典型华南人工湿地植物的净水效果研究

Study on Water Purification Effect of Different Plants in Constructed Wetland of South China

人工湿地具有运行成本低、投资少,不存在二次污染,有良好的景观效果,建设周期短见效更快的优点。在人工湿地的构建中,植物对湿地净化污水起到极其重要的作用和影响。为了筛选适宜于华南地区气候条件下的湿地植物,研究了植物对低浓度生活污水的适应性,测定了污染物的净化效率及根区基质酶活性和净化效率的关系。试验结果表明,灯芯草、石芒草、蝎尾蕉和花叶良姜明显不适应污水浇灌的模拟人工湿地环境,而梭鱼草、香蒲、菖蒲、象草、薏苡、风车草生长速度快,生物量大,适宜在污水环境中种植。综合供试湿地植物对污水环境的适应性、净化能力、抗逆性和景观效果等指标,象草、菖蒲、香蒲、薏苡、风车草、水芋、春芋、红蛋和梭鱼草是比较适合在人工湿地系统中种植的,磷酸酶活性和脲酶和与盆栽的COD_(Cr)去除率之间存在着显著的关联性,植物根区基质脲酶酶活性与盆栽的TN去除率和TP去除率之间没有显著的关联性。

Constructed wetlands feature low operating costs and investment,no secondary pollution,good landscape effects,and fast results in short construction periods.In the construction of constructed wetlands,plants play an extremely important role in the purification of sewage from wetlands.To screen suitable wetland plants under the climatic conditions in south China,this paper studies the adaptability of plants to low-concentration domestic sewage and determines the purification efficiency of pollutants and the relationship between the activity of root-zone matrix enzymes and purification efficiency.The test results reveal that rushes,river grass,heliconia,and shell ginger are obviously not suitable for the simulated constructed wetland environment irrigated by sewage,while pickerelweed,cattails,calamus,elephant grass,coix,and windmill grass grow fast and have large biomass,which are suitable for planting in sewage environment.Considering indicators such as the adaptability,purification ability,stress resistance,and landscape effect of the tested wetland plants to the sewage environment,it is concluded that the elephant grass,calamus,cattails,coix,windmill grass,calla,philodendrons,Echinodorus Osiris,and pickerelweed are more suitable for the constructed wetland system.There is a significant correlation between the phosphatase activity and urease and the COD_(Cr) removal rate of potted plants,and the enzyme activity of the rootzone matrix urease is not significantly correlated with the TN removal rate and TP removal rate of potted plants.