Design And Realization Of The Early Warning System Of Geological Hazard Risk In Wenzhou On The Basis Of ArcGIS

Wenzhou is located in the coastal area of southeast China of Zhejiang, geological structure and geographical environment are complicated, especially the strong rainfall of the period of typhoon, extremely apt to cause the emergence of the geological hazards such as collapse,landslide and debris flow, it is the geological hazards to occur frequently area. But the traditional methods of geological hazard assessment have been unable to meet the needs of disaster prevention and reduction of Wenzhou, because of their low efficiency and precision. For the losses caused by the geological hazard are minimized, we need find a new method for the early warning of the geological hazard risk of Wenzhou.This study based on the ArcGIS technology , on the basis of comprehensive analysis of the formation background of geological hazards,environmental characteristics,main affecting factors and data of geological hazards in Wenzhou in the past years , at first this thesis analyzes the system requirements and objective, analyzes and designs the overview structure of the system, the scheme of system development, the functions and database, by using the design methods of structure and module. Then we proofread and amend the pre-established database to accord the design requirements , add 1km×1km raster data of each affecting factor to database; write calculation module of risk assessment factors by Visual C++; adopt AHP and fuzzy method to judge synthetically, set up the dynamic appraisal model of geological hazard of Wenzhou based on rainfall once; then on the basis of those work, the early-warning system of geological hazard risk of Wenzhou had been set up in Microsoft Visual Studio 2005 by suing Visual C++ and Arc Engine. In order to verify the system, this thesis chooses two rainfall data which are September 4 1999 and August 13 2004 in the end.Wenzhou geological hazard dangerous pictures of dividing of the two rainfall have been created by the system, simultaneous contrast two rainfall these hazards produced order, it take place actually order hazards mostly fall into districts dangerous high turning into in system or in districts dangerous, its result is satisfactory. The Wenzhou government can use it as decision support system of geological hazard prevention. The early-warning system of geological hazard risk of Wenzhou is simpler, more effective and accurate than the traditional method for geological hazard assessment; it can meet the need of the early warning of the geological hazard risk of Wenzhou.