Research On Compute Pattern Of Ecological Water Demand In Rivers And Its Application

The control of ecological water utility is based on researches of ecological water demand in rivers, while controlling problems on ecological water utility should have their criterions. for rivers the controlling criterions are the characteristics of ecological water demand, the main researches come down to regulation of ecological water demand in rivers, they are researched step by step in rivers in north of china, from the view of quantities in run offs and different objects of ecology demand in rivers, the following contents are researched gradually on minimum ecology flow and fitting ecology flow.Firstly, researches about ecological water demand in rivers are summarized, different viewpoints and calculation approaches are classified, and the characteristics and applicability of the approaches are commented.Secondly, the ecological effects produced in water cycles are analyzed, types of water ecosystem are compartmentalized in condition of rainfall and runoffs, the researching contents and expression forms and the hierarchy of water demand in rivers are analyzed also, the minimum and fitting ecology flows are defined from the viewpoints of survival requirements and integrity and stability of hygrophilous biology in rivers in the north of china, and the ecological functions and water levels conforming approaches in groundwater are analyzed.Thirdly, through analyses on the critical theories of physiognomy in drainage basins the factors of hydrology and conformation in rivers are connected in the aspect of minimum ecology flow, the indices of river survival and inferior changes out of happening is conformed by the relations of hydraulic geometry forms and conditions of runoff in river system, forms of different river transects and applicable conditions are classified and simulated, the rules and processes are given in the conforming on minimum ecology flow.Fourthly, the fitting ecology flows are researched gradually, in one aspect, fish was selected in necessary condition of integrity as the key indicated species in river ecosystem, by the flow velocity of spawning and survival in multiplying on fish demand, the fitting ecology flows are estimated, in another aspect, based on the MSY object of fishery managements the surplus production model was analyzed, and stochastic differential model was established, the fitting ecology flows are estimated by the relations of fishery yield and runoffs, those for offering the reference evidences to similar researches in areas of biology data lacking.Lastly, depended on the computation of anterior levels of ecology flow in liaohe rivers the controlling criterions of ecological water utilities and analysis methods are afforded, and recent status of ecological water utilities in west of liaohe are evaluated, and the characteristics of those multi ecology flows are analyzed also, the ecology flows of experience models on subarea are formed primarily by that in liaohe rivers.