Study On Ecological Water Demand Process Of Guan River Based On Ecological Protection Objectives

Providing reasonable ecological flow for rivers is an important means to maintain the health of river ecosystem.The ecological protection objectives of different ecosystems are different,and the water demand of ecological environment is also different.The determination of ecological protection objectives is of great significance to the determination of ecological water demand.Taking Guan River as the research object,this paper studies and determines the quantitative method of ecological water demand suitable for Guan River Based on different protection objectives of river ecosystem.The main research contents are as follows:(1)The goal and composition of ecological water demand of Guan River were determined.Based on the analysis of the ecological flow,water quality,biological habitat and landscape of Guan River,the current ecological environment problems of Guan River were identified.On this basis,according to the functional characteristics of Guan River ecosystem,the protection objectives of ecological water demand of Guan River were determined,and the components of ecological water demand of Guan River were identified,including minimum ecological water demand,self purification water demand,landscape water demand and sensitive water demand There are five parts: ecological water demand and high flow pulse.(2)The calculation method system of ecological water demand of Guan River was constructed.Based on the analysis and summary of the characteristics and applicability of river ecological water demand calculation methods at home and abroad,this paper selects the calculation methods suitable for different ecological water demand components of Guan River,including Tennant method,water quality model method,water balance method,habitat simulation method and IHA method,and constructs a set of calculation method system of ecological water demand of Guan River considering hydrological process,water quality and biological habitat conditions.(3)The ecological water demand process of Guan River was determined.By using the proposed method system of ecological water demand calculation,the ecological water demand of Guan River under different ecological protection objectives is obtained,and the process of ecological water demand of Guan River is defined;the calculation results are compared with the average flow method and flow duration curve method in the driest month,and the rationality of the calculation results is analyzed;By calculating the guarantee rate of ecological water demand in water quantity and time,the satisfaction degree of ecological water demand of Guan River was evaluated.