Shifosi Reservoir Water Environment Problem Analysis And Comprehensive Control Measures Layout Research

Shifosi Reservoir,also known as Shifosi artificial wetland.Shifosi constructed wetland was built on the basis of Shifosi reservoir.It is a typical large-scale surface flow constructed wetland in Northeast China.Since its establishment,it has improved the regional environment and purified the water quality.But with the passage of time,there are some new water environmental problems.In this paper,the water environment problems are analyzed through water quality monitoring,field survey,test and model analysis and evaluation,and the comprehensive treatment measures are put forward in view of the problems.The main research contents are as follows:?1?The comprehensive water quality identification index method was used to analyze and evaluate the water quality of the 2009-2015 year's import and export areas of the Shifosi reservoir.The selected evaluation indexes were seven water quality monitoring pollution indexes,such as DO,BOD₅ and COD_MN,and the evaluation period was in flood season and non flood season.The results show that the export of wetland is basically maintained in class III water quality standard,and the effect of wetland on water quality is good in general.But when evaluating the index of single pollution,the two main pollution index factors of wetland water quality are TN and TP.From the change of the comprehensive water quality identification index,the wetland has a clean water quality.The problem of becoming saturated.?2?The use of seasonal Kendall test on Shifosi Reservoir,the changing trend of the seven pollution indexes of water quality for export,The results show that the water quality of the wetland exportation section is obviously better than that of the imported section.It shows that the wetland plays an excellent role in the function of the interception and purification of the pollutants,but the CODcr and TN at the inlet of the wetland show a rising trend,which indicates that the two pollutants in the upstream water are not well controlled.It is also the main part of the current reservoir.Water environment problem?3?Investigation and analysis of sediment in three typical areas of Shifosi reservoir.The results show that there is a serious problem of silting in the wetland,which is the most serious deposition in the main river basin,because the area of the area is large,the sediment in the upper reaches of the river is retained in the bottom of the river and the sediment is not dredged for a long time.Secondly,the main reasons for the siltation are the death of aquatic animals and plants.The sediments deposited at the bottom of the water body are accumulated for a long time.The sediments at the bottom will release nitrogen,phosphorus and other nutrients due to the influence of the concentration changes.?4?Through field investigation and analysis,it is found that there are other water environmental problems,including the construction of aquatic plants,the phenomenon of biological siltation,the overgrowth of submerged plants and floe plants,the comprehensive planning and management of wetland and so on.?5?According to the target and principle of functional location and water environment protection,the Shifosi reservoir is divided into four functional areas:water conservation area?divided into herbage planting unit and water conservation unit?,wetland ecological landscape area?divided into reed cattail area,lotus area and artificial island area?,reservoir vegetation filter zone and main river area;Each district plays a different role in water environment protection.Through the selection and applicability analysis,the following techniques were selected to be applied to this study:aquatic plant purification technology,ecological floating bed technology,sediment dredging technology,bank bank vegetation filter zone technology,aquatic plant management technology and prohibition control technology.?6?According to the characteristics of each area,the selected technical measures are applied to various functional areas according to the characteristics of each area.The water environment problems existing in the reservoir of the Shifosi reservoir are comprehensively treated by the combination of the three forms of engineering measures,plant measures and aquatic plant management measures.We should strengthen the resource construction of aquatic plants and reduce the two pollution.Constructive suggestions are put forward for pollution control in the upper reaches of reservoirs.Through the layout of comprehensive control measures,all kinds of water environmental problems can be solved,and the water environment can be protected.