藏东南地区属高原地区，山势险峻，复杂的地形地貌诱发地质灾害的发生，加大工程建设的难度。为分析研究区滑坡灾害的易发性，选取8个评价因子(与道路距离、与水系距离、高程、坡度、坡向、工程地质岩组、土壤类型、地表覆盖)为量化指标，以层次分析法确定权重值，同时借助ArcGIS得到加权信息量模型和加权确定性系数(certainty fator，CF)模型，对比选取准确度高的滑坡灾害评价模型，运用受试者特征曲线(receiver operate curve，ROC)验证结果准确性。研究结果如下:①加权CF模型的受试者特征工作曲线下的面积(area under receiver op-erating characteristic curve，AUC)值高于加权信息量模型AUC值，加权CF模型结果覆盖滑坡点多于加权信息量模型，研究区滑坡易发性评价选取加权CF模型分析结果更加准确;②加权CF模型将研究区滑坡易发性评价结果划分为高易发区、较高易发区、中高易发区、较低易发区、低易发区，其中高易发区主要分布在墨脱县和贡觉县，较高易发区分布在卡若区、芒康县，中高易发区分布在类乌齐县、丁青县、江达县，较低、低易发区分布在巴宜区和朗县等。滑坡易发区的划分可为该区域的工程建设提供决策依据。
Landslide susceptibility assessment in the southeastern Tibet based on weighted informativeness and weighted certainty factor
The southestern Tibet is a plateau region with steep mountains.The complex topography and geomor-phology would easily induce geological disasters and increase the difficulty of engineering construction.In order to analyze the landslide susceptibility in this area,the authors in this paper selected eight evaluation factors as quan-titative indexes,including distance from road,distance from water system,elevation,slope,slope direction,en-gineering geological rock group,soil type,and surface cover.The weighted value was determined by analytic ni-erardty process,and weighted informativeness model and weighted certainty factor(CF)were obtained by Arc-GIS.Finally,the receiver operate curve was adopted to verify the accuracy of the results.The research vesullts are as follows(1)The AUC value of the weighted CF model is higher than the AUC value of the weighted inform-ative ness model,and the covered landslide points from the weighted CF model the than those from the weighted informative ness model.So,the weighted CF model is more reliable in assessment of landslide susceptibility in this area.(2)The susceptibility zone is divided into high,relatively nigh,medium-high,relatively low,and low susceptibility zones by weighted CF model.The high susceptibility zone is mainly distributed in Mutuo and Gongjue counties,and relatively high susceptibility zone is distributed in Karuo and Mangkang counties.The me-dium-high susceptibility zone is distributed in Qiangwuqi,Dinching,and Janda counties,and the relatively low and low susceptibility zones are distributed in Bayi and Lang counties.The delineation of landslide-prone areas could provide some decision-making basis for the engineering construction in the region.
万方数据
维普
