水培植物对城市污染河道水体净化的效果

选取两种景观植物——绿萝和千屈菜，利用典型城市黑臭河道温州市横渎河河水水插生根并培育成熟，并对横渎河河水以及与横渎河相交汇的山下河的河水进行净化试验。同时与经土培生根的两种植物进行对照，比较水质净化效果。结果显示采取两种生根方式培育的植物对横渎河河水的净化效果差异不显著。而对于山下河河水，水插生根植物净化效果优于土培生根植物。其中水插生根绿萝对山下河河水的COD、NH；-N、TN和11P的去除率比土培生根绿萝高出11．9％、4．8％、12．6％和6．2％，水插生根千屈菜对山下河河水的COD、NH4-N、TN和TP的去除率比土培生根千屈菜高出13．0％、13．3％、8．1％和5．5％。试验表明水插生根培育的植物对污染水体净化效果良好，可作为城市河道生态修复技术中一种实用的植物培育栽种方式进行推广应用。

Water Purification Effect of Hydroponic Plants for Urban Polluted Rivers

Two typical aquatic landscape plants, named Scindapsus aureus and Lythrum salicaria, were cultivated by Hengdu River directly, which was a typical urban malodorous river in Wenzhou. Compared with purification effects of soil-rooting plants, purification effects of two kinds of water-rooting plants on the polluted water from Hengdu River and Shanxia River were investigated in those tests. The results show that the two kinds of rooting patterns have a similar treatment effect on polluted water from Hengdu River. For polluted water from Shanxia River, water-rooting plants have better effects on purification than soil-rooting plants. The removal rates of COD, NH4- N, TN and TP by water-rooting Scindapsus aureus are 11.9 %, 4.8 %, 12.6 % and 6.2 % higher than that by soil-rooting Scindapsus aureus in polluted water from Shanxia River. The removal rates of COD, NH4- N, TN and TP by water-rooting Lythrum salicaria are 13.0 %, 13.3 % , 8.1% and 5.5 % higher than that by soil-rooting Lythrum salicaria, respectively. The tests show that the plants cultivated by contaminated river water have a beneficial purification effect on polluted water. Based on the preferable effect of pollutants removal and good practicality, this method of plant cultivation is recommended for the phytoremediation of urban rivers.