Over the past 70 years, Central Asia has emerged as a globally recognized water security hotspot due to its unique geographic location and uneven distribution of water resources. In arid and semi-arid regions, understanding runoff dynamics under climate change is essential for ensuring regional water security. This study addresses the data-sparse Central Asian region by applying the ISIMIP3b multi-scenario analysis framework, selecting three representative global hydrological models. Using model intercomparison, trend analysis, and geographically weighted regression, we assess the spatiotemporal evolution of runoff from 1950 to 2080 and investigate the spatial heterogeneity of runoff responses to precipitation and temperature. The results show that under the historical scenario, all models consistently identify similar spatial pattern of runoff, with higher values in southeastern mountainous regions and lower values in western and central regions. However, substantial differences exist in runoff magnitude, with regional annual means of 10, 26, and 68 mm across the three models, respectively. The spatial disparity of runoff distribution is projected to increase under higher SSP scenarios. During the historical period, most of Central Asia experienced a slight decreasing trend in runoff, but the overall trends were −0.022, 0.1, and 0.065 mm/year, respectively. In contrast, future projections indicate a transition to increasing trends, particularly in eastern regions, where trend magnitudes and statistical significance are notably greater than in the west. Meanwhile, the spatial extent of significant trends expands under high-emission scenarios. Precipitation exerts a positive influence on runoff in over 80% of the region, while temperature impacts exhibit strong spatial variability. In the WaterGAP2-2e and MIROC-INTEG-LAND models, temperature has a positive effect on runoff in glaciated plateau regions, likely due to enhanced snow and glacier melt under warming conditions. This study presents a multi-model framework for characterizing climate–runoff interactions in data-scarce and environmentally sensitive regions, offering insights for water resource management in Central Asia.

The scientific article is aimed at substantiating the classification of hydraulic jet pumping units, developing an experimental model of an improved hydraulic jet pumping unit, conducting experimental studies - determining the useful flow Qгн depending on the flow rate of the centrifugal pump used Qн for two variants of the pumping unit operating according to the traditional and alternative technology of water lifting, determination of the head losses hснi and friction coefficients ξснi in jet pumps, increasing the ejection coefficient Ke from the swirl parameter S of water supply to the intake chamber of the jet pump and laboratory tests of the hydraulic jet pumping unit for agricultural water supply and irrigation of pastures. The results of experimental studies and laboratory tests of an experimental model of an improved water-jet pumping unit, developed at NAO KazNAU, are presented. An analysis is given of the results of comparative tests of a hydraulic jet pumping unit for two variants of the technological process: an alternative and a traditional one with an increase in the effective supply of an alternative option by 2-4 times, a decrease in the required pressure by 1.5-2 times and an increase in efficiency by 1.1-2 times. The aim of the study is to obtain results to substantiate the classification of hydraulic jet pumping units, to carry out experimental studies and laboratory tests of an improved hydraulic jet pumping unit operating according to an alternative water lifting technology, which allows to reduce the required head of the pumping unit, increase the useful flow and increase the efficiency of the improved hydraulic jet pumping unit. The work used patent research with a review of works that were carried out according to existing methods: identifying close analogues, analyzing existing works and using them in development. Experimental studies were carried out to study the technological process of water rise from wells, the processes occurring in the used jet pumps - determining the useful flow depending on the flow of a centrifugal pump, determining the pressure losses and friction coefficients in jet pumps, the ejection coefficient and checking the reliability of the theoretical assumptions obtained. Based on the analysis of the work performed and patent research on technologies for lifting water from underground water sources by hydraulic jet pumping units and designs developed for them, a substantiated classification of hydraulic jet pumping units is proposed, which allows, depending on the task at hand, to correctly choose the necessary structural and technological scheme, type of jet pump and its implementation in the development of the required effective standard sizes of the hydraulic jet pumping unit. The scheme of the test bench and the experimental model of the improved hydraulic jet pumping unit with measuring equipment and instruments for conducting experimental research and laboratory tests on a bench well is presented.

Based on long-term informational and analytical materials of the World Meteorological Organization (WMO), the Weather and Climate reference portal and stationary meteorological stations of the RSE Kazhydromet located in the catchments of the Ili River basin, which cover the Almaty region (Narynkol, Tekes, Sumbe, Dobyn, Aydarly, Kapshagay, Usharal, Bakanas, Kokzhide, Kuigan) of the Republic of Kazakhstan, Xinjiang Uygur Autonomous Region (Tekes, Xinyuan, Tokkuztara, Yamata, Kuldzh) of the People’s Republic of China and using the law of geographic vertical zoning, the energy resources of river basins and groundwater, the climatic potential of natural systems that characterize the heat and moisture supply of natural landscapes and ecological and hydrogeochemical indicators showing the direction and intensity of the hydrogeochemical process on a spatial scale, which allowed for geomorphological zoning, are determined catchments of the Ili river basin, characterizing the natural functions of the river basin, to have runoff and environment formation, which are the basis for environmental management and environmental engineering.

Background and significance. The effective management of irrigated agricultural land in arid areas depends on timely spatial information on crop condition and economic performance at the level of individual cadastral parcels. In practice, conventional land administration systems usually do not contain such operational data. As a result, decisions on irrigation scheduling, fertiliser application, and land reclamation are often made uniformly across fields, despite substantial spatial differences in land quality and productivity. This reduces both agronomic and economic efficiency. Methods. The study combined Sentinel-2 satellite imagery with digital cadastral boundaries to evaluate irrigated farmland in the Saryagash district of Turkestan Region, Kazakhstan, during 2023–2024. NDVI values were derived from Sentinel-2 imagery acquired on 14 June 2024 under cloud cover below 5 %, using bands B8 and B4 with a spatial resolution of 10 m. The processing and spatial analysis were carried out in QGIS 3.28. Two composite indicators were applied across ten irrigated farms with a total area of 371 ha. The Estimated Sowing Potential Coefficient (ESBK) was used to characterise land suitability by integrating soil quality, moisture availability, and salinity risk. The Farm Decision Efficiency Index (FDEI) was used to assess the economic viability of production by comparing gross revenue with total production costs per hectare; values above 1.0 indicate profitable farming. Results. The analysis showed considerable spatial variation among the studied farms. NDVI values ranged from 0.36 to 0.82. Two farms were identified as priority areas for reclamation, with ESBK values of 0.11–0.13, while three farms demonstrated relatively high land potential, with ESBK values of 0.50 and above. Farms with NDVI values of at least 0.70 consistently showed stronger economic performance, with FDEI values between 1.47 and 1.60 and net profits of 400–560 thousand KZT per hectare.