Combine Research Based On The DBMS Of Delphi And WEPP Model

Soil erosion forecast model can be used for the simulation of the soil erosion process, calculate the erosion intensity and the analysis of the environment and formation. It will provide important way and technical support for the degenerative zoology and sustainable development for human being. Water erosion is the most distributed and jeopardized type in the world. In recent years,most research for the erosion module have all against this. So far WEPP model as the new generation one, it has the largest amount parameter and most complicated computer process.and it can do the evaluation both from the space and time way; reflecting the erosion distribute and simulating the erosion transportation process. Water and soil conservation information manage and analysis system, base on the computer platform and net environment, use the advanced special technology for the traditional watershed management and conservation measure information reconstruction. The system can share the data, improve the work efficiency, simplify the process, decline the cost with water resource, environment and weather ministry. All of these can standardize the data storage system, improve the utilization, construct the share platform, drive the water and soil conservation to the modernization. The research bases on the WEPP water erosion forecast model, according the soil and Water Conservation Stations primary database management system of Delphi, to develop a new database management system(DBMS). At the same time use this new system to evaluate the Yangtse river purple soil hilly area. The results shows that,the secondary development of this system is feasible, which can make the WEPP and database have a good combination. Further more it will provide the better service for the monitoring and forecast analysis which also can be used for the measure and information design in the three gorges area.the research includes:part one:develop a new system can both satisfy Soil and Water Conservation Stations primary database daily use and forecast with advanced analysis information. Completion as the following:(1) Use the MFC to edit the WEPP relevant weppin module.(2) Achieve the WinAPI cross process transfer through the weppin according on the Delphi language about the VC++.(3) Achieve the WEppin module which involve the list and line control; snatch button window in the Weppin.(4) Use the weppin module set in the primary water and soil conservation database system, pick up the WEPP relevant function in the main computer interface, also make the WEPP run in the background then shows the result.part two:test and validate the new system in the stability and availability, take the single rain in the purple soil hilly area as example to analysis the data.(1) Integrate the part about the "suining water and soil conservation station information manage analysis system" make the WEPP can be stablely and smoothly used in the original system interface.(2) On the same condition of the slope, for the rainfall runoff, the WEPP model validity ME 0.856,R2 0.9089; for the rainfall soil erosion the validity ME0.616, R2 0.8446.the results shows the module has a good simulation and proximity of the rainfall erosion process. Runoff simulation model is relatively better than the accuracy of the simulation accuracy of soil erosion.(3) WEPP model system about the runoff simulation accuracy is better than the soil erosion simulation accuracy.(4) WEPP model in the system has better reliability simulation of the big runoff sediment than the simulation of the small runoff sediment. During the simulation,the runoff reliability is better than the sedimentyield.