水生植物浮床对城市污染水体的净化效果研究

Study on the purification effects of aquatic plant floating-beds for urban polluted water

以香菇草(Hydrocotyle vulgaris)、睡莲(Nymphaea tetragona)和西伯利亚鸢尾(Irissibirica)3种水生植物为试材,制成植物浮床,研究3种植物以及无植物浮床对城市污染水体中污染物的净化效果,试验共持续35 d.结果表明:3种植物在污染水体中能保持较强生命力,试验结束时,其株高、根长及生物量均有显著增加,增长率表现为睡莲>香菇草>西伯利亚鸢尾;3种植物对水体中CODCr、NH4+-N、TN和TP均有明显去除效果,香菇草、睡莲、西伯利亚鸢尾对水体中的TN去除率分别为90.0%、85.7%和81.2%,对TP的去除率分别为68.6%、57.0%和62.8%;3种植物浮床去除率显著大于对照浮床(P<0.05).试验表明,3种植物对污染水体均有很好的净化效果和一定的景观价值,可作为城市景观污染水体治理的优良物种而推广使用.

Three kinds of ecological floating-beds were made of Hydrocotyle vulgaris,Nymphaea tetragona and Iris sibirica,respectively,to study their purification effects on removing pollutants of urban polluted water.The experiment lasted for 35 days.The results indicated that the three aquatic plants were adaptable to grow in the urban polluted water,and their biomass,height and root increased significantly at the end of the experiment.The growth rates were Nymphaea tetragonaHydrocotyle vulgarisIris sibirica.Three plants had strong ability to remove CODCr,NH＋4-N,TN and TP,which were higher than that in the control treatments（P0.05）.The removal rates of TN by Hydrocotyle vulgaris,Nymphaea tetragona and Myriophyllum verticillatum were 90.0%,85.7% and 81.2%,respectively.In addition,the removal rates of TP by Hydrocotyle vulgaris,Nymphaea tetragona and Myriophyllum verticillatum were 68.6%,57.0% and 62.8%,respectively.Based on their significant effects on nitrogen and phosphorus removal,the three plants are recommended as species of aquatic plants in ecological restoration engineering of urban polluted water.