基于GIS的上海市嘉定区暴雨积涝灾害风险区划研究

GIS-based Risk Zonation of Flood Disasters in Jiading District of Shanghai

根据2006-2012年上海嘉定区9个气象站点的小时降水资料,结合嘉定区的社会经济与自然地理要素,构建一个集致灾因子、孕灾环境、承灾体及防灾减灾能力为一体的区域暴雨积涝风险评价模型。通过GIS技术实现各指标的栅格化,并利用指数模型对各因子基于500 m×500 m栅格的基本单元进行计算,编制嘉定区的暴雨积涝灾害风险区划图,构成嘉定区五个等级的风险,分别为高、次高、中等、次低和低。区划结果表明嘉定区的暴雨积涝灾害危险性指数从中心向外围成递减的趋势,且嘉定镇、新城和工业南区相对风险较高,华亭、徐行、南航和江桥风险相对较低。经嘉定区历年暴雨积涝灾情资料、典型暴雨积涝案例和专家的验证,均表明风险区划的结果和实际灾情符合度较高,对嘉定暴雨积涝的防灾减灾具有重要的现实指导意义。

Based on the precipitation data from nine meteorological stations in Jiading District of Shanghai during 2006 to 201 2 and combined with the society economic and nature geographic factors,a set of flood disaster assessment model,including hazard factors,hazard inducing environment,hazard-affected body and disaster pre-vention ability,is built.And a map of flood disaster risk division in Jiading is drawn using 500 m ＆#215;500 m raster as basic assessment unit,by means of GIS spatial analysis technique for rasterizing evaluation indices and fuzzy com-prehensive assessment methods.Finally,the five risk zones of Jiading,higher risk,sub-high risk,medium risk, inferior risk and lower risk,are mapped.Results show that flood disaster risk is of a decreasing trend from center to periphery.Jiading town,Xincheng town,South industrial district and so on,have relative high risk,while Huating town,Xuhang town,Nanhang town,Jiangqiao town and so on,have slightly lower risk.The rainstorm waterlogging disaster,evaluation of typical rainstorm waterlogging and experts indicate that the risk zoning result basically accord with the actual situation,it has important practical significance for disaster prevention and mitigation in Jiading rainstorm waterlogging.