调蓄经济植物湿地技术在农田径流污染控制中的工程应用及评价

为评价调蓄经济植物湿地技术在农田径流污染控制中的运行效果和经济效益，采用现场调研长期跟踪监测调蓄经济植物湿地进、出水水质和水量变化，深入探索其营养盐质量浓度分布特征及其去除效能.结果表明:①调蓄经济植物湿地能够有效截留营养盐，稳定出水水质，2015年7月-2017年4月出水ρ（TN）、ρ（TP）和ρ（COD_Cr）平均值分别为1.2、0.07和17.0 mg/L，TN、TP和COD_Cr去除率分别为65.8%、75.5%和41.3%.②不同调蓄量下TN和TP去除率随着进水水量的增大而减小，表现为枯水期>平水期>丰水期；COD_Cr去除率与调蓄量之间呈负相关，表现为丰水期>平水期>枯水期；在调蓄经济植物湿地中单位面积TN、TP和COD_Cr去除负荷量表现为丰水期>平水期>枯水期.③调蓄经济植物湿地中莲藕、海菜花和螺蛳产量分别为26.25、22.50和2.46 t/（hm2·a），氮、磷去除总量分别为275和30 kg/（hm2·a）.研究显示，调蓄经济植物湿地能够有效截留氮、磷，在不同水文期均有良好的净化效果，不仅具备景观效益，且具有良好的经济价值. 

Application of Storing Economic Constructed Wetland in the Treatment of Contaminated Water from Farmland Runoff

To evaluate the application and economic performance of storing economic constructed wetland in the treatment of contaminated water from farmland runoff, long-term water quality and quantity were regularly investigated and monitored for the analysis of distribution characteristics and removal efficiency of nutrients. The result showed that:(1) The nutrients were effectively intercepted and stable nutrient concentrations in the effluent of the wetland and a good removal efficiency were obtained. The average ρ(TN), ρ(TP) and ρ(COD_Cr) of the effluent was 1.2, 0.07 and 17.0 mg/L from July 2015 to April 2017, respectively. Favorable removal efficiency of TN, TP and COD_Cr with the values of 65.8%, 75.5% and 41.3% were achieved, respectively. (2) The removal efficiency of TN, TP were decreased with increasing influent water quantity under different storage capacities. The removal rate of nitrogen and phosphorus was in the order of dry season > normal water season > wet season, while removal efficiency of COD_Cr was successively in the normal water season, dry season and wet season. However, the removal load per unit area of nutrient TN, TP and COD_Cr followed the order of wet season > normal water season > dry season. (3) The yield of Nelumbonucifera Caertn, Otteliaacuminata var. acuminate and Margarya melanioides was 26.25, 22.5 and 2.46 t/(hm2·a) in the storing economic constructed wetland. Nitrogen and phosphorus mass removal were 275 and 30 kg/(hm2·a), respectively. Nitrogen and phosphorus were effectively removal and good removal efficiencies were achieved in different water season in the storing economic constructed wetland. Thus, storing economic constructed wetland not only has a good landscape, but also has perfect economic value.