基于GIS技术和频率比模型的三峡地区秭归向斜盆地滑坡敏感性评价

LANDSLIDE SUSCEPTIBILITY ASSESSMENT IN THE THREE GORGES AREA,CHINA,ZIGUI SYNCLINAL BASIN,USING GIS TECHNOLOGY AND FREQUENCY RATIO MODEL

以三峡地区秭归向斜盆地为研究区,在野外滑坡编图的基础上,选择地形坡度、地层岩性、河流、道路、坡向、坡型结构6个因子参与滑坡敏感性评价,运用GIS空间分析技术,引入频率比模型,分别计算评价因子的贡献率,并进行叠加分析,最终划分为4个敏感性分区。评价结果表明:极高敏感性区面积占21.39%,滑坡发生面积占61.44%;高敏感性分区面积占24.99%,滑坡发生面积占21.67%;中敏感性分区面积占30.66%,滑坡发生面积占13.19%;低敏感性分区面积占22.93%,滑坡发生面积占3.69%。滑坡敏感性面积累计百分比曲线图表明评价结果具有较高的准确度和可靠性。研究成果可为政府部门减灾防灾工程提供科学支持,为滑坡灾害的预测和管理提供科学依据。

The Three Gorgesarea, China, Zigui synclinal basin is selected as a case study in this paper. Based on the field of landslide mapping,in the frequency ratio model, slope angle,lithology, rivers, roads,aspect and beeding-aspect this six assessment factors are considered to assess landslide susceptibility by overlaying analysis using GIS technology to calculate the contribution rate separately, Ultimately, landslide susceptibility area is divided into four partitions. The results shows that the vey high susceptibility area accounts for 21. 39 percent and landslide area accounts for 61. 44 percent, high susceptibility area accounts for 24. 99 percent and landslide area accounts for 21. 67 percent. Moderate susceptibility area accounts for 30. 66 percent and landslide area accounts fori3. 19 percent. Low susceptibility area accounts for 22. 93 percent and landslide area accounts for 3. 69 percent. The cumulative percentage curve of landslide susceptibility area shows that the results are highly accurant and reliable, what to provide scientific support for the government about disaster prevention and reducing engineering , and provide scientific basis to landslide forecast and management.