A Game Theory-Based Approach for Exploring Water Resource Exploitation Behavior in the Poyang Lake Basin, China

Exploring the relationship between competition and cooperation in water resource exploitation by applying a game model is crucial for achieving stable equilibrium in the presence of environmental externalities. To explore this, we used the Poyang Lake Basin, which is divided into three overly exploited sub-regions, as an example. This paper selected the different types of sub-regions of Poyang Lake Basin as the research subjects, and then proposed a game model to study evolutionarily stable equilibrium strategies. The results are as follows: (1) the behavior of the sub-regions of Poyang Lake Basin are affected by one another and cannot achieve equilibrium through independent games, which also need external forces to coordinate the three reaches; (2) the benefits improve gradually from the state of "non-cooperation" to "full cooperation" and reach an ideal equilibrium when all the sub-regions choose the strategy of cooperation; (3) the strategic choice of sub-reaches is difficult to maximize the overall benefits of the basin in the absence of external constraints. To ensure that the sub-regions choose the cooperative strategy, the central government should support the cooperative subsidies of local governments. In addition to improving the equilibrium state of the sub-reaches, this study proposes the following policy implications: constructing a basin plan and promoting fiscal transfer payments, inducing an industrial gradient transfer, and strengthening the payment for the use of water resources.