城市泥石流风险评价探讨

探讨了城市泥石流风险评价的系统方法,该方法包括泥石流扇形地危险区划、城市易损性分析和城市泥石流风险评价三个主要内容。泥石流堆积扇危险区划是基于数值模拟计算出的泥深和流速分布图进行叠合完成的。以美国高分辨率的“快鸟”卫星影像为数据源,完成了研究区的城市土地覆盖类型遥感解译,在此基础上完成了城市泥石流易损性分析,应用地理信息系统提供的统计和分析工具,完成了研究区泥石流风险评价。该风险区划图可用于指导对泥石流易泛区的不同风险地带的土地利用进行规划和决策,从而达到规避和减轻灾害的目的,也为生活在泥石流危险区的城市居民提供有关灾害风险信息,以作避难和灾害防治的依据。

Approach for urban debris flow risk assessment

This paper researches the integrated method of urban debris flow risk assessment.The method involves the debris flow hazard zonation,the urban vulnerability evaluation and the risk assessment.The debris flow hazard zonation on the alluvial fan of the study area is caused by overlaying the distributed flow depth and velocity maps,which are produced through the numerical simulation.The detailed land cover information is derived by using the Quickbird high spatial resolution satellite imagery,and then we evaluate the vulnerability value through the different land-use features.Based on a GIS statistical and analytical tool the urban debris flow risk assessment for the study area is completed.This risk zonation map can be used for the debris flow mitigation by identifying hazard prone areas allowing for the avoidance through zoning or other land use polices,and provide risk information for the residents who live in the debris flow prone areas in order to plan the evacuation and prevention.