基于确定性系数模型的泸水市泥石流易发性评价

Assessment on Susceptibility of Debris Flow in Lushui Based on the Certain Factor Model

以泥石流灾害频发的怒江州泸水市为研究区,选取坡度、高程、河流距离、道路距离、岩性、断裂带距离、降雨量、NDVI、土地利用9个影响因子,建立了泸水市泥石流灾害易发性评价体系。采用确定性系数模型(CF模型)进行了泥石流灾害易发性评价,将泥石流易发性评价结果分为极高易发区、高易发区、中易发区、低易发区4个等级。结果表明:研究区高易发区及以上级别的易发区内发生的泥石流灾害数量占总数的95.32%,易发性评价结果正确率达到81.99%,表明选取的评价指标合理,CF模型适用于泸水市的泥石流灾害易发性评价研究。泸水市泥石流灾害高易发区也是居民点集中分布区,评价分区结果对泸水市的泥石流灾害防灾减灾具有一定的借鉴作用。

Lushui City,Nujiang State was taken as the study area,where debris flow occurs frequently.Nine impact factors including slope,elevation,river,road,lithology,fault,precipitation,NDVI and land use were selected to build the susceptibility assessment system.The certain factor model(CF model)was used to evaluate the susceptibility,result of which can be divided into 4 areas of extremely high susceptibility,high susceptibility,middle susceptibility and low susceptibility.The results showed that the events of debris flow occurred in the area which had a susceptibility above high accounted for 95.32%of the total debris flow events,the correct rate of susceptibility evaluation results reached up to 81.99%,indicating that selected indices were reasonable and CF model was practicable in susceptibility assessment.The high susceptibility area of debris flow in Lushui City was also the distribution area where settlements were concentrated.Therefore,the evaluation results could provide the reference for debris flow disaster prevention and mitigation in Lushui City.