The Study Of Discharged Eco-Environmental Flow For YiHe LiZhuang Gate In ShanDong Province

With the rapid development of our social-economic, human had been controling of water resources through a large number of water conservancy regulation, which made the habitat fragmentation phenomenon.Recognized the impact of human activities on river ecosystems,China began to take the appropriate river recovery behavior. Attendant problems is how to calculate the eco-environmental flow with the purpose to meet the river’s ecological functions.This Paper analysised the concept, meaning, calculation method and significance of Dams eco-environmental flow based on progress of the research,and chose the Tennant method improved after in contrast to a variety of eco-environmental flow methods.This paper also analysised the state of ecological and environment of Yihe Li Zhuang gate inShandong province,calculated the eco-environmental flow by using the improved Tennant method, and verified its legitimacy and operability with the evaluation and analysis by methods and results.The paper was not only important to maintain the river eco-environmental safety and security Yihe Li Zhuang gate downstream,but also provide a reference for the determination of eco-environment flow for similar rivers,in order to achieve a reasonable use of water resources and promote the sustainable development of the basin.Through the research above,the conclusions was as following:①Ecological environmental flows in dualistic water cycle had the property of "nature-society",including the"ecological and environmental" two parts of the connotation of flow, with the features of Threshold value, spatial and temporal characteristics and quality consistency.②This paper improved the Tennnant method after in contrast to a variety of eco-environmental flow methods in the concepts of seasonal hydrology and sediment transport improvements.Then determined the eco-environmental flow of LiZhuang Gate discharged.③Verificated the improved Tennant method by the ecological hydraulic radius method and ten driest months flow method.The results showed that the result of the improved method can meet the eco-environment goals incluing river’s sediment transport,ecological breeding of fish and river water quality dilution purification.④Evaluated the calculation results of the eco-environmental flow by the binary evaluation of water quantity and quality method.The results showed that:the eco-environmental flow can meet the ecosystems and purification goals of Li Zhuang gate downstream whether in quantity or quality.