| With the continuous economic development and the strong intervention of human activities in recent years, the problem of eutrophication grow more harsh, and it becames one of the important problems which Chinese lakes mast face. The pollution in Yunnan lake is a pressing issue. According to domestic and international management experience, lake has its own characteristics,it is different from water bodies and rivers, the management of lake eutrophication should be followed with the line which combine the sources of pollution conformity with ecological restoration. Rural sewage pollution is increasingly becoming one of important factors on water deterioration. So it is an effective means that try to find out a low-power, less investment, simple technology, easy management and effect treatment of a guaranteed green processing technology.Constructed wetland complies with these requirements and became a newly ecological technology which is the energy saving, low-cost, nitrogen and phosphorus effective removal engineering. This paper relies on the natural state technology fund "The interaction mechanism study on the water flow, sediments, pollutants and plants of the wetland of Altiplano lake " (Project No:50769001), according to the unique conditions of climate resources and the characteristics of plants growth, this paper will research respectively on the types of constructed wetlands, plant species,and plant growth stage, so as to provide a reference for the design and improvement in Yunnan altiplano constucted wetland. The results of the experiment as follows:(1)Selected these plants as the the experiment plants in Constructed wetland:Canna generalis Bailey,Scirpus validus,Eichhornia crassipes,Oenanthe stolonifera,Acorus calamus,Phragmites communis Trim.They grow very well,show that these plants have a strong stain resistance can be applied on Yunnan altiplano artificial wetlands.(2) According to the research on Surface Flow Wetland and Sub-surface Flow Wetland,both find that:during May to July,the removal of Total phosphorus (TP)and Total nitrogen(TN) increases gradually with the plant growth;during August to October,the quality of the experimental water is more satisfactory;during November to December, as the temperature decreases,the removal of TP and TN became decrease, but in the Yunnan Altiplano,the drop is not too great. This shows that Yunnan Altiplano Constructed wetland is feasible to treat the rural sewage pollution,and can get excellent results in TP and TN.This research results play a practical significance role on the use of Yunnan Altiplano Constructed wetland to purify wastewater in rural areas in Yunnan and it becomes a good example.(3)From the comparison treatment effect between the blank field and the plant wetland,it is known that:treatment effect of a plant wetland is significantly better than non-plant systems (blank field), indicating that plants and microbes in the wetland system can not be ignored,and they are important components in wetlands.(4)According to research the results of different plants system in the same period,we can get the following conclusions:In Surface Flow Wetland which plant Eichhornia crassipes and Scirpus validus have advantages in the removal of TP and TN. In Sub-surface Flow Wetland which plant Acorus calamus and Scirpus validus have advantages in the removal of TP,and which plant Eichhornia crassipes,Phragmites communis Trim and Scirpus validus have advantages in the removal of TN.(5) Studies on the removal rate in different types of constructed wetland have shown that Surface Flow Wetland is better than Sub-surface Flow Wetland,but it has the same effet of TP in the wetland that plant Eichhornia crassipes.(6) Yunnan Altiplano Constructed wetland has its own unique treatment characteristics:the removal rate of TP and TN in experimental field is higher than similar systems in other regions in China, especially in winter it is higher than the wetland in northern cold regions.It is shown that Yunnan Altiplano Constructed wetland application is successful, its advantage is very significant, which is closely related to the climatic characteristics in Yunnan Province.So it is worth to promote and bring into play this technology in Yunnan area.
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