Study on sustainable utilization of water resources in China based on mechanical balance model

Accurate assessment of the sustainable utilization levels of water resources and the coordination between elements is a prerequisite for mitigating growing human-water conflicts.Based on the PSR indicator framework, a comprehensive index and a mechanistic equilibrium model are adopted to measure the sustainable utilization level and coordinated development status of water resources systems in provinces and municipalities in China in 2011 and 2019.The results show that:(1) More than half of the provinces and municipalities in China are 'unsustainable' or 'weakly sustainable' in terms of water resources utilization, and the overall sustainable utilization level is relatively low.(2) In terms of coordination types, the majority of provinces and municipalities are of the coordination type or basic coordination type, but the proportion of coordination type is decreased while the proportion of basic coordination or dysfunctional type is increased.(3) Deviation degree is predominantly distributed between quadrant Ⅰ and quadrant Ⅲ provinces and municipalities.Natural state is the main constraint for quadrant Ⅰ provinces and municipalities.Quadrant Ⅲ is constrained by both water stress and conservation response.(4) Based on the prominence of the problems, the provinces and municipalities are classified into three problem types and corresponding improvement measures are proposed.These results can provide scientific reference for improving the sustainable utilization of regional water resources.