes (RANS) hydrodynamic model of greenhouse gas transport. Lidar measurements of vegetation and topography from unmanned aerial vehicles, chamber measurements of CO₂ fluxes near the soil surface, and ERA5 reanalysis data were used as input parameters for the model. The model experiment results showed significant spatial variability of the wind field and CO₂ fluxes within and above the forest canopy. This variability is determined by surface topography roughness and vegetation mosaic structure. Comparing the simulated fluxes with the fluxes measured using the eddy covariance method at a long-term monitoring station revealed good agreement between the model calculations and the measurement results in the area adjacent to the station. However, significant spatial variability of vertical fluxes within the model area makes extrapolating point flux measurements to the entire study area problematic.

One of the important characteristics of the thermal regime of lakes is the ice regime, which affects the entire lake ecosystem. At present, remote sensing methods, in particular the NDSII spectral index, allow to observe the ice cover, map it and carry out its cartometric studies. The purpose of this study is to assess the possibility of using satellite remote sensing data for analyzing the ice cover of Lake Sevan and studying its ice regime. The remote sensing data of Lake Sevan confirm the increase in the frequency of its freezing as a result of lake water level decrease. Analysis of the results of Lake Sevan ice cover mapping showed that NDSII>0.5 corresponds to complete freezing of the lake.  As a result of application of remote sensing data, both the possibility and necessity of their use for studying the ice cover and ice regime of Lake Sevan were revealed and confirmed.

In high-mountain areas, glacial lake outbursts often cause floods and extreme events. The study of such phenomena is especially important in the context of ongoing intensive glacier melting and climate change. This study is devoted to the monitoring of the Bashkarinsky glacial lakes after their outburst on September 1, 2017. The lakes are located in the most densely populated part of the Central Caucasus, in the Elbrus Region. After the outburst, the lake system became flowing, but since then it has undergone significant changes, remaining unstable and potentially dangerous. The study used remote sensing data and field observations to assess the state of the Bashkarinsky Lakes. Potential scenarios for a repeated outburst of Lake Bashkara were also simulated based on the STREAM_2D hydrodynamic model.

To evaluate potential fire danger based on weather conditions the region of South Siberia's Mountains (80–110º E and 50–58º N) we used a correlation relationship between a number of days with high fire danger (Nesterov Index > 1000) and the hydrothermal coefficient (HTC) of Selyaninov (Malevsky-Malevich et al., 2005), which is a ratio of monthly temperature to precipitation. Based on predicted HTC at 2040–2060 derived from the climate model INM-CM5-0 and moderate (ssp 126) and extreme (ssp 585) scenarios of CMIP6, "hot spots" of dryer climates and increased numbers of days with high fire danger were mapped across the study region with a focus on mountain forests.

The Hrazdan River is the largest water vein in the central part of the Republic of Armenia. It flows through the capital Yerevan and more than 60% of the country's population lives in the catchment. Thus, the study of water use opportunities is gaining both scientific and practical importance. Swimming in rivers, as a recreational activity, is one of the most valuable cultural ecosystem services. To assess its potential, a microbiological study of water was carried out in 2023, the coli index and the quantitative composition of saprophytic bacteria were determined at 16 observation points. The results show that there were no violations of the norms set for recreational water use in Solak, Argel, the upper course part of the Bjni tributary and along the course of the Marmarik tributary.

