摘要
信息量法是泥石流危险性评价的重要方法之一,本文以甘肃南部白龙江流域为研究区,根据地形、地貌、地质、环境等条件,选取高程、坡度、岩性、土地利用类型、滑坡点密度、地质构造缓冲区及归一化植被指数(NDVI)等7个评价因子,进行泥石流灾害危险性评价。文章基于GIS技术的空间分析功能及信息量法的定量分析功能,对各类因子进行分级计算与信息量赋值,生成各评价因子的信息量图层,并进行叠加分析,最终得到甘肃南部白龙江流域泥石流危险性分区图。结果表明,中度危险区以上的区域包含88.91%的泥石流。随着危险等级的增加,泥石流沟面积占危险等级面积比也随之增大。在中度危险区、高度危险区和极高度危险区内发生的泥石流面积分别占到各危险等级面积的21.21%、34.09%和46.00%,分析结果与实际灾害分布特征吻合较好。由此可见,信息量法与GIS技术结合对泥石流灾害进行危险性评价具有较高的准确性。
The Information Method is widely used in debris flow hazard assessment. In southern Gansu, the massive earthquake in Wenchuan provided a large amount of loose material and accelerated the occurrence of landsides and debris flow disasters. It is now necessary to investigate and analyze the factors that influence the debris flow in order to conduct a hazard assessment and prevention methods. Here, elevation, slope, lithology, land use, the density of landsides, cumulative distance from fault interface and normalized NDVI （normalized difference vegetation index） were selected for the Bailongjiang River as evaluation indexes for topography, geomorphology, geology and environmental conditions. We first classified influencing factors and then based on GIS and information methods generated evaluation factors information layers. The seven information layers were generated with Arcgis based on information values models and combined to arrive at a comprehensive information layer for debris flow hazards, and ultimately a debris flow hazard zoning map. The study area was divided into an extremely highly danger zone, high danger zone, moderate danger zone, mild danger zone and very mild danger zone. The results indicate that above moderate danger zone accounts for 88.9% of the total debris flow area;the moderate, high and extremely highly dangerous areas account for 29.48%, 34.33% and 25.10%, respectively. Our results show that information methods and GIS technology can be applied to debris flow disaster hazard assessment with higher accuracy and can contribute to disaster hazard prevention.
出处
《资源科学》
CSSCI
CSCD
北大核心
2013年第4期892-899,共8页
Resources Science
基金
国家科技支撑计划项目:"白龙江流域滑坡泥石流灾害多尺度风险评价与技术研究"(编号:2011BAK12B05)
关键词
泥石流
危险性评价
GIS
信息量法
白龙江流域
Debris flow
Hazard assessment
GIS
Information method
Bailong River Basin
作者简介
宁娜，女，甘肃武威人，硕士生，主要从事水文过程与泥石流灾害方面的研究。E—mail：ningn11@lzu．edu．cn
通讯作者：马金珠，E-majl：jzma@lzu．edu．cn
