Tetyana Kuchma

Radiological contamination of agricultural landscapes in the Ukrainian Polissia following the Chornobyl accident remains a long-term driver of spatially uneven ecological and food-security risks, despite a general reduction in average dose rates observed over the past decades. The issue has gained renewed relevance under war-related pressures, when land-use regimes are disrupted, monitoring infrastructure is damaged or inaccessible, and decision-makers require rapid spatial assessments without continuous field measurements. In this context, spatial planning emerges as a critical component of crisis environmental management, enabling the integration of environmental, logistical and social constraints into land-use prioritization. This study aims to evaluate the potential of spatial planning of radiologically contaminated lands as a decision-support instrument in crisis environmental management, by integrating open geospatial data, dose estimates, landscape vulnerability parameters, and indicators of anthropogenic pressure. The methodological framework was developed and tested in 2024–2025 at the Institute of Agroecology and Environmental Management (NAAS, Kyiv). The approach combines open-access radiological maps of 137Cs, population dose estimates, and land-cover information with Shuttle Radar Topography Mission elevation data and ESA WorldCover satellite products. All inputs were aggregated into a composite Radioecological Criticality Index (RECI), designed to prioritize territories at regional, oblast, and local scales. A pilot assessment was conducted north of Rozsokhivske (Zhytomyr region), with subsequent scaling to oblast-level and regional-level cartography across the broader Polissia. The results demonstrate that the majority of analyzed territories currently fall into low-critical or moderately critical classes, reflecting long-term radioactive decay, land-use shifts, and attenuation processes in soils. Nevertheless, stable clusters of high and very high criticality persist, particularly in river floodplains, poorly drained forest complexes and micro-depressions where surface runoff accumulates. These «criticality nodes» are strongly associated with elevated 137Cs levels, hydromorphic soils, and intensified biological uptake, which sustain prolonged radionuclide circulation in the soil–plant system. A comparison with existing Ukrainian radioecological maps indicates spatial compatibility in identifying high-risk zones, while the RECI-based approach provides finer territorial differentiation due to its broader parameter base, which includes landscape morphology, hydrological distance, exploitation intensity, and population dose as integral risk indicators. Importantly, the method allows risk-oriented zoning and scenario-based land-use planning without the need for new field sampling, making it practical under wartime constraints. The research confirms that RECI can serve as a functional planning tool for crisis environmental management, particularly for prioritizing remediation actions, restricting agricultural production in high-risk areas, limiting forest biomass exploitation, supporting food-safety monitoring, and developing recovery strategies for degraded agroecosystems. The resulting spatial products can inform regional policy, sustainable food-security planning, and long-term rehabilitation of territories affected simultaneously by chronic radiological stress and wartime disturbance.

For the southern regions of Ukraine, in particular Kherson, Zaporizhzhia, and Dnipropetrovsk regions, Kakhovka Reservoir played a key role in providing water resources. Its operation was critically important for the stable water supply of the agricultural sector through an extensive network of irrigation systems, supporting industrial production, meeting the needs of local communities, and preserving ecosystems, including the Dnipro Delta and floodplain areas. The total irrigated area in Kherson, Zaporizhzhia, and Dnipropetrovsk regions reached 584,000 hectares, while the planned area exceeded 900,000 hectares. The demolition of Kakhovka Hydropower Plant on June 6, 2023, caused one of the largest environmental disasters in the history of Ukraine, resulting in the loss of 18 km3 of freshwater and the destruction of irrigation systems over an area exceeding 584 thousand hectares. Thus, the destruction of Kakhovka HPP dam caused systemic destabilization of the country’s food security and the regional agricultural economy. A comprehensive assessment of the consequences of this environmental crisis covers several key areas: the formation of new agroclimatic conditions in the steppe zone, increased risks of soil degradation and desertification, threats to the socio-economic stability of the region, and the need to develop new models for agricultural adaptation. The aim of this study is to assess the spatial and temporal changes in the state of agricultural resources in Dnipropetrovsk, Zaporizhzhia, and Kherson regions resulting from the drainage of Kakhovka Reservoir during the period 2020–2025 using Earth remote sensing data. For a comprehensive assessment of transformations in vegetation cover and the water regime of agricultural landscapes, four spectral indices were applied: NDVI, SAVI, NDWI, and NMDI. The analysis was conducted using Google Earth Engine, QGIS, Copernicus Open Access Hub, and Sentinel Hub EO Browser platforms. Agricultural lands within 50 km of the former reservoir were examined and compared with more distant areas. The results confirmed a sharp decline in vegetation activity after June 2023, which was statistically verified using t-tests and the Mann–Whitney test. The most significant changes were recorded in Kherson region: NDVI decreased by 55%, SAVI by 57%, NDWI by 88%, and NMDI by 44%. In Zaporizhzhia region, the decline ranged from 25% to 38%, while in Dnipropetrovsk region it ranged from 26% to 30%. The analysis of the indices revealed a substantial increase in areas affected by extreme drought, particularly in Kherson region. The use of satellite data is an effective tool for studying transformations of vegetation cover and water regime conditions resulting from the destruction of Kakhovka Reservoir and climate change. The obtained results are relevant for the development of national and regional irrigation restoration programs and measures for adapting agricultural production to climate change based on the principles of reducing greenhouse gas emissions in agricultural production, achieving a balance between soil degradation and restoration, and forming bioenergy lowcarbon agroecosystems.

