Policy Synergies for Water Environment Governance in the Yellow River Basin: A Geospatial Perspective

Water environment governance is a complex systemic undertaking that necessitates strengthened synergy of water environment policies across regions to promote high-quality environmental and economic development jointly. This study constructs a water environment governance policy synergy evaluation indicator system from the perspective of policy spatial distribution and regional synergy differences in different geographical regions. Geographically weighted regression and gray correlation analysis methods are used to quantitatively evaluate the policy synergy effect among the nine provinces in the Yellow River Basin. The findings indicate that the synergy effect of water environment governance policies across the nine provinces in the Yellow River Basin is generally positive, though spatial heterogeneity exists. The synergy degree in the basin’s middle reaches is higher than in the upstream and downstream regions. The effectiveness of water environment governance policies is greatly influenced by four dimensions: policy strength, policy objectives, policy measures and policy output. The water quality status indicator, which represents policy output, demonstrates the strongest correlation. While the synergy degree across these four dimensions is high in each province, notable differences remain, with Ningxia and Qinghai provinces exhibiting relatively low synergy degrees across different dimensions. This study provides a basis for basin management authorities to enhance the synergy of water environment governance policies.