In Situ Purification Experiment of a Mangrove–aquaculture Coupling System: A Case Study of a Crab Pond in Wanning, Hainan Province

AbstractAquaculture development and expansion can destroy and reduce tropical mangrove systems, while discharging sewage into the ocean. This study introduced a new mangrove system into an aquaculture pond to establish a mangrove–aquaculture coupling system. This study aims to reduce pond water eutrophication and decrease nutrient discharge into the ocean without affecting aquaculture. Results show that mangrove planting does not affect Scylla serrata growth (mud crabs), but does stabilize pond environments. While mangrove‐planting inhibits nitrogen and reactive P (PO43−) accumulation in ponds, it is a poor inhibitor of total phosphorus accumulation. The average nitrite (NO2−), reactive P (PO43−), and total nitrogen (TN) contents decreased by 80.46, 35.47, and 31.01%, respectively. This mangrove–aquaculture coupling system provides a method to balance economic development needs with the ecological needs of mangrove wetlands. This study offers suggestions for establishing this system and its associated waste aquaculture pond transformation.