基于GIS技术的重庆市暴雨洪涝灾害风险区划研究

The Study of Risk Zoning of Rainstorm and Flood Disaster Based on GIS in Chongqing

为了定量地研究分析重庆暴雨洪涝灾害风险和区划,利用重庆1961—2008年的气象观测资料,综合全市各区县的自然、社会经济与防灾抗灾等数据,利用GIS技术和自然灾害风险指数,构建暴雨洪涝灾害风险评价模型,对重庆市暴雨洪涝风险的致灾因子危险性、孕灾环境敏感性、承灾体易损性、防灾抗灾能力多个因子定量分析,计算得到重庆市区县级暴雨洪涝灾害综合风险指数,并绘制了风险区划图。结果表明:重庆的开县、梁平、合川、北碚、荣昌、永川、渝北及铜梁部分地区的危险性和易损性指数较大,其暴雨洪涝灾害风险最大;南川、丰都与石柱、黔江、涪陵、綦江部分地区由于暴雨洪涝发生频率较低,孕灾环境敏感性指数较小,灾害风险最小。

In order to quantitatively research the rainstorm and flood disaster risk and zoning in Chongqing,according to 1961 — 2008 meteorological data in Chongqing,integrating with natural,socio-economic and disaster prevention and reduction factors in each district,based on geography information system,methodology of flood disaster risk index and constructed model of rain and flood disaster risk assessment,the flood disaster risk indexes were calculated and risk zoning maps were worked out for every county of Chongqing by analyzing hazard,sensitivity,vulnerability and emergency response and recovery capability of the counties.The results indicated that the possibility of rainstorm and flood risk was the biggest in Kaixian,Liangping,Hechuang,Beibei,Rongchang,Yongchuan,Yubei and partial area of Tongliang,because the indexes of the expositions and the hazard of these areas were relatively higher.Whereas Nanchuang,Fengdu and partial areas of Shizhu,Qianjiang,Fuling,Qijiang had the least flood risk due to lesser disaster environmentally sensitive indexes and torrential rain frequency.