Neoclassical economic analysis of water exchange and recirculating aquaculture systems in shrimp farming

The shrimp farming industry, as one of the fastest-growing sectors within marine aquaculture, has played a significant role in improving China's food supply, promoting local economic development, and increasing farmers' incomes. In recent years, the factory farming model for shrimp in China has developed rapidly. To gain a deeper understanding of the various aquaculture technologies, we utilized bioeconomic methods to study the differences and economic efficiencies of different technologies in shrimp factory farming. The results indicate that water quality factors negatively impact shrimp weight, with interactions among them. The water exchange model significantly increases yield, while moderate recirculation intensity also has a positive effect. Economic analysis shows that a one-unit price increase leads to higher revenue: 1.33 units for the water exchange model and 1.16 units for moderate recirculation. The water exchange model yields a net profit of US$ 471.34 per hectare, with each additional weight unit adding 30.3 units to revenue. The recirculating water model generates US$ 124 per hectare, with each weight unit increasing revenue by 26.3 units. This provides relevant information for shrimp farming producers in their management decisions to improve both economic and ecological benefits. • Chemical oxygen demand (COD) had an indirect positive influence on nitrogen compounds of 0.594. • Phosphorus compounds had an indirect negative effect on nitrogen compounds of −0.311. • The water exchange model nets $471.34 per hectare and adds $30.3 for each weight unit. • The recirculating water model nets $124 per hectare and adds $26.3 for each weight unit.