The hydrochemical composition of the largest lakes in Yakutsk – Beloye, Khatyng-Yuryakh, Ytyk-Kyuel, Sergelyakh, Saisary, was analyzed based on a comprehensive study from 2009 to 2023. The studied lakes are predominantly sodium hydrocarbonate with medium mineralization and moderately hard water. The main contribution to the total volume of cations is made by Na⁺ and Ca²⁺, HCO₃^– and Cl^– anions. A decrease in mineralization with a low approximation reliability is observed. Variation in water hardness values directly depends on the content of Ca²⁺ and Mg²⁺ cations and HCO₃^–. The average value of suspended solids is significantly higher than the existing Maximum Concentration Limit (MCL), the change in their content in each lake is individual, the highest was found in lakes Beloye, Saisary and Khatyng-Yuryakh. The most significant factor in the formation of the hydrochemical regime is mineralization and water hardness. The established patterns are characteristic in general for the entire sample, which reflects the specifics of the formation of the hydrochemical regime of urban lakes. The microelement composition is characterized by an increase in the concentrations of Pb, Ni and Fe. Ecological and geochemical analysis showed that the most polluted lakes are Beloye, Saisary and Khatyng-Yuryakh.

Remote sensing technologies provide an effective means of monitoring forest ecosystem changes without the need for direct field observations. This study investigates changes in forested areas of the Syunik Region, focusing on the impacts of forest fires, illegal logging, and tailings dumps. SENTINEL-2 satellite imagery was processed and analyzed using the Normalized Burn Ratio (NBR), Normalized Difference Vegetation Index (NDVI), and Normalized Difference Moisture Index (NDMI) to detect and quantify vegetation loss and degradation over different time periods. Comparative analysis of multi-temporal satellite data revealed significant alterations in forest cover, highlighting the effectiveness of remote sensing methods for detecting deforestation trends and assessing environmental consequences. The findings underscore the importance of satellite-based monitoring for sustainable forest management and conservation efforts.

The agroforestry system combines the best features of agricultural practices and forest ecosystems. This approach provides diverse environmental and socio-economic benefits, such as preventing soil erosion and degradation, increasing soil moisture and water retention, and yielding harvests from planted fruit trees, bushes, edible plants, and various agricultural crops. Additionally, agroforestry offers several added benefits, including enhanced biodiversity, beekeeping and improved pollination, carbon sequestration, and climate change mitigation and adaptation. With these advantages in mind, a 3.5 ha model agroforest was established in 2022 on the Southern bank of Lake Sevan, near the village of Tsovinar in the Martuni consolidated community. Over two years of project implementation, all major activities and system-forming elements were put in place, including fencing, an irrigation system, and the planting of approximately 10 000 tree and bush species, along with edible plants. This model, through further monitoring and evaluation, could provide strong justification for the Government of Armenia to expand its forest cover in alignment with its international commitments under the 2015 Paris Climate Agreement.

The analysis of changes in the temperature regime in the Altai-Sayan Mountain country and in the Caucasus in the Republic of Armenia is presented. The values of slope coefficients of linear air temperature trends in mountain basins and wide valleys were obtained. Temperature trends at the highest mountain stations close to the free atmosphere were studied. Standard 30-year climatic periods recommended by the World Meteorological Organization were used. Features of similarities and differences in temperature trends up to 2020 were considered. It was shown that it is important to take into account anthropogenic factors, as well as circulation processes in the atmosphere for prognostic climate models.

For the spatio-temporal analysis of the active vegetation period climatic parameters variability, a meteorological data array from 6 meteorological stations for the last 20-year period was processed using statistical-analytical and comparative methods. The study is showed an increase in the active vegetation period in 2 days at the Yalutorovsk Station to 7 days at the Pudino Station, when comparing two ten-year periods (2005–2014 and 2015–2024). The average long-term date shift for these stations was 6 days in Spring and 4 days in Autumn. An increase in the sum of active temperatures in the second ten-year period with a maximum increase at the Tomsk Station of +266℃ was noted.

The article discusses the technology of automatically creating and combining vector layers of flood areas based on water level data and a digital terrain model in order to view flooded areas on a geographical map. Special attention is paid to the problems of forming polygons of flood areas from geographical points of flood areas. The program code for creating shape layers from the obtained polygons and combining several shape layers into one shape layer is given.

