Construction of a “Three-Waters” Evaluation Indicator System: A Meta-Analysis

The synergistic management of water resources, the water environment, and the water ecology system (“Three-waters” system) is fundamental to ensuring regional water security and advancing sustainable development. However, existing evaluation indicator systems rely on expert experience and lack quantitative screening criteria, leading to indicator overlap and insufficient representativeness, which restricts the scientificity of management decisions. The study proposes a method integrating meta-analysis with case verification to construct an indicator system. A systematic review of 60 publications (1970–2024) from the Web of Science was conducted and a random effects model was used to merge effect sizes and quantify correlations and heterogeneity between indicators and the “Three-waters” system. The results indicate that the industrial water use proportion (R = −0.77) is the main stress factor in the water resources system, the negative effect of total hardness (R = −0.91) is the most significant in the water environment system, the contribution of the benthic diversity index (R = 0.90) is the most prominent in the water ecology system and vegetation coverage (R = 0.74) exhibits a strong positive effect in the social economic system. The case verification confirms the indicator system established under this method is consistent with the actual situation. This study provides methodological support for system diagnosis, coordinated regulation, and policy formulation, promoting the transformation from single-element to systemic water management.