Both the insufficiency of water resources and the contamination of even transboundary water bodies are serious problems. Water quality analyses of the transboundary (between Russia and Kazakhstan) Ural River and the Kazakh sector of the Caspian Sea, and their assessment are the main research questions of this study. It is shown that the Ural River is heavily contaminated by polychlorinated biphenyls, heavy metals, oil contaminants, and pesticides, arising from industrial enterprises and agricultural objects. The results show that these toxicants are not only present in water, but they are also accumulated in the muscular tissues of all fish (Abramis brama, Sander lucioperca, Aspius aspius). The Caspian Sea is heavily contaminated by petroleum hydrocarbons due to off shore oil production. A sufficiently high level of accumulation of petroleum hydrocarbons, organochlorine pesticides and heavy metals was determined in the muscles of Caspian fish. All these contaminations lead to the loss of biodiversity and bio-productivity of the Caspian Sea. The authors propose a methodology for a quantitative assessment of the environmental safety level in relation to the Kazakh part of the Caspian Sea, based on bioindication methods. Recommendations, aimed for maintaining acceptable values of water resources quality, are suggested.

In the context of sustainability, the concept of balanced development is crucial at both global and regional levels. This principle is equally significant for specific regions, natural-economic complexes, and local communities. Sustainable regional development necessitates a holistic approach to addressing economic, social, and environmental challenges, which are particularly pertinent at the regional scale. The sustainable development of nations is intrinsically linked to their integration into global processes; however, its resilience and stability are contingent upon balanced regional progress. The West Kazakhstan region exemplifies an economic powerhouse within the country and plays a pivotal role in national regional policy. This study introduces a conceptual model designed to evaluate sustainable development through the balanced interaction of various indicators. The results reveal a disparity between the financial and economic potential of different regions and their environmental challenges. These findings form the foundation for developing a new paradigm of sustainable development that emphasizes the integration of economic growth, social stability, and environmental security. The proposed model has the potential to be adapted in various regions of the world facing similar climatic, water, and social challenges. However, it is necessary to consider local characteristics, data availability, and institutional contexts.

In the context of sustainability, the concept of balanced development is crucial at both global and regional levels. This principle is equally significant for specific regions, natural-economic complexes, and local communities. Sustainable regional development necessitates a holistic approach to addressing economic, social, and environmental challenges, which are particularly pertinent at the regional scale. The sustainable development of nations is intrinsically linked to their integration into global processes; however, its resilience and stability are contingent upon balanced regional progress. The West Kazakhstan region exemplifies an economic powerhouse within the country and plays a pivotal role in national regional policy. This study introduces a conceptual model designed to evaluate sustainable development through the balanced interaction of various indicators. The results reveal a disparity between the financial and economic potential of different regions and their environmental challenges. These findings form the foundation for developing a new paradigm of sustainable development that emphasizes the integration of economic growth, social stability, and environmental security.

Water resources management based on green economy is becoming more and more relevant in the context of changing climate and growing environmental problems. The President of Kazakhstan K.-J. K. Tokayev assigned tasks at the national level to improve the efficiency of use and protection of the country's water resources. Effective strategies for sustainable water management as well as technological innovations are crucial to mitigate the effects of water scarcity worldwide. In addition, financing of green technologies is an important factor. In this study, we analysed the correlation between green finance and sustainable water management outcomes on the example of wastewater treatment in Kazakhstan. The results can be applied in developing strategies to minimise the impact of risks on water, health and environmental infrastructure, as well as in studying the impact of environmental invest-ments. The costs of water supply, precisely the collection, treatment and disposal of waste, pollution elimination activities provide various economic, environmental and social benefits, which makes them a crucial aspect of sustainable development.

Western Kazakhstan is one of the most climate-vulnerable macro-regions in Central Asia. Intensifying aridification, acute water scarcity, and active land degradation are already undermining its ecosystems and an economy built heavily on oil and gas. Yet investment in the region is still driven by short-term priorities rather than a systematic assessment of actual need. A previous study by the authors identified a significant investment gap for sustainable development in the Aktobe region, and showed that this problem calls for comprehensive, comparative analyses rather than a localized one. This study aims to assess and compare investment needs for sustainable development across the four regions of Western Kazakhstan (Aktobe Atyrau, West Kazakhstan, and Mangystau) for 2021–2024, accounting for sustainability thresholds derived from optimal population density. An improved eco-economic methodology was applied, combining per capita investment need calculations with thresholds indicators of regional vulnerability and adaptive capacity, based on official statistical and sectoral data. The results revealed substantial inter-regional differences in investment needs, driven by differing economic specializations, and pointed to an urgent need for targeted investment in water infrastructure modernization, land degradation prevention, and renewable energy development. A new development paradigm is proposed that integrates sustainability thresholds into investment planning, with region-specific recommendations, offering a reproducible framework for arid regions worldwide. The study’s limitations include its short data coverage period (2021–2024), its reliance on official statistics, and the indirect nature of the population-density threshold. The proposed framework was tested for the hydrocarbon-dependent arid regions of Western Kazakhstan.