The Study Of Jinhua Debris Flow Risk Evaluation System Based On GIS

Debris flow risk evaluation is primarily used for the delineation of the regional debris flow danger rating and assessment of potential human and property losses caused by disasters and is an important non-engineering measure in the prevention and treatment.The results of the evaluation has an important reference value in government decision-making, project for disaster prevention and reduction, major projects, as well as local economic development.The applications of RS and GIS technology in the process of debris flow risk evaluation greatly improves the efficiency of the evaluation and accuracy of evaluation results.Took Jinhua in Zhejiang Province as a study area, based on GIS Second Integrated development technology, tried to complete the design and implementation of the debris flow risk evaluation system and complete the debris flow risk evaluation of Jinhua based on the remote sensing images, DEM, land use maps and field survey data and the system as a tool, got and analysed the evaluation results.The main work and conclusions are as follows:1,Completed the design of debris flow risk evaluation system. It is in C/S mode, using GIS Second Integrated development technology, ArcGIS Engine as GIS software tool, VS 2005 as visual development tool. primarily functional modules included documents functional modules, map browsing and selection, data acquisition module, edit and Query Module, 3D display module, factor analysis and spatial analysis module, assisted modeling module, map output module.2,Completed the implementation of debris flow risk evaluation system, the main function included the basic functions of GIS, the realization of geographical environment to achieve the 3-D display function, factor analysis and spatial analysis functions, and supporting the realization of the achievement of functional modeling. GIS basic functions achieved the functions of the data display, data acquisition,features editing, as well as map output. The 3D display of Geographical features function achieved function of displaying remote sensing images and vector data with the superposition of DEM, display settings, roaming, flight capabilities. Factor analysis and spatial analysis functions achieved function of correlation analysis, sensitivity analysis, slope analysis, watershed area extraction, statistical analysis, raster calculating capabilities. Assisted modeling function achieved the functions of organizing and displaying the process of model.3,Through field study and analysis of the display system, identified the evaluation cell,influence factors and evaluation model of the hazard assessment and vulnerability assessment of the study area ,completed the hazard assessment and vulnerability assessment,got the results to analyse. The result of hazard assessment show that it was very consistent with the history of debris flow in this area.On this basis, the result of risk evaluation was get and it show that the northern hills and low mountains zone is most risky and the intermontane basin zone is least risky. Although the southern hills and low mountains zone had more dangers,it is less risky than the northern hills and low mountains zone because of its less vulnerability.So the northern hills and low mountains zone should be as priority monitoring zone, and on this basis , necessary management and improvement should be carried out to enhance the resilience against] the debris flow. In the region of greater risk, protection and improvement of ecological environment and vigorously afforestation is needed. Through forest cover to reduce surface runoff and water and soil loss, so can reduce the frequency of debris flow caused by heavy rain.