不同水蕹菜覆盖率去除松浦镜鲤池水中氮磷的效果

Removal of Nitrogen and Phosphorus From Water in Songpu Mirror Carp Ponds by Water Spinach Under Different Coverage Rates

2017年7月1日—9月13日,在水深1.5 m、面积667 m2主养松浦镜鲤Cyprinus carpio Songpu、套养长丰鲢Hypophthalmichthys molitrix的精养池塘中,设长250 cm、宽100 cm的生态浮床,水蕹菜Ipomoea aquatica的覆盖率分别为15%、20%、25%和30%,探讨不同覆盖率下水蕹菜对精养鱼池氮、磷吸收的效果。75d的养殖和氮磷含量监测结果表明,试验池塘与对照池塘(覆盖率0%)间水中氮磷含量差异显著(P<0.05);四种覆盖率浮床对水体总氮的去除率分别为45.02%、53.47%、59.17%和69.84%,对总磷的去除率分别为48.48%、55.93%、64.91%和76.67%,水体氮磷去除率与覆盖率呈正相关。生态浮床覆盖率在20%~30%时,氮磷去除效果较好,考虑生产成本,水蕹菜覆盖率以25%为宜。该研究结果可为池塘水体富营养化生态防控的推广应用提供理论依据。

The effects of water spinach Ipomoea aquatica on absorption of nitrogen and phosphorus were investigated in water of a 1.5 m deep and 667 m2 intensive polyculture ponds of mirror carp Cyprinus carpio Songpu with Changfeng silver carp Hypophthalmichthys molitrix under different coverage rates of 15%,20%,25%and 30%by water spinach in an ecological floating bed of 250 cm long and 100 cm wide from July 1 to September 13,2017 for 75 days to evaluate the removal of nitrogen and phosphorus from water in Songpu mirror carp ponds by water hyacinth.The results showed that there was significant difference in nitrogen and phosphorus content between the test ponds and the control pond(0%of coverage)(P<0.05),with the total nitrogen removal rate of 45.02%at the coverage floating rate of 15%,53.47%at the coverage floating rate of 20%,59.17%at the coverage floating rate of 25%and 69.84%at the coverage floating rate of 30%,and with total phosphorus removal rate of 48.48%at the coverage floating rate of 15%,55.93%at the coverage floating rate of 20%,64.91%at the coverage floating rate of 25%and 76.67%at the coverage floating rate of 30%,indicating that coverage rate was positively correlated with coverage floating rate.The better removal efficiency of nitrogen and phosphorus was observed at the coverage rate of 20%~30%in an ecological floating,considering the production cost,the optimal coverage rate of water spinach being 25%.The findings can provide a theoretical basis for the popularization and application of eutrophication ecological prevention and control in ponds.