TREATMENT OF WASTEWATER FROM INTENSIVE STRIPED CATFISH FARMING USING HYMEN A CHNE A CUTIGL UMA IN BATCH SURFACE-CONSTRUCTED WETLAND

摘要

Intensive striped catfish (Pangasianodon hypophthalmus) farming has recently expanded owing to its economic benefits but it has led to severe aquatic pollution. In this study, a batch surface-constructed wetland system cultivated with Hymenachne acutigluma grass was designed to treat wastewater collected from catfish ponds. The planted wetland system showed effective operation, as 81.7% of NO3--N, 63.6% of NH4+-N, and 77.5% of PO43--P (w/w) in the wastewater were removed over four months. Besides, the wetland significantly decreased the chemical oxygen demand and total suspended solids from the wastewater. The absorption by the grass resulted in the removal of 20.3 and 22.2% of the total nitrogen (N) and phosphorus (P) from wastewater, respectively. The determination of the nutrient mass balance in the planted system showed that phosphorus in the wastewater was mainly removed through sediment deposition, while a large amount of nitrogen was not lost because of the sediment deposition and plant uptake. Moreover, H. acutigluma cultured in the system can serve as food for cattle. This study shows an ecofriendly approach for the effective remediation of wastewater obtained from the farming of intensive striped catfish.