Based on criteria that consider both natural and anthropogenic factors affecting the radioecological situation in the region, the components of a radio­ ecological-landscape map of the Ukrainian Polissia have been developed. The main elements of the map include: radiological indicators (soil contamination density by radionuclides), landscape features (soiltypes, vegetation cover, relief), as well as climatic and hydrological conditions. This approach enables a com­prehensive assessment of ecological risks and deter­mines the most appropriate directions for land use in agriculture and forestry. Taking into account the components of the integrated radioecological-landscape map of the Ukrainian Polissia, a comprehensive index of the radioecological criticality of territories has been developed. This index is calculated based on a set of coefficients that reflect the map components and their analysis. It has been established that integrating existing databases with targeted additional studies is the optimal approach for forming an effective ra­dioecological criticality index. This will ensure more reliable risk assessments and support the development of radioecological safety management strategies at different levels. The necessity of integrating various data sets, including local and global resources, to form a comprehensive approach to assessing radioecologi­cal criticality is substantiated. This approach allows for consideration of both local territorial features and broader geographic trends. In particular, the use of data on river networks, relief, and soil types improves the accuracy of modeling radioecological processes, such as radionuclide migration. The radioecological-landscape map enables adequate assessment of both current and forecasted radioecological conditions, as well as prompt development of response systems aimed at improving the situation, selecting relevant solutions to socio-economic and environmental issues in the region, and justifying the implementation of appropriate measures in the mapped locations

Climate change, accompanied by anomalously high temperatures and a decrease in precipitation during the warm season, can have serious consequences for the ecosystems and sustainability of the Ukrainian Polissia. In particular, there are increased risks of forest and peat fires, as well as an overall deterioration of the region’s ecological condition. Between 1990 and 2021, the Ukrainian Polissia region recorded an average temperature increase of 0.60 °C per decade, along with a 3–5% decrease in annual precipitation. An analysis of the spatial distribution of wildfire incident density based on satellite data (FIRMS) in the regions of the Ukrainian Polissia from 2001 to 2023 highlighted several periods of sharp increases in fires: 2002, 2007–2009, 2014–2015, and 2019–2020. The Spring Fire Season and the Late Summer–Autumn Fire Season coincide with periods of reduced precipitation, which in some years reached 40–60% below the climatic norm. Although the climatic conditions of spring 2022 were not as warm and dry as those in 2020, significant parts of Kyiv Polissia and Chernihiv Polissia suffered from large-scale wildfires due to ongoing military actions. The spatial distribution of fire frequency in 2020 and 2022 highlights different contributing factors: in 2020, weather anomalies were the primary cause, while in 2022, armed hostilities played a key role. Military conflicts not only increase the risk of fires but also complicate firefighting efforts, making the region even more vulnerable to large-scale forest fires, and thereby threatening its sustainability. These findings underscore the urgent need for integrated fire management strategies that take into account climate change, land-use policies, and geopolitical factors to mitigate the escalating wildfire threat in the region and ensure long-term sustainability.

