A novel composite cloud model-based three-stage evaluation for the spatial equilibrium of water resources in China

The mismatch between water resource conditions and economic and social layout leads to spatial imbalance of water resources, which restricts China's socio-economic development. To quantitatively study the spatial equilibrium of water resources in China, this article proposed a three-stage hybrid model comprising regional assessment, spatiotemporal pattern analysis, and source apportionment. By adopting this approach, the study calculated the SEIWR (Spatial equilibrium index of water resources) and a comprehensive evaluation of the spatial balance level of water resources in China can be conducted. The results showed that (1) from 2008 to 2021, the SEIWR in mainland China had improved as a whole, but the level in Liaoning, Chongqing and other provinces and cities had declined; (2) in China, the SEIWR exhibited a distinct geographic pattern with high levels observed in the eastern and southern regions, while low levels were observed in the western and northern regions. The gap between the east and the west gradually narrowed during the study period. (3) There were zones with obvious differences, showing a certain spatial positive correlation aggregation effect. The central and eastern regions showed a large area of high-high cluster spatial patterns. (4) The SEIWR in East China, South China, and North China was greatly influenced by economic and social indicators. The SEIWR in Northeast and Central China was strongly influenced by ecological environmental indicators, while the SEIWR in Southwest and Northwest China was more influenced by water system indicators. (5) In China, the ecological environment was strongly influenced by economic and social conditions. The above research results help decision-makers understand the SEIWR in different regions and the key factors that affect such level, which help them develop measures tailored to local conditions so that all regions can improve their SEIWR.