This study aims to achieve coordination between regional economic development and ecological environmental protection and to mitigate issues such as competition for water use among industries and significant disparities between water supply and demand. A multi-water-source, multi-user, and multi-objective optimal water resource allocation model was developed for Ordos City using general water allocation and simulation (GWAS). This model was applied to optimize water resource allocation on a monthly scale for various users across different administrative units (banners) in both short- and long-term planning periods. The results indicate that Ordos City’s allocated water volume for 2025 and 2030 is projected to be 1833.36 × 10⁶ m³ and 1963.44 × 10⁶ m³, respectively, with an overall water shortage rate of 5.46% and 5.67%, respectively. Water shortages are predicted in Dongsheng District, Dalad Banner, Etuoke Banner, Hangjin Banner, and Wushen Banner, primarily during the agricultural water usage period from March to November. The regional water supply structure was notably optimized, with a gradual decrease in the proportion of groundwater in the total water supply and a corresponding increase in the supply of surface water and unconventional water. These changes effectively improve local groundwater overexploitation and enhance the water supply efficiency. The research findings could offer valuable theoretical and technical support for the development and utilization of water resources, as well as for adjustments in the population–economic–industrial structure of Ordos City. Additionally, this study could provide scientific references for optimizing water resource allocation in other water-deficient cities in arid and semi-arid areas of the Yellow River Basin.

Climate change and anthropogenic activities have increased the complexity of hydrology–soil–vegetation interactions in arid-region irrigation areas. Therefore, studies on the spatiotemporal characteristics of these interactions can greatly benefit the sustainable development of arid areas. This study developed a spatially granular dataset of the key hydrology, soil, and vegetation elements for the Hetao Irrigation District (HID) for 2000–2020, recognized as the largest single-port artesian irrigation area in Asia, and explored the interactions between these elements by means of a geodetector, the analytic hierarchy process, and the Pearson correlation coefficient. The key results indicated the following: (1) a declining trend of 0.1–0.15 in the comprehensive influence of hydrology–soil–vegetation interactions; increasing significance of hydrologically driven soil and vegetation evolution, with feedback between soil and vegetation; (2) the maximization of the interactions between soil moisture and precipitation and groundwater, with evapotranspiration as the dominant factor regulating hydrology–vegetation interactions; (3) the interactions between hydrology, soil, and vegetation showing nonlinear synergism; (4) and the spatial distributions of the hydrology–soil–vegetation interactions showing significant band-like patterns with weak coupling between the elements.

The Kubuqi Desert, China’s seventh-largest desert, is characterized by a severe water supply–demand imbalance and ecological fragility. This study conducted a multi-dimensional dynamic evaluation of the water resources carrying capacity (WRCC) of the desert and its subordinate banners using the TOPSIS model with game theory-based combined weighting. The main obstacle factors were subsequently identified via the obstacle degree model. The results indicated that the comprehensive WRCC index increased from 0.351 in 2010 to 0.584 in 2023, showing a stepwise upward trend. The WRCC grade gradually shifted from Grade II in 2010 to Grade III in 2023. The ecological environment and socioeconomic conditions subsystems improved most markedly, with their contributions to the comprehensive WRCC increasing year by year. The water resources subsystem fluctuated within a narrow range and remained largely at Grade III. The WRCC of each banner exhibited significant spatiotemporal heterogeneity, forming a spatial pattern of “high in the east and low in the west”. WRCC values were ranked in descending order as Jungar Banner, Dalad Banner, and Hangjin Banner, with multi-year averages of 0.541, 0.516, and 0.492, respectively. From 2010 to 2014, all banners except Jungar Banner remained in an overloaded state for most years. Since 2015, the carrying status of each banner has generally improved alongside rising WRCC, and the entire region has reached a critically bearable state. The main obstacle factors constraining WRCC included the ecological water use rate, soil erosion rate, water supply modulus, aridity index, water conservancy and environmental investment rate, water resources exploitation rate, water quality compliance rate in water function zones, water use per 10⁴ CNY GDP, and forest coverage rate. Among these, three belonged to the water resources subsystem, four to the ecological environment subsystem, and two to the socioeconomic conditions subsystem, indicating that socioeconomic indicators exerted the weakest restrictive effect on WRCC. Future WRCC development and governance should adhere to the rigid constraints of water resources, prioritize the optimization of the industrial structure and urban layout, implement targeted soil erosion control, and steadily increase forest coverage, thereby promoting the green, low-carbon, and efficient development of the Kubuqi Desert.

To alleviate the severe supply–demand imbalance and promote coordinated socioeconomic and ecological development in the Kuye River Basin of Inner Mongolia, this study constructed an optimal water resources allocation model based on the General Water Allocation and Simulation (GWAS) model. With 2023 as the base year, monthly-scale optimal allocation of water resources was conducted for both the short-term planning year (2030) and the long-term planning year (2035), and appropriate development scales were proposed in accordance with the “Four Waters and Four Determinations” principle. The results indicated that the total volume of optimally allocated water was 195.25 × 10⁶ m³ in 2030 and 207.41 × 10⁶ m³ in 2035, with overall deficit rates of 3.63% and 5.02%, respectively. Deficits occurred during the agricultural irrigation season from March to November and were mainly concentrated from May to September. The water supply structure was markedly optimized in both planning years. The surface water share rose from 13.28% to 14.03%; the unconventional source share rose from 47.50% to 52.13%; and the groundwater share dropped from 39.22% to 33.84%. In terms of water allocation, industrial allocation rose steadily while agricultural allocation decreased from 13.52% in 2030 to 10.22% in 2035, as water consumption shifted toward high-benefit, water-efficient sectors such as industry and domestic use. Under the “Four Waters and Four Determinations” policy, the agricultural irrigation area that could support sustainable development was calculated at 15.93 × 10⁴ mu in 2030 and 15.07 × 10⁴ mu in 2035. The development scales of urban construction, population agglomeration, industry, and services were also estimated. These results provide a quantitative basis for green, high-quality development under rigid water constraints in the Kuye River Basin. They also offer an important reference for other arid and semi-arid regions seeking to optimize water allocation and implement the “Four Waters and Four Determinations” policy.