摘要
选取白龙流域内具有代表性的清水沟小流域,以清水沟承灾体个体为评价单元,基于遥感数据和广义目标函数方法,引入地质灾害直接威胁概率指标,构建了小流域地质灾害易损性评价指标体系和评价方法,开展了清水沟大比例尺易损性评价.结果显示:清水沟小流域易损性为0～0.105的低易损性承灾体面积占全流域面积的88.4%,0.106～0.251的中易损性承灾体面积占10.2%,0.252～0.812的高易损性承灾体面积仅占1.4%.从空间分布上看,低易损性承灾体主要分布在中上游,以草地、林地和耕地为主,高易损性承灾体主要分布在下游,特别是沟口冲积扇上的居民区,以房屋、公路、桥梁为主.流域内滑坡体对于其下方的沟道以及下游的居民区有较大威胁,导致这些区域的易损性显著增加.应当做好对滑坡体的防护措施,并对下游的居民区进行重点保护.
Qingshui, a typical and representative small watershed in Bailongjiang Basin, where severely harm-ful geo-hazards occurred frequently, was selected as the study area, then a large-scale geo-hazard vulnerability assessment system and methods for small watershed were constructed and, furthermore, a high resolution vulner-ability assessment of Qingshui Watershed by the generalized objective function method was made based on RS data. The results showed that, in the small Qingshui Watershed, the low vulnerability area with value between 0 to 0.105 accounts for 88.4%of the whole watershed. The area with vulnerability value between 0.106 to 0.251 accounts for 10.2%. And the high vulnerability area between 0.252 to 0.812 accounts for only 1.4%. As for the spatial distribution, the low vulnerability areas are mainly located in the upper reaches where grassland, forest land and farmland spread over, while the high vulnerability areas are mainly distributed in the downstream, especially the residential areas near the outlet where houses, roads, bridges are concentrated. In addition, the hazard-bearing bodies where landslide mass lie are mainly grassland at a low price, so their vulnerability values are not high, but landslides pose a great threat to the channels and residential areas downstream. Therefore controls should be administered to the landslides, to prevent dangers for the residential areas downstream.
出处
《兰州大学学报（自然科学版）》
CAS
CSCD
北大核心
2014年第5期671-675,共5页
Journal of Lanzhou University(Natural Sciences)
基金
国家科技支撑计划项目(2011BAK12B05
2011BAK12B06)
甘肃省科技重大专项计划项目(1102FKDA007)
国家国际科技合作计划项目(2013DFE23030)
关键词
易损性
地质灾害
承灾体
广义目标函数
清水沟
vulnerability
geo-hazard
hazard-bearing body
generalized objective function
Qingshui Watershed
