A tripartite evolutionary game analysis on quality and safety supervision policy in aquaculture supply chain

The quality and safety of aquatic products have become key issues that the government actively addresses. Although Physical Internet offers a novel approach to solving these problems, it still requires an integration with stakeholders’ strategic choices. This paper constructs a tripartite evolutionary model involving three stakeholders: farmers, retailers, and the government. By employing the Lyapunov discriminant method, this study analyzes the stability of equilibrium points within the game system. The results indicate that effectively reducing the income derived from both regulated farming by farmers and drug-free practices by retailers serves as an effective method to prevent unregulated farming and drug use in retail. Moreover, the decision of farmers and retailers to engage in non-compliant behaviour depends on the difference between the income gained from non-compliance and the income from opportunistic behaviour. Additionally, increasing government subsidies for farmers significantly influences their strategic choices, motivating them to adopt standardised aquaculture practices.