金沙江流域内滑坡灾害频发,对大型工程及交通设施均造成了极大的损害.采用确定性系数(CF)与证据权(WOE)模型,选取坡度、坡向、NDVI、海拔、岩石性质、纵剖面曲率、距道路的距离、距河流的距离、距断层的距离与第四纪沉积物类型10个指标,分不同组合进行区域性滑坡灾害敏感性评估.CF与WOE在多种不同指标组合下经过累积频率曲线下面积(AUC)检验,结果表明10种指标组合下的CF模型表现最佳,相比WOE模型所得的最高准确率(74.52％)与预测率(69.89％),CF的准确率与预测率分别高达83.40％与74.43％.CF计算获得的敏感性指数通过自然间断点法将研究区域分为滑坡极难发生区、滑坡较难发生区、滑坡较易发生区与滑坡极易发生区4类区域.评估结果指示程海断裂带南北延伸带与金沙江中段主要干支流沿线为区域的滑坡灾害易发区,表明断裂带及河流与该区域的滑坡发生具有一定的相关性.%For the high frequency of landslide occurrences in the watershed of Jinshajiang,certain factor (CF) and weight of evidence (WOE) were both adopted to evaluate landslide susceptibility in this area.In this study,ten variables were selected to combine diversely in the process of modeling,including slope,aspect,normalized difference vegetation index,altitude,lithology,profile curvature,distance to roads,distance to rivers,distance to faults and the types of Quaternary sediments.Validated by the area under the prediction rate curve (AUC),the results indicated that CF with the total l0 variables had the best performance among the two models with combinations of various variables.The succeed rate and predictive rate of CF with the 10 variables respectively reached to 83.40％ and 74.43％,while the results of WOE merely reached to 74.52％ and 69.89％.It is proved that CF has high accuracies in both experiment area and verification area.Thereafter,the landslide susceptibility index generated from CF was further categorized into 4 subdivisions by the natural-break classification,including extremely difficult,moderately difficult,moderately easy and extremely easy area to landslide occurrences.As shown in the result of classification,either the north-south extended zones of the Chenghai Fault or the areas along the middle segment of Jinshajiang are prone to triggering landslides.The result implied a special correlation among faults,rivers and landslide occurrences.
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