基于关键驱动力的怒江州兰坪县泥石流危险性评价

近年来,云南怒江地区多次暴发大规模灾害性泥石流,造成了重大人员伤亡和财产损失.文章选取矿产和水电资源丰富的兰坪县泥石流为研究对象,通过现场勘察,结合已有调查成果,明晰兰坪县泥石流空间分布格局;在此基础上,从地质驱动力、水动力和重力驱动力3方面构建基于关键驱动力的单沟泥石流危险性评价指标体系,运用层次分析法与GIS技术开展危险性评价.结果显示:兰坪县境内79条泥石流沟中,处于高危险性的有20条,中危险性30条,澜沧江右岸和左岸分别为高危险性和中危险性泥石流沟的集中区.进一步分析表明,兰坪县泥石流危险性高低受降水影响较大,从澜沧江右岸到左岸再到通甸河,降水逐渐减少,泥石流的危险性也逐渐降低;本研究结果可对兰坪县大型工程建设及保障运营安全等具有一定的指导意义.

Hazard assessment of debris flows in Lanping County of Nujiang Prefecture based on key driving force

In recent years, there has been numerous outbreaks of lage-scale debris flow disaster in Nujiang Prefecture of Yunnan Province, which have caused heavy causalties and property losses.This paper takes debris flow of Lanping County, which boasts of rich mineral resources and hydropower, as the research object.By Site survey, combined with the existing research achievements, it scrutinizes the spatial distribution of debris flows in Lanping. After that, it builds hazard assessment index system of single debris flow based on key driving force, which consists of geographical, hydrodynamic and gravitational dimentions, using AHP and GIS technology to carry out risk evaluation.The research finds that among the 79 debris flows in the study area, there are 31 gullies at high risk and 32 in medium risk.Besides, The right and left banks of Lancang River are respectively concentrated with high and medium risk of debris flow gullies.Also, furthur analysis indicates that precipitation influences the occurrence of debris flow in Lanping.From the right bank of Lancang River to the left side and to Tongdian river, precipitation gradually decreases, so the risk of debris flows is reduced gradually at the same time.The findings of the research may be helpful to guide the construction of large-scale projects and secure its operation in Lanping County.