Assessment of carrying capacity and management practices for Litopenaeus vannamei industrialized aquaculture based on an ecosystem model

Abstract

Highlights: • An ecosystem model was developed for the indoor industrialized aquaculture system. • Model captured shrimp growth and nutrient dynamics (nitrogen, phosphorus). • The system's carrying capacity was assessed based on the discharge standard. • Evaluated feed quality, water exchange and tailwater treatment effects on system. • Tailwater treatment maximized carrying capacity and minimized nutrient discharges. Abstract: The sustainability of indoor industrialized aquaculture is challenged by resource limitations and environmental constraints. Thus, an integrated ecosystem-level assessment is essential to conserve water resources, improve production efficiency, and enhance the sustainability of the system. In this study, an ecosystem model for a Litopenaeus vannamei industrialized aquaculture system was developed to simulate shrimp growth, and its effects on nitrogen and phosphorus dynamics were examined. This study assessed the carrying capacity of the system, overall benefits, and the effects of management practices by integrating model simulations with discharge standards for nitrogen and phosphorus in tailwater. The results revealed a carrying capacity of 409 ind·m−2 for juvenile shrimp (body length: 4.24 ± 0.37 cm). Compared with the current stocking density (880 ind·m−2), the yield and economic benefit decreased by 53.5 % and 71.5 %, respectively. A simulation of management practices indicated that the carrying capacity could be increased to 449 ind·m−2, 593 ind·m−2, and 1193 ind·m−2 by enhancing feed quality, increasing the water exchange rate, and adopting tailwater treatment technology, respectively. Notably, adopting tailwater treatment technology would increase current stocking density to 1193 ind·m−2 and produce an increase of 33.5 % in economic benefit, a reduction of 26.2 % in tailwater discharge per unit yield, and 48.2 % and 49.0 % reductions in the discharge of total nitrogen and total phosphorus in tailwater, demonstrating water conservation and pollution control. This study provides a theoretical foundation and practical references for the standard discharge of tailwater and efficient resource utilization in L. vannamei industrialized aquaculture systems