Aim. To determine the patterns of the climate change impact on the transformation of agricultural production and the ecosystem of Ukrainian Polissia in terms of time and space. Methods. Satellite and statistical data for the last 40 years (1982–2022) were used. The mean temperature for the vegetation period was defined by the sum of radiation temperatures of the terrestrial surface, calculated using the data of the infrared range (10.3–11.3; 11.4–12.4 μm) of the high-precision AVHRR radiometer of artificial meteorological Earth's satellites, NOAA, and the precipitation dynamics – using the data of ERA5 ECMWF/Copernicus Climate Change Service. The impact of climate change on the vegetation state and phenological parameters, including the beginning, end, and duration of the vegetation season, was determined by the normalized difference vegetation index (NDVI), obtained using the data of the infrared (0.72–1.1 μm) and red (0.58–0.68 μm) ranges of the AVHRR radiometer on the website of STAR NESDIS NOAA. Crop yields and the dynamics of sown areas were determined by the data from the State Statistics Service of Ukraine. The information about the dynamics of the forest cover was obtained using the Global Forest Watch satellite data. To evaluate the impact of climate change on Ukraine's forests, the investigation was conducted on burnt forest areas, using the MCD64A1 6.1 index, developed on the basis of the MODIS satellite data. Results. According to the satellite data, the radiation temperature of the terrestrial surface during the growing period increased by 2.2 ºС on average in the territory of Ukrainian Polissia over the last 40 years. There is a regional difference in the temperature regime observed in the direction from west to east. In the territory of western Polissia, the increase in the temperature of the terrestrial surface in recent decades was within the range of 1.2–1.6, and in the central and eastern parts – within 2.3–2.9 ºС. Due to the warming, the duration of the growing period was extended by 21–35 days, mostly because of earlier spring onset. There is a descending trend in the average annual precipitation amount down to 20–30 mm, which is especially notable for central and eastern Polissia. The warming was the reason for the introduction of the crops, new for this region, into the structure of sown areas, especially corn and sunflower, which had a generally positive effect on the vegetation state by the NDVI index, which increased from 0.30 in 1982–1992 to 0.36 in 2012–2022 on average. The crop yield increased accordingly, and according to the statistical data for the recent years, amounted to: corn – 7.0–9.5 t/ha, winter wheat – 4.5–5.0, and sunflower – 1.5–2.0 t/ha, which is close to the level of their yield on chornozem. At the same time, due to climate change and the transformation of agricultural activity, there has been a higher risk of deterioration in the ecological state of typical Polissia landscapes, droughts, and soil degradation. According to the results of the analysis of twenty-two years of the dynamics in forest fires, the largest areas of burnt forests were registered in 2012 (694.30 sq.km), 2015 (1,078.81 sq.km), and 2020 (776.27 sq.km), which demonstrated the increase in fires during the recent decade along with the tendency towards longer fire hazard period. Conclusions. The increase in the temperature of the terrestrial surface of the Ukrainian Polissia during the growing period and the lengthening of the growing period created the conditions for corn and sunflower to be introduced into the arable areas, which had a positive impact on the vegetation state index, NDVI. As a result of these transformations both in the sown area of these crops and their yield, Polissia is becoming a new grain-oil belt of Ukraine. Concurrently, there are higher risks associated with maintaining high performance of agroecosystems and the increase in the risks for soil degradation processes, the deterioration of the ecological state of wetlands and forests, as well as drying-out of small rivers and lakes. Balancing the high yield of modern agroecosystems and safe nature management requires systemic measures in adapting the agricultural activity and nature management to new climatic conditions, which requires implementing the management of soil, water, and bio-resources, achieving optimal parameters of fertility for mineral and peaty-swampy soils. Reconstructing current land reclamation systems to optimize water regimes for the agricultural lands and protect typical Polissia ecosystem is needed.

The article provides a comprehensive analysis of the interaction between deforestation and climate change, with particular emphasis on the impact of military actions on the reduction of forest ecosystems. The research utilized general scientific methods (data analysis and synthesis), retrospective and comparative analysis, analytical-synthetic methods (study of scientific and statistical data, archival materials, etc.), and remote sensing techniques. The aim of the study was to identify the main causes of the reduction in forested areas in Ukraine and their role in the context of global climate change, as well as their significance for the socio-economic development of the country during wartime and the post-war period. The role of forest ecosystems as a source of a wide range of ecosystem services and as a significant component of the socio-economic status of the Ukrainian Polissya region is analyzed. Special attention is given to the interaction between the reduction of forest-covered areas and the intensification of climate change. The main factors contributing to the reduction of Ukraine’s forest ecosystems are presented, with a particular focus on forest fires, including those caused by military actions. It was established that from April 2023 to April 2024, the highest number of forest fires occurred in the eastern and southern parts of the country, where active military actions are ongoing. An automated methodology for decoding satellite images to detect areas of Scots pine dieback due to infestation by the pine shoot beetle was developed, resulting in a map of the study area showing the boundaries of forestry districts, the grid of forest compartments, the contours of damaged forest areas, and new dieback hotspots. The study demonstrates that forest ecosystems are essential for mitigating climate change and ensuring sustainable regional development. This is particularly true for the Ukrainian Polissya region, especially Zhytomyr Oblast, which has the highest forest cover in the country but also leads in the loss of forest-covered areas.

