Water environment governance performance and its obstacles: a county-level study of the Taihu Lake City cluster

The water environment is a critical component for maintaining ecological balance and supporting the sustainable development of both the economy and society. However, the processes of urbanization and industrialization have led to significant environmental challenges in the Taihu Lake City Cluster (TLCC), including water scarcity and frequent cyanobacterial blooms. To assess the effectiveness of water environment governance at the county level within the TLCC, we developed a comprehensive evaluation index system. This framework was used to analyze the spatiotemporal evolution patterns, examine the interrelationships among governance subsystems, and identify key influencing factors. Our findings reveal that: (1) the performance of water environment governance in the TLCC has exhibited phased improvements, yet significant regional disparities persist. Approximately 91.4% of the counties experienced fluctuating trends in governance performance(e.g.,increase-decrease-increase), while 57.1% were identified as facing governance challenges (e.g., pressure overload). Spatially, a distinct north-south pattern emerged, with higher governance performance concentrated in the southern regions and lower performance in the north. Non-problematic areas were predominantly clustered in the southern part of the TLCC. (2) Six types of decoupling relationships were identified among the subsystems of water environment governance, with weak decoupling emerging as the predominant state, accounting for 47.9%. Anji county, a key area for promoting overall decoupling, exhibited strong decoupling during 67% of the observed period and demonstrated a significant radiation-driven effect. (3)The primary obstacle to effective water environment governance lies within the response (R) subsystem. Major influencing factors include industrial structure, labor intensity, investment in energy conservation and environmental protection, total phosphorus (TP) concentrations, water use intensity, and GDP per capita. The findings provide important policy insights for improving water environment governance across the TLCC region.