Multi-objective collaborative governance model for watershed water environment

Due to the conflicting objectives and lack of coordination among multiple stakeholders in watershed management, an integrated model for hydrodynamic-water quality coupling and multi-objective collaborative governance in the Huai River Basin needs to be developed. The model uses the control unit as a carrier, integrating DEM (Digital Elevation Model), land use data, water quality monitoring information, and pollution discharge records to simulate the pollutant transport process and the effectiveness of countermeasures. Furthermore, the NSGA-II algorithm is improved to solve for the Pareto sets corresponding to the four objectives: environment, economy, ecology, and coordination. Validation using main stream data from 2018 to 2024 shows high accuracy in fitting the baseline operating conditions. Results indicate that the environmental priority scheme can optimize the compliance rate from 76% to over 90%. In the collaborative scenario, the government and enterprises share responsibilities more effectively, and the coordination index and satisfaction are also strengthened. Sensitivity analysis can further identify high-load and drought-prone risk sections, providing a basis for differentiated investment and robust governance.