基于地理信息系统和加权信息量的茂县地质灾害易发性评价

Geographic Information System and Weighted Information Value Assessments of Geologic Hazards in Maoxian County,Sichuan

以茂县为研究区,选取坡度、起伏度和道路等8个因子构建评价指标体系,通过信息量法、确定系数法确定因子信息量值和权重,运用ArcGIS进行地质灾害易发性评价。结果显示,研究区高易发区面积345.62 km^(2)、较高易发区456.65 km^(2)、中易发区664.83 km^(2)、较低易发区943.71 km^(2)和低易发区1488.34 km^(2),分别占总面积的8.86%、11.71%、17.05%、24.20%和38.17%。对评价结果进行合理性检验和受试者特征曲线(receiver operate curve,ROC)的精度检验,检验结果表明评价具有合理性,且曲线下的面积(area under curve,AUC)值为0.882,即评价准确度较好。研究结果能为研究区的灾害防治和国土空间规划提供科学依据。

Taking Maoxian County as the research area,eight factors including slope,relief and roadway etc.were selected to construct an evaluation index system.The information quantity method was used to determine the value of the factor information,and combined with the determination coefficient method to determine the factor weight,the ArcGIS was used to carry out the geological disaster susceptibility evaluation.The results show that the high-prone area in the study area covers an area of 345.62 km^(2),a high-prone area of 456.65 km^(2),a medium-prone area of 664.83 km^(2),a low-prone area of 943.71 km^(2),and a low-prone area of 1488.34 km^(2),respectively accounting for 8.86%,11.71%,17.05%,24.20%and 38.17%of the total area.The rationality test and receiver operate curve(ROC)accuracy test of the evaluation results show that the evaluation is reasonable,and the area under curve(AUC)value is 0.882.That is,the evaluation accuracy is relatively better.The research results can provide a theoretical basis for disaster prevention and mitigation,monitoring and early warning,and land and space planning in the study area.