白龙江流域基于GIS与信息量模型的滑坡危险性等级区划

Landslide susceptibility mapping based on GIS and information value model in Bailong river basin

利用Rivertools提取流域边界,基于野外调查及在前人研究基础上,选取起伏度、坡度、坡向、岩性、降雨、植被覆盖、土地利用等11个与滑坡发生相关要素作为危险性评价因子.在GIS环境下,采用经验似然比的数据分类方法,运用信息量模型,绘制了研究区的滑坡灾害危险性等级区划图,最后利用15个活动滑坡对模型精度进行检验.研究结果表明:根据区划图,白龙江流域可分为5个区域:极高危险区、高危险区、中等危险区、低危险区、极低危险区,所占研究区面积比例分别为21%,26%,37%,11%,5%.活动滑坡都位于等级很高和高的区域内,说明模型评价结果与研究区实际情况吻合.

The catchment boundary was extracted by utilizing Rivertools software. Based on filed investigation and previous research, eleven elements including relief amplitude, slope, aspect, lithology, precipitation, NDVI, land use and so on that contribute to the occurrence of landslide were selected as the risk evaluation factors. Under the circumstances of GIS, adopting the likelihood ratio as data categorizing method, then using the information value model, the landslide susceptibility map was established. Finally, 15 active landslides with sliding displacement were utilized to validate the accuracy of the model. According to susceptibility map, the study area was classified into five categories, i.e., very high dangerous zone, high dangerous zone, moderate dangerous zone, low dangerous zone and very low dangerous zone, taking an area proportion of 21%, 26%, 37%, 11%, 5%, respectively. All active landslides zone fit into the very high and high susceptibility classes. The results showed that the information value model corresponded to the actual distribution of landslides susceptibility in this area.