基于概率数学方法与GIS的泥石流敏感性分析及评价——以汶川县为例

以汶川县为研究区,通过对震后的高分辨遥感影像的遥感解译,获得了145条泥石流沟及流域中的崩滑物源的分布图。选择了坡度、坡向、地层岩性、地震峰值加速度、距水系距离、距断层距离作为评价因子,利用概率数学方法与GIS的空间分析功能,获得145条泥石流沟在上述6个评价因子上的分值;再利用层次分析法计算得到各评价因子权重,建立泥石流敏感性评价模型,得到了研究区泥石流沟敏感性分级图。结果表明:研究区145条泥石流沟中,有60条泥石流沟属于高敏感性,43条泥石流沟为中敏感性,其余42条泥石流沟敏感性较低,研究成果对于认识该地区泥石流灾害现状及发展趋势与防灾减灾有一定的参考意义。

Susceptibility Assessment of Debris Flow Using a Probabilistic and GIS Approach: A Case Study on the Wenchuan County

In this paper we mapped co-seismic landslides and potential source materials for generating debris flows in 145 catchments based on high resolution satellite images in Wenchuan County.Slope,aspect,lithology,peak ground acceleration,distance to drainage,distance to faults were used as factors for debris flow susceptibility analysis.Probabilistic mathematic method,spatial analysis,analytic hierarchy process,and weight analysis were applied to generate a debris flow susceptibility map.Our result indicates that 60,43,and 42 catchments were highly,moderately,and lowly susceptible to debris flow respectively.The results offer reference for the debris flow research and mitigation planning of the area in the future.