| It is an effective way to realize the highly quantitative study on the geographical process that associates with main geographical factors such as climate, hydrology, topographic features, soil, vegetation and human activities with geographical process by selecting suitable spatial scales and using mathematic models based on computer.Distributed simulation study of multi-gegraphical process was carried out in the study area of Lianshui Basin, Xingguo County, Jiangxi province supported by RS ans GIS, using the model developed ourself. This project is funded by the national natural science fund titled "Integration and Systematization of Mathematic Models for Soil and Water Resources Study in a Basin and its Application", The model is developed to simulate the runoff and sediment yield of a small watershed and its frame is preliminarily built for simulating the processes of interception , snowmelt, infiltration , overland flow procerdure, groundwater flow, channel flow, water routing and sedimentation routing.The Main countents and research results are as follows:(1 )The characteristics and the development of models and simulation technology were systematically studied in this dessertation. The application of Basin simulation integrated with RS ans GIS technology was fully explained from theory to practice. It was proved by the practice that the integration of basin models, RS and GIS is indispensable for basin simulation technology shifting from thd lumped to the distributed system.(2) The method of distributed hydrological modelling based on raster Digital Elevation Models (DEM) was applied to generate basin network, to divide sub-basin and generate basin boundary automatically. 102 discrete sub-basins and 649 Hydrological response units were produced in the study area .(3)Parameters for model running including topography, soil, climate and land use were extracted by means of RS, GIS and statistics methods using present data of study area, spatial parameterization process of the basin was successfully realized and soil parameters calculation, temperature , precipitation spatial correction and land use supervised classification were studied in this dissertation.(4)The model parameters extracted from the GIS parameterization were managed in the database. According to the model reuqirement, the database fields were set up corresponding to the contents of parameters and tables relevant to spatial features were solved. According to the grading spatial integration of the simulation results were gradually realized.(5)Computer aided simulation of multi-geographical process in Lianshui basin was carried out using data of 10 years and quantivative simulation results were obtained. The simulation accuracy of annual water yield for spatial scales was above 88.55% and best simulation accuracy of monthly water yield was also above 81.80%. But the simulation accuracy of annual and monthly sediment yield were both unacceptably.(6)Since the distributed hydrological model can simulate the changes of water and sediment with the time and space in watershed, it is more advantaged than lumped model for the planning and improvement of soil and water conservation and calculating and forecasting the non-point pollution, etc. As the improvement and combinagion of GIS and RS technology, the distributed hydrological model will show a wide utilization in the future.
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