Abstract:Ecological water demand for wetland is a newly integrated concept, which are required for maintaining ecosystem structure and function, protecting biodiversity, sustaining human life and activities, and improving environment quality. In arid and semi-arid areas of northern China, lakes have been facing a number of problems such as dried-up, shrinkage and serious water pollution. The estimation of ecological water demand for lake is the basic precondition to keep rational utilization or restoration of lake e...