Bioremediation of sediment typed eutrophic river with adjustable submerged vegetation net-beds technology
KANG Yin-hua, HE Pei-min*, LI Juan-ying, WU Hai-long, WEN Wen-ke, SHAO Liu, ZHANG Yin-jiang
1. College of Fisheries and Life Sciences, Shanghai Ocean University, Shanghai 201306, China; 2. Shanghai Research Center of Universities for Water Environment & Ecology Engineering, Shanghai Ocean University, Shanghai 201306, China
The flowing sediment typed river water in the Lingang New City, Shanghai was restored with the continuous adjustable Alternanthera philoxeroides and Myriophyllum verticillatum submerged vegetation net beds. The bioremediation efficiency was evaluated by 4-month continuous monitoring of total nitrogen(TN), nitrite nitrogen(NO2-N), nitrate nitrogen(NO3-N), total phosphorus(TP), phosphate(PO4-P) and Secchi depth(SD) from June to December in 2011. The results showed that the transparency and water quality of the eutrophic sediment typed river were improved significantly. The TN, NO2-N, NO3-N, TP, PO4-P concentrations of the eutrophicate water were decreased by 69.58%, 67.91%, 84.48%, 62.26%, 82.61% and 45.48%, 58.32%, 76.56%, 43.12%, 73.68%, respectively with Alternanthera philoxeroides and Myriophyllum verticillatum submerged vegetation net beds. The transparency of sediment typed river water was increased by 18% and 26%, respectively with Alternanthera philoxeroides and Myriophyllum verticillatum submerged vegetation net beds. It indicated that Alternanthera philoxeroides submerged vegetation net bed was better than Myriophyllum verticillatum submerged vegetation net bed in reducing nutrient. While Myriophyllum verticillatum submerged vegetation net bed was better than Alternanthera philoxeroides submerged vegetation net bed in increasing transparency of the sediment typed river water. So combining both Myriophyllum verticillatum and Alternanthera philoxeroides submerged vegetation net beds would increase bioremediation efficiency for removing nutrients and sediment in rivers.