In situ nutrient removal from aquaculture wastewater by aquatic vegetable Ipomoea aquatica on floating beds.
Nutrient-rich effluents caused rising concern due to eutrophication of aquatic environment by utilization of a large amount of formula feed. Nutrient removal and water quality were investigated by planting aquatic vegetable on artificial beds in 36-m(2) concrete fishponds. After treatment of 120 days, 30.6% of total nitrogen (TN) and 18.2% of total phosphorus (TP) were removed from the total input nutrients by 6-m(2) aquatic vegetable Ipomoea aquatica. The concentrations of TN, TP, chemical oxygen demand (COD) and chlorophyll a in planted ponds were significantly lower than those in non-planted ponds (P<0.05). Transparency of water in planted ponds was much higher than that of control ponds. No significant differences in the concentration of total ammonia nitrogen (TAN), nitrate nitrogen (NO(3) (-)-N) and nitrite nitrogen (NO(2) (-)-N) were found between planted and non-planted ponds. These results suggested that planting aquatic vegetable with one-sixth covered area of the fishponds could efficiently remove nutrient and improve water quality.
Li
Wenxiang
W
State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, Hubei Province, China. liwx@ihb.ac.cn
Li
Zhongjie
Z
D000821:Animal Feed; D000818:Animals; D002347:Carps; D005399:Fishes; D005502:Food; D005504:Food Analysis; D019015:Geologic Sediments / Q000032:analysis; D027741:Ipomoea / Q000254:growth & development*; D012621:Seasons; D014675:Vegetables; D014865:Waste Disposal, Fluid / Q000379:methods*