Evolutionary Dynamics and Mechanisms of Tripartite Synergistic Development in Hydropower Resettlement

Under tightening land, fiscal, and environmental constraints, hydropower resettlement must shift from a compensation-oriented model toward synergistic development. Existing studies fail to clearly define the boundary between statutory responsibilities and incremental synergistic action, and lack a tripartite quantitative framework capturing the closed-loop interaction among hydropower enterprises, local governments, and resettled households. This study contributes to the literature by explicitly conceptualizing synergistic development as incremental collaboration beyond statutory responsibilities, and constructing a tripartite evolutionary game model with a gradient strategy space from routine compliance to active collaboration. The model incorporates key parameters like additional collaboration costs and synergy premium, and uses replicator dynamics to identify equilibrium regimes and threshold conditions. The results show that reasonable cost–benefit structures enable convergence to a full synergistic equilibrium, while excessive additional collaboration costs lead to low-level compliance lock-in; strategy-dependence coefficients only affect convergence speed, not the long-term evolutionary tendency toward synergy. The findings provide a quantitative basis for designing incentive-compatible resettlement governance mechanisms.