Study On Ecological Restoration In The Lower Reaches Of Heihe River Basin Based On Rational Water Resources Allocation

In this dissertation, by adopting the method of field investigation combined with office analysis and simulation, GIS technology as the platform of process, analysis and simulation of key data, and modern landscape analysis technology,especially the analysis of the balance of landscape engross and supply, ecology evolvement situation in downstream of Heihe river is analysed; through the analysis of drive mechanism of ecology evolvement, it shows that ecology depravation occuring downstream of Heihe river is the result of synthetical effect of the frail ecology environment background and irrational human activity, especially caused by human's over impropriation of water resources.Operation mechanism of moisture-ecology is also profoundly anatomised in this dissertation. Based on the numerical simulation system of ground water for the plain region in downstream of Heihe river, the model system and GIS, distribution map of bury of ground water and vegetation are superposed, the drive of bury of ground water to the evolution of vegetation community is analysed from the angle of spatial differentiation, and the LOGSTIC fit function embodying the relationship of the coverage of vegetation community of turf forest land open forest land shrub land and bury of groundwater is built; Guided by the theory of oasis "zone and layer structure", the dynamic influence of the distance from water source to the distribution of landscape is profoundly revealed.On the basis of the analysis of ecology evolvement and interaction effect of moisture-ecology, depending on the spatial decision-making of GIS, the ecology protection and restoration object in downstream of Heihe river basin is further establishedo Based on the object of ecological restoration, the concept of Ecological Water Requirement is defined from the angle of science of water resources. In the region in downstream of Heihe river with ecology degradation, Ecological Water Requirement includes not only the part for the restoration of natural vegetation ecology system and rivers and lakes ecology system, but also the part for the restoration of ground water level. The quantities of water for the above three parts are calculated according to different Ecological Water Requirement for different restoration objects in the water distribution influence area in downstream of Heihe river basin.The basic thought of ecological restoration simulation model in downstream of Heihe river basin, which is based on rational distribution of water resource, is putforward. And the ecological restoration model and multiple objective model with rational distribution of water resource and facing all attribute are both built, and its coupling and nesting with ground water numercial simulation and information alternation with ecological restoration model are also realy fulfilled. The application of the ecological restoration simulation model in downstream of Heihe river basin on simulation and forecasting the restoration status of natural oasis under different level serious of water distribution scheme is discussed at last in this paper.