Improving Fishpond Sediment by Aquatic Vegetable Rotation

Ling Tao；Chun-Xue Zhang；Jian-Qiang Zhu；Shi-Yang Zhang；Xiao-Li Li；Gu Li

Heavy metal ； phosphorous form ； pond aquaculture ； sediment

Advance Journal of Food Science and Technology

4卷5期（2012 / 10 / 20）

327 - 331

英文

Continuously intensive fish farming results in pond degradation that needs to be improved. Therefore, the experiment rotating intensive fish culture with two aquatic vegetables lotus (Nelumbo nucifera) and water chestnuts (Eleocharis dulcis) cultivation is conducted aiming at determining the effect of rotation as a sediment management technique on improving the pond sediment and assessing the food safety risk of the vegetables cultivated in the pond sediment from the aspects of heavy metal. The results showed that after rotation, the content of Total Nitrogen (TN) and Organic Matter (OM) in the upper 10 cm sediment decreased significantly (p＜0.05), with TN content reduced 1.05 and 0.74 g/kg; OM content reduced 0.59 and 0.37%, respectively. The contents of Organic-Phosphorus (OP) and Fe/Al-bound Phosphorus (Fe/Al-P) in the sediment decreased significantly (p＜0.05), with OP reduced 0.05 and 0.04 g/kg, Fe/Al-P reduced 0.19 and 0.15 g/kg, respectively. The heavy metal contents of As, Pb, Cd, Hg, Cr and Zn except Cu in the pond sediment were under Chinese National II Soil Criterion and the contents of As, Pb, Cd, Hg, Cr, Cu and Zn in edible vegetable rhizomes satisfied Safety Requirements for Non-environmental Pollution Vegetable. Rotation of fish culture with aquatic vegetables cultivation effectively mitigated excessive nutrient load in the sediment while recycled the nutrient in the sediment to produce safe vegetables. It could be considered as a viable sediment quality improving technique.