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为定量探究区域滑坡空间分布结构,揭示不同规模类型区域滑坡分布模式异同,分析其异同原因,拓深对区域滑坡空间分布规律的认知,在建立黄土滑坡详细编录数据库的基础上,借鉴粒度分析理论,引入滑坡径级概念。采用关联维数、核密度和GIS空间分析方法,定量地分析不同径级上区域黄土滑坡空间分布结构及其形成原因。结果表明:(1)径级50~75 m黄土滑坡所占比例最大,占到滑坡总数的28.87%;径级>100 m黄土滑坡所占比例较小,占到滑坡总数的15.12%;(2)各径级区域滑坡空间结构具有多分形特征,在30 km尺度上存在明显的拐点;在小于30 km尺度上区域滑坡各径级的关联维数随着径级规模增大而增加,分布模式由聚集分布逐渐过渡到分散分布,在大于30 km尺度上区域滑坡都呈现聚集分布状态;(3)成因分析表明,黄土滑坡在发育过程中,更多是受地形地貌的影响,在遴选的3个分布模式主要影响因素中,距河流距离对区域黄土滑坡分布模式的影响最大,其次为地形起伏度,小规模滑坡在距河流距离近(地形起伏度小)的地方所占比例较高,而大规模滑坡在距河流距离远(地形起伏度大)的地方所占比例较高。坡度虽然是影响滑坡稳定性的重要影响因子,但对于分布模式的影响几乎没有。
In order to quantitatively study the spatial distribution structure of landslides and to reveal the similarities and differences of landslide distribution patterns in different types of scales, the similarities and differences of the landslides are analyzed and the cognition of spatial distribution of landslides is explored. Based on the detailed catalog database of loess landslides, Theory, the introduction of landslide diameter concept. The correlation dimension, nuclear density and GIS spatial analysis method were used to quantitatively analyze the spatial distribution of loess landslides in different diameter classes and their causes. The results show that: (1) Loess landslide with the diameter of 50 ~ 75 m occupies the largest proportion, accounting for 28.87% of the total number of landslides; Loess landslides with the diameter of> 100 m account for a small proportion, accounting for 15.12% of the total; The spatial structure of the landslides in each diameter class has the characteristic of multifractal, and there is a significant inflection point on the scale of 30 km. The correlation dimension of each grade of landslides increases with the increase of diameter class on the scale of less than 30 km. (3) The genetic analysis shows that the loess landslide is more affected by the topography in the development process. In the selected 3 Among the main influencing factors, the distance from the river has the greatest influence on the distribution pattern of loess landslides in the region, followed by the undulating degree of the terrain. The small-scale landslide has a higher proportion of places near the river (less relief), while Large-scale landslides are at a high percentage of places far from the river (with high relief). Although the slope is an important factor affecting the stability of landslide, it has almost no effect on the distribution pattern.