Setting-up And Application Of The Geological Calamity Database In Wenzhou On The Basis Of ArcGIS

Wenzhou is one of those areas that geological calamities frequently occur in our country. Geological calamities lead to enormous losses to local people's lives and properties, such as landslide, mud-rock flow, etc. In order to set up a Forecasting and Early-warning System and put it into practice, and on the basis of geology investigation of all the areas and counties of Wenzhou, this research analyzes the assessment factor of the risk appraisal of geological calamities and its grading standard, thus, the database and forecasting information system of geological calamities of Wenzhou have been set up, which is based on ArcGIS. Therefore, this research is very significant to both theory and practice of the development of the geological calamity prevention of Wenzhou.On the basis of general design of the database of geological calamities, the graphics database has been set up with the outstanding international software ArcGIS as the base platform in the research. Meanwhile, we also set up the property database with Microsoft Access, as a result, the graphics database and the property database are combined together with the calamity coding set up in the two databases. With the module of Spatial Analyst of ArcGIS, we can distill the assessment factor of the risk appraisal of geological calamities, then after superposing these assessment factors, we can give a grading of them with the method of zonal statistics, thus, according to the principle of fuzzy comprehensive evaluation and the grading standard of he assessment factor of the risk appraisal of geological calamities, as well as the weight of each assessment factor given by many experts, the value of each assessment cell can be calculated with the VB procedure design by the author. Then, after giving its value to each assessment cell of the profile of Wenzhou with ArcMap, the distribution map of risk appraisal of geological calamities can be gained.In this research, on the basis of the secondary development of VB6.0 and ArcObjects, the forecasting information system of geological calamities of Wenzhou is set up. In this system, the distribution map of risk appraisal of the landslide and the mud-rock flow of every rainfall can be gained, according to the analysis of the risk appraisal based on the fuzzy comprehensive evaluation and the rainfall. What's more, according to the forecasting information system, we can offer a query system of the data information of the graphics and the property of the landslide and the mud-rock flow.