У статті висвітлено природно-кліматичні та соціально-економічні ретроспективні передумови повернення в сільгоспвикористання виведених з обігу радіоактивно забруд- нених земель Полісся України. Доведено необхідність застосування сучасних методів та засобів радіоекологічних досліджень із метою оцінки радіоекологічного стану угідь для наступного розроблення планових управлінських документів стратегічного характеру. В дослідженні, виконаному в Інституті агроекології і природокористування НААН упродовж 2020–2023 рр., використовували загальнонаукові методи (аналіз та синтез), ретроспективний і порівняльний аналіз, аналітико-синтетичний (вивчення наукових і статистичних даних, законодавчих та установчих документів тощо) й математикостатистичний методи. Аналіз соціально-економічної ситуації здійснювали на основі офіційних статистичних даних головних управлінь статистики у Волинській, Жито- мирській, Київській, Рівненській та Чернігівській обл. Розрахункові рівні радіонуклідного забруднення території отримували на основі офіційних даних ДУ «Держгрунтохорона». Радіоекологічно-ландшафтне картування реалізовували у відкритому безкоштовному програмному забезпеченні QGIS. Показано, що ґрунтові характеристики й особливості рослинного покриву Українського Полісся сприяють забрудненню радіонуклідами сіль- ськогосподарської та лісової продукції. Кліматичні зміни та наслідки російської воєнної агресії є істотними модифікувальними чинниками для всіх наявних раніше екологічних і соціально-економічних викликів у регіоні. Це вимагає реалізації комплексних заходів із реабілітації регіону, яким мають передувати моніторингові дослідження та розроблення відповідних планових документів стратегічного характеру. За результатами ретроспективного аналізу та розрахунків встановлено, що за умови проведення рекомендованих агрозаходів відновлення ефективного аграрного виробництва можливе практично на всій території Українського Полісся. Розроблено метод комплексного радіоекологічноландшафтного картування радіоактивно забруднених земель Українського Полісся, який передбачає ландшафтний підхід з інтегруванням даних низки тематичних карт.

For a certain time since the beginning of the aggression of the Russian Federation in Ukraine, education in many Ukrainian universities has been suspended due to security reasons. Ffurther adaptation of the educational process within the Ecology program to the conditions of war included, inter alia, the integration in educational courses the research methodology, and environmental impact assessment of hostilities. The impact of the military actions on the environment in general and the atmosphere, in particular, was in the focus of the discussions during the course Climatology and Meteorology. Researchers and students analyzed powerful direct and indirect effects, namely due to changes in the optical characteristics of the atmosphere, atmospheric pollution as a result of the emission of products of detonation of missiles and shells and increasing emission of greenhouse gases and gas-aerosol impurities. Satellite data were used for this purpose.Satellite observation of atmospheric concentrations of formaldehyde, aerosol, carbon monoxide, nitrogen oxide, and sulphur dioxide from the Sentinel-5P satellite was an important research method integrated into the educational process. Daily satellite observation data were analyzed using the Google Earth Engine platform for the period 2019-2022. Data were monthly and yearly averaged within the boundaries of rayons (second-level administrative units of Ukraine). In addition, shelling incidents data from the Armed Conflict Location & Event Data Project (ACLED) were analyzed. It helped to register dynamic of the air pollution in the conditions of war.A full-scale war in Ukraine caused the suspension of many enterprises that were the main sources of gas emissions into the atmosphere, especially in the eastern and southern parts of Ukraine. Therefore, in recent months, the content of pollutants in the atmosphere over these regions is mainly tent to background values and as a result of hostilities. However, massive shelling, the use of military heavy equipment, and fires caused additional emissions of a number of pollutants into the atmosphere. It should be noted that in certain regions and certain months during the active phase of hostilities, these emissions were exceeded by several times compared to the average for the period 2019-2021.

The effect of nighttime lighting on the anatomical and morphological structure and the content of photosynthetic pigments in the leaves of Tilia cordata, Aesculus hippocastanum, and Platanus acerifolia was estimated on the example of garden-park and street plantings of Kyiv. At the experimental sites, the level of illumination and the soil surface temperature during the day and night periods were examined. The anatomical and morphological structure of the leaves was studied using transmission electron microscopy. The content of photosynthetic pigments (chlorophylls and carotenoids) in tree leaves was determined spectrophotometrically.The analysis of variance revealed that nighttime lighting significantly affected the anatomical structure and the content of photosynthetic pigments in the leaves of T. cordata and P. acerifolia. In A. hippocastanum, only parameters of stomata and palisade parenchyma showed a significant reaction to this stress factor. Досліджено вплив штучного нічного освітлення на анатомо-морфологічну структуру та вміст фотосинтетичних пігментів в листках насаджень Tilia cordata, Aesculus hippocastanum і Platanus acerifolia на прикладі садово-паркових і вуличних насаджень Києва. На дослідних ділянках реєстрували рівень освітленості, температуру на поверхні ґрунту в денний та нічний періоди. Анатомо-морфологічну структуру листків досліджували за допомогою трансмісійного електронного мікроскопу. Вміст фотосинтетичних пігментів (хлорофілів і каротиноїдів) у листках дерев визначали спектрофотометрично.Результати дисперсійного аналізу показали, що нічне освітлення суттєво впливає на анатомо-морфологічну структуру, а також вміст фотосинтетичних пігментів у листках T. cordata і P. acerifolia. Водночас, в A. hippocastanum лише морфологічні показники продихів і палісадної паренхіми виявили істотну залежність від цього стресового фактору.