Study On Integration Of GIS And Water Quality Evaluation And Prediction Model

Prevention and control of water pollution in the Three Gorges reservoir area are facing an urgent task after the completion of the Three Gorges reservoir area. As a collection, storage, management, application and analysis of the modern tools of geographic information, GIS has become the essential instrument to manage and use of space-related information. The integration between GIS and water quality models has become one trend of the water quality forecasting system.This paper relies on a major research project of Chongqing Science and Technology Commission. The project named"Early warning platform of water environment security in the Three Gorges reservoir area"(No.CSTC2006AA7024). The implementation of GIS and water quality models was based on MapObjects and Visual C++.First of all, an analysis of water quality evaluation and prediction models in the research and application of the status quo at home and abroad. This paper focuses on the single-factor evaluation of water quality, water quality index and other water quality evaluation methods. In terms of water quality prediction models, this paper studied on one-dimensional hydrodynamic model and BOD-DO model which are used in water quality prediction. Though water quality models have strong calculating function when modeling water quality, it's difficult to show their modeling results, however, using GIS can solve this difficulty.Secondly, there is an introduction of the secondary development of geographic information system methods. Focus on the method, property and class in the MapObjects. And then, this paper studies on the integrated route and method of implementation between water quality models and GIS.Finally, the realize technology is used in the"Early warning platform of water environment security in the Three Gorges reservoir area". Achieve the implementation of the information entry, data processing, the output of the results and many other features. Use the water quality index to evaluate the level of the water. Show the different level of the water quality through the different color. Use one-dimensional hydrodynamic model and the BOD-DO models to achieve the water quality prediction. Predict the water concentration on different locations at different time. All of this can better meet the water quality assessment, trend analysis and other functional requirements.This paper not only makes up for the shortcomings of water quality models, but also exerts sufficiently GIS's advantages of spatial analysis and data management. This research of combining water quality modeling and GIS technology is just a primary try and exploration; it has some significance for some work in this field and can influence the further research of combining more complicated water quality models with GIS technology.