The analysis of potential hydrological changes and nutrient loading in the basin of the Cheboksary Reservoir in the 21st century is based on future climate projections derived from an ensemble of Coupled Model Intercomparison Project Phase 6 (CMIP6) General Circulation Models (GCMs). These models were selected according to their reliability in reproducing regional climate patterns under two climate change scenarios. The study evaluates the coefficient of variation in annual runoff and the runoff of low-water years with 95% exceedance probability, as well as the total precipitation during the cold season in the Cheboksary Reservoir basin. An approximate assessment of the total nitrogen (N_tot) and total phosphorus (P_tot) loading on the Cheboksary Reservoir was conducted using mathematical modeling based on available observational data from pilot watersheds and projected for the 21st century using data from one GCM.

Based on the materials of MagadanNIRO for 1974–2020, the yield of North Okhotsk herring is considered, depending on the ice conditions. It is shown that the yield of herring generations in the Northern part of the Sea of Okhotsk before 2002 was probably inversely related to the total ice cover of this area in the year of generation. In the subsequent period, this relationship seems to have changed and no longer shows a stable dependence, which is associated with the possible influence of regional responses of the above-mentioned populations and the Sea of Okhotsk ecosystem to the manifestation of climate change. The paper proposes the creation and testing of a new "ice melting index" as well as an index characterizing the ice conditions in the Northeastern part of the Sea of Okhotsk.

This article provides a discussion of the applicability of machine learning methods, with a particular focus on linear regression, to predict the total concentration of TMs in the soil–water ecosystem. Despite the requirement of only minute quantities, TMs have the potential to exert a detrimental effect on the environment. For prediction, seasonal and geographical parameters along with metal concentrations in the soil and their irrigation water were used. A key focus of the study was the normalization of data, a process that has been shown to improve the identification of linear relationships between variables. The developed linear regression model demonstrated a high degree of precision as evidenced by the coefficient of determination 0.9945, the average absolute error of 0.1, and the average percentage error of 5.5%. These findings substantiate the feasibility of employing the proposed methodology to monitor water quality, evaluate pollution risks, and identify potential threats at an early stage in ecosystems that anthropogenic factors have been impacted.

The ongoing process of urbanization significantly affects environmental quality, particularly in the context of global climate change. The Republic of Armenia (RA) is no exception, as urban development continues without strategic planning, leading to adverse impacts on the urban microclimate and reducing resilience to the negative effects of climate change. Drawing on international experience in implementing nature-based solutions (NbS) in urban areas, this study aims to demonstrate their potential, as well as the feasibility and effectiveness as key climate adaptation tools for urban settlements in Armenia using case studies, expert interviews, and policy analysis. However, the effective implementation and advancement of NbS are hindered by limited knowledge and experience, as well as the absence of a strategic approach and an adequate legal framework for their integration into the urban planning process.

The analysis of the surface network of meteorological observations of the Republic of Belarus is given, taking into account the basic requirements and regulations of the World Meteorological Organization, as well as the methodology of the Russian Hydrometeorological Service. The zoning of the territory of the Republic of Belarus was carried out with the allocation of informatively homogeneous meteorological zones and the comparison of the results with the physical and geographical zoning. The information content of each of the homogeneous zones is assessed from the point of view of a multi-element objective analysis of the fields of the main meteorological parameters (air temperature and humidity, precipitation, wind speed, etc.).

Increased turbidity of water in water bodies negatively affects the functioning of aquatic ecosystems and can complicate a number of water use aspects. Heavy metals adsorbed on the surface of bottom soil particles and suspensions increase the total content of pollutants in the water masses during agitation of bottom sediments. The negative effect of heavy metals on aquatic organisms is compounded by the fact that heavy metals are resistant to degradation for many years, they accumulate rapidly in aquatic organisms and are very slowly eliminated from organisms. Currently, hydrodynamic calculations are used to estimate the spread of turbidity fields. Numerical experiments based on a hydrodynamic model make it possible to continuously assess the spread of turbidity fields and calculate the consequences of possible hydraulic engineering measures related to the initiation of increased turbidity in the water area.