4种湿地植物对污水中氮磷的去除效能及其迁移规律

为探讨湿地植物对水体中氮、磷营养元素的去除效果，本试验选取了4种水生植物芦苇、香蒲、菖蒲和水葱作为试验材料，通过分别设置3个不同浓度梯度总氮、总磷的生活污水处理，分析不同植物对污水中总氮、总磷的吸收效果。结果表明:1）不同湿地模拟系统中，植物对总氮的吸收作用以植株地上部分为主。植物对污水中的总氮的累积量大小顺序依次为水葱、芦苇、香蒲、菖蒲。2）不同湿地模拟系统中，植物对总磷的吸收作用虽以根系为主，但受生物量的影响，各植株TP含量仍以地上部分居多。植物对总磷的累积量大小顺序依次为香蒲、菖蒲、芦苇、水葱。3）随着总氮、总磷的处理浓度的增高，污水中总氮、总磷的去除率随之增高，说明植物对氮、磷含量高的污水去除效果较好。4种湿地植物对生活污水中总氮的去除率范围为80.3%~93.6%，对总磷的去除率范围为75.7%~97.2%。

Migration Regularity and Removal Efficiency of Nitrogen and Phosphorus by Four Different Wetland Plants

In order to investigate the capability of wetland plants to absorb nutrient elements of nitrogen and phosphorus in water bodies,four kinds of aquatic plants,Phragmites communis,Typha orientalis,Acorus calamus,Scirpus validus were selected as experimental materials.Three different concentrations of total nitrogen (TN) total phosphorus(TP) were set up to simulate domestic wastewater.Capacities of different plants tested to absorb nitrogen and phosphorus from the simulated wastewater were examined.The main conclusions were as follows:1) in different wetland simulation systems,the cumulative effect of plants on TN was dominated by the aerial part of the plant.The order of the accumulated amount of TN in sewage by plants was S.validus>P.communis>T.orientalis>A.calamus.2) In different wetland simulation systems,the absorption of TP by plants mainly occurred in roots,but due to the influence of biomass,the TP content of plants was still higher in aerial part.The order of the cumulative amount of TP on plants was in the order of T.orientalis>A.calamus>P.communis>S.validus.3) As TN and TP increased in simulated wastewater,the removal rate to TN and TP increased accordingly,indicating that the treatment of high concentration of sewage was beneficial to the removal of TN and TP in the sewage.The removal rates to TN in domestic sewage by the four kinds of wetland plants ranged from 80.3% to 93.6%,and the removal rates to TP ranged from 75.7% to 97.2%.