Method Of Constructing Distributed Hydrological Model Based On Spatial Information Technology

Along with the changes of global environment and the impact of human activities, hydrological processes are becoming more complex. Traditional lumped hydrological models are now faced with many new challenges. Distributed hydrological models cooperated with geographic information system (GIS), remote sensing (RS) could consider the spatial heterogeneity of concerned catchments and are becoming more popular and necessary for hydrological researches.In this dissertation, on the basis of reviewing and analyzing the advantages and disadvantages of lumped hydrological model and distributed hydrological model at home and abroad, and according to the integration of GIS and RS technology in the application of distributed hydrological model and prospects, with spatial information technology represented by GIS and RS, this paper researches the application method of constructing distributed hydrological model. The design route is that: first, discrete the whole research area into small units and extract the river network based on Digital Elevation Model (DEM) data; second, use traditional lumped hydrological model on each small unit for runoff simulation, taking remote sensing technology as an effective means for getting model parameters and using GIS technology to manage and analysis the input-output data for the calculation of model; finally, the flow data of each unit transfer to the entire valley export through the digital network of basin. The distributed hydrological modeling system could realize: drainage digital networks extraction based on the valley DEM, parametric modeling data collation and analysis, the calculation of hydrological model and the runoff demonstration of simulation results. On the platform of GIS, users only need to operate in accordance with the interface of development, and can realize the rainfall-runoff simulation of hydrologic system effectively and quickly.Selecting the upstream of QingJiang River basin as study area, and constructing distributed hydrological model based on Xin'anjiang model to do rainfall-runoff simulation, this test shows that, at the support of GIS and RS, the designed system can realize the segmentation of whole drainage, parameters of acquisition and management and runoff calculation.