四川省雅江县上游河段滑坡灾害危险性评价

雅江县位于四川省西部雅砻江中游河段，以中山-高山峡谷地貌为主，地质灾害频发.为保障人民生命财产安全，基于逻辑回归与确定性系数叠加分析，进行雅江县上游河段滑坡灾害危险性评价.结果表明：1）雅江县上游河段滑坡极易发生在海拔2 500~3 000 m、拔河高度600~900 m、坡度30~45°、距离河流水系0~200 m范围较硬岩夹较软岩类地带；2）雅江县上游河段高危险区、极高危险区面积占总面积的46.75%，发生滑坡占滑坡总数的65.91%，说明该区域内滑坡分布密集，危害程度相对较高，与野外实际调查结果相符；3）雅江县上游河段呷拉镇一带多属极高危险区、高危险区，瓦多乡一带多属中等危险区，木绒乡、普巴绒乡一带多属低危险区、极低危险区；4）通过查验点及ROC曲线对评价结果验证，该评价结果有较高的准确性，能够作为研究区防灾减灾与河谷开发利用的合理方案依据.

RISK ASSESSMENT OF LANDSLIDE DISASTERS IN THE UPPER REACHES OF YAJIANG COUNTY,SICHUAN PROVINCE

Yajiang County, located in the middle reaches of Yalong River in western Sichuan Province, is dominated by the landform of middle mountain-alpine valley, with frequent geological disasters. The risk assessment of landslide disasters in the upper reaches of Yajiang County is carried out on the basis of overlay analysis of logistic regression (LR) and certainty factor (CF) to ensure people's life and property security. The results show that the landslides are prone to occur in the hard rock interbedded with soft rock zone, with an altitude of 2 500-3 000 m, relative height above river of 600-900 m, gradient of 30-45° and distance of 0-200 m from river system. The high and very high risk areas in the upper reaches of Yajiang County account for 46.75% of the total area, and 65.91% of the total landslide occurrences, indicating the dense distribution of landslides and high damage degree, which is consistent with the field survey results. The Xiala Town mostly belongs to very high and high risk area, Waduo Township mostly medium risk area, and Murong Township and Pubarong Township mostly low and very low risk area. The assessment results have high accuracy through verification of inspection points and ROC curve, and thus can serve as a reasonable plan basis for disaster prevention and mitigation, river development and utilization in the study area.