Abstract:

[Objective] This study focuses on the Yangtze River Economic Belt and constructs a water resources carrying capacity evaluation system that covers four subsystems: water resources, society, economy and ecological environment. The aim is to reveal the current status and future development trend of water resources carrying capacity in the Yangtze River Economic Belt, and to provide a scientific basis and decision-making reference for the rational planning and utilization of water resources, the adjustment and optimization of industrial structure, and ecological environment protection within the region. [Methods] The spatiotemporal evolution characteristics of water resources carrying capacity in the Yangtze River Economic Belt from 2012 to 2021 were analyzed using the TOPSIS method and the standard deviation ellipse method. Combined with the coupling coordination degree model, the coordinated development level among the subsystems within the water resources carrying capacity system was further investigated. To better understand the future development trend of water resources carrying capacity, the grey prediction model was applied to predict its trend over the next five years. [Results] The study revealed the dynamic changes in water resources carrying capacity in the Yangtze River Economic Belt during the study period, along with its spatial distribution characteristics and evolution trends. Between 2012 and 2021, the water resources carrying capacity showed an overall fluctuating upward trend, gradually improving from an alert state to a good state, indicating a significant enhancement in the region’s water resources carrying capacity. Spatially, the center of water resources carrying capacity shifted southwestward toward areas with relatively lower capacity, which may be related to regional economic development patterns, industrial restructuring, and differences in water use efficiency. Regarding system coupling and coordination, except for 2012, the coupling degree between subsystems reached a high coupling stage, and the coupling coordination evaluation gradually shifted from near disorder to good coordination, demonstrating continuously improving coordinated development and enhanced synergy among the subsystems. Analysis of influencing factors identified the proportion of tertiary industry, urbanization rate, and per capita daily domestic water consumption as the three factors most strongly correlated with water resources carrying capacity. Changes in these factors significantly affected its increase or decrease. The water resources carrying capacity was projected to show a positive development trend over the next five years. [Conclusions] It is recommended that the upstream areas develop water-saving irrigation, control fertilizer usage, and enhance urbanization levels; the midstream areas develop reclaimed water use, strengthen sewage treatment, and accelerate industrial transformation; and the downstream areas control population growth, promote water conservation and environmental protection, restore ecosystems, and increase forest coverage. The research findings provide a valuable scientific basis for the efficient management and utilization of water resources in the Yangtze River Economic Belt,as well as for promoting the coordinated development of the regional economy and society,and for achieving sustainable development goals in the region.

Key words: water resources carrying capacity, entropy weights-CRITIC-TOPSIS Model, coupling coordination, degree of relevance, GM(1,1) model, Yangtze River Economic Belt