基于主成分分析的城市内涝灾害风险评估--以杭州市临安区为例

Risk Assessment of Urban Waterlogging Disaster Based on Principal Component Analysis:An Example of Lin an District of Hangzhou

城市内涝灾害风险评估对灾害预警和风险防范具有重要指导意义.结合灾害风险理论,以浙江省杭州市临安城区为例,选取致灾因子危险性、孕灾环境敏感性、承灾体易损性及防灾减灾能力等代表性指标,采用GIS空间分析和主成分分析方法进行风险评估,最终生成以200 m×200 m栅格为基本评价单元的城市内涝灾害风险评估结果.结果显示:临安城区总体内涝风险较低,高风险区域面积约占3.9%,零散分布于锦城街道、玲珑街道等老城区低洼地带;青山湖街道等部分新城区受城市建设尚未完成的影响,风险等级相对较高.

Risk assessment of urban waterlogging disaster has great guiding significance for the early warning and risk prevention of the disaster.Combining with the disaster risk theory and taking urban area of Lin an district as the example,the representative indicators such as hazard formative factors,sensitivity of disaster environment,vulnerability of disaster-bearing bodies,and capabilities of disaster prevention and mitigation were selected.The risk assessment was carried out by means of GIS spatial analysis and principal component analysis,and the final report of urban waterlogging disaster risk assessment was generated with 200 m×200 m grid as basic evaluation unit.The results showed that the overall risk of waterlogging in Lin an was relatively low.The high-risk areas accounted for about 3.9%,which were scattered in low-lying areas of old urban areas such as Jincheng Street and Linglong Street.Some new urban areas,such as Qingshan Lake Street,showed the relatively higher risk level due to the uncompleted urban construction.