河西走廊泥石流灾害危险性评价及影响因子分析

发布时间：2018-03-22 00:29

  本文选题：泥石流灾害　切入点：危险性　出处：《自然灾害学报》2017年03期 　论文类型：期刊论文

【摘要】：河西走廊是丝绸之路经济带的黄金段和纽带,在国家"一带一路"战略中区位特殊,地位重要。以甘肃省地质灾害报告数据为基础,结合河西走廊地形地貌、水文、土壤和植被等情况,选取高程标准差、坡度、表层0~100 cm内的粘粒和砂粒含量、5-10月降雨量、河网密度和植被覆盖度等7个环境变量,利用Arc GIS技术建立了泥石流沟发育样点和环境变量空间分布图层,构建了河西走廊泥石流灾害危险性最大熵(Max Ent)分布模型,预测了河西走廊泥石流灾害危险性分布概率P,划分危险性等级,完成了河西走廊泥石流灾害危险性评价制图,并分析了各环境变量对P的贡献率和响应曲线。结果表明:P为0~0.95;其中,极高度危险区(0.5≤P≤0.95)面积约2.57万km~2,约占河西走廊总面积的9.92%;高度危险区(0.2≤P0.5)面积约4.11万km~2,约占河西走廊总面积的15.87%;中度危险区(0.09≤P0.2)约4.90万km~2,约占河西走廊总面积的18.92%;低度危险区(0≤P0.09)约14.32万km~2,约占河西走廊总面积的55.29%。
[Abstract]:The Hexi Corridor is the golden section and tie of the Silk Road economic belt. It has a special location and an important position in the national "Belt and Road" strategy. Based on the geological disaster report data of Gansu Province, and combined with the topography and geomorphology of the Hexi Corridor, the hydrology of Hexi Corridor, In soil and vegetation conditions, seven environmental variables, such as elevation standard deviation, slope, clay and sand content within 100 cm of surface layer and rainfall in May to October, river network density and vegetation coverage, were selected. Using Arc GIS technique, the spatial distribution layer of debris flow gully and environmental variables is established, and the maximum entropy Max Ent distribution model of debris flow hazard in Hexi Corridor is constructed. The probability of risk distribution of debris flow in Hexi Corridor is predicted, and the risk grade is classified, and the hazard assessment mapping of debris flow in Hexi Corridor is completed. The contribution rate and response curve of environmental variables to P were analyzed. Extremely high risk area 0. 5 鈮，

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