贯泾港构筑根孔湿地水质净化效果

Water purification efficiency of Guanjinggang constructed root channel wetland

贯泾港构筑根孔湿地是石臼漾湿地的升级版,采用前塘-植物床/沟壕湿地-后塘复合系统净化平原河网污染水源,旨在为贯泾港水厂供水。研究了调试运行期湿地对污染水源的净化效果。结果表明,湿地对水源主要指标的去除率为:TSS(22.45%),NH+4-N(66.80%),TN(45.44%),SRP(66.67%),TP(50.28%),TOC(29.39%),COD(59.26%),chl-a(68.93%),chl-b(91.82%),chl-c(84.15%),藻类密度(42.42%),Cr(31.74%),Cu(23.21%),Ni(82.47%),Zn(52.24%),Pb(40.44%),离子总量(10.71%)。比较得知,水厂现状水源南郊河与湿地水源海盐塘的水质互有优劣,但前者多数指标劣于湿地出水水质。可以预期,随着贯泾港湿地生态系统逐渐成熟,将为水厂提供稳定而良好的净化原水。提出了贯泾港湿地在调试运行期存在的问题和建议。

Guanjinggang constructed root channel wetland is an updated version of Shijiuyang wetland.It adopts complexes of pre-pond,plant-bed/ditch wetland and post-pond to purify the polluted water source in plain stream network and aims to provide purified raw water for Guanjinggang drinking water plant.Purification efficiency of Guanjinggang wetland on polluted water source was examined during its commissioning period.Removal rates of wetland on major indexes were as follows： total suspended solids（22.45%）,NH＋4-N（66.80%）,TN（45.44%）,soluble reactive phosphorus（66.67%）,TP（50.28%）,TOC（29.39%）,COD（59.26%）,chlorophyll-a（68.93%）,chlorophyll-b（91.82%）,chlorophyll-c（84.15%）,algae density（42.42%）,Cr（31.74%）,Cu（23.21%）,Ni（82.47%）,Zn（52.24%）,Pb（40.44%）,and total ionic content（10.71%）.By comparison,Nanjiaohe stream as present water source of drinking water plant and Haiyantang stream as water source of wetland have pros and cons to each other.However,most water quality indexes in Nanjiaohe stream were inferior to those in wetland effluent.Expectedly,with the development and maturation of Guanjinggang wetland ecosystem,it will provide stable and significantly improved raw water for drinking water plant.Existing problems and suggestions of Guanjinggang wetland during its commissioning period were put forward.