Development And Implementation Of A Distributed Hydrological Model Based On MapWinGIS

In support of open source GIS, this article put forward a method that how to build a distributed hydrological mode which was based on both saturation excess and infiltration excess mechanisms. Large scale distributed hydrological simulation system based on sub-basin was designed and constructed for the study of hydrological processes. At the same time, this paper had done the work which simulated the hydrological processes in different scenes. And the result could provide decision support for flood forecast, water resources management.In this paper, the research focused on the following four aspects:1,This paper had introduced and explored the open source platform MapWinGIS. The platform was widely applied in kinds of field in the worldwide.2,This paper had put forward a method how to build the distributed hydrologic model.The method had adopted modular programming ideas. In the model, the hydrological processes of watershed are divided into evapotranspiration module, runoff module and flow module.3,Large scale distributed hydrological simulation system based on sub-basin was designed and constructed. The open source GIS platform was MapWinGIS.The language in which we use to program was C#, and the system adopted plug-in technology. In the system, the hydrological processes of watershed are divided into evapotranspiration module, overland runoff module, interflow module, groundwater runoff module and flow concentration of river channel module. The hydrologic model had provided multiple runoff models and confluence models.4,Take Huaihe and Ganjiang River as the research area, simulate the hydrological processes, analyze the flood processes and simulate the hydrological processes in different scenes. This study had extracted the hydrographic net and sub-basin based on DEM. The information was used as input parameters for the model. This paper had analyzed the effects of reservoirs and soil humidity to flood processes. The result showed that, firstly, the reservoirs had the only function of dammed-up. The floodvolume and flood peak was cut obviously. Secondly, the results of simulation were proportional to the soil humidity; the greater the humidity was, the bigger the simulation value was.The result showed that large scale distributed hydrological simulation system based on sub-basin had the following advantages:firstly, it was based on the DEM data. And the computing unit was the sub-basins whose underlaying condition was similar. The hydrological processes among the computing units became very simple and clear, and it also could simplify the calculating methods of the traditional hydrological model. Secondly, the system considered the influence on the hydrologic processes of human activities. The simulation result could accurately reproduce the hydrologic processes. Thirdly, the system could accomplish the hydrological simulation in different weather and underlying surface conditions. Finally, the users could improve the calculating methods or add their own functional module according the project.