白龙江流域崩滑灾害孕灾因子聚类分区与道路工程扰动效应分析

CLUSTERING OF LANDSLIDE CAUSAL FACTORS AND ROAD ENGINEERING DISTURBANCE EFFECT ANALYSIS IN BAILONG RIVER BASIN

为探究白龙江流域内崩滑灾害的孕灾因子,以及道路工程活动对地质环境的扰动效应,本文通过野外考察和资料收集获取了2730个崩滑灾害点,使用GIS空间分析和遥感解译提取了地形地貌、地质构造、人类活动等方面的多个孕灾因子。基于信息量模型,分析了各因子的孕灾作用;采用空间约束多元聚类分析方法,依据各因子的特征和地理位置将崩滑灾害聚类,并利用随机森林算法获取了各类集群中各因子的重要性,分析了道路工程对崩滑灾害的扰动效应。结果表明,崩滑事件受海拔、坡度、坡向、降雨、岩性、断层、植被覆盖度、土地利用和道路工程扰动等多因子的共同作用。崩滑灾害可以被聚类为4个集群,不同集群区域内各孕灾因子对崩滑事件所起的重要性不同:多年平均降雨量对白龙江中游的A类集群重要性最高;海拔对白龙江上游的B类集群重要性最高;距断层距离对宕昌东北向的C类集群重要性最高;距公路距离对白龙江下游D类集群的重要性最高。道路工程的扰动效应表现为在地质环境脆弱的区域重要性较低,而在地质环境条件较好的区域重要性较高。

This paper aims to explore the causal factors and road engineering disturbance effect of landslides in the Bailong River Basin.We collected 2730 landslides through fieldwork and data collection.Several factors were extracted by GIS spatial analysis and remote sensing interpretation,including topography,geological structure,human activities,et al.The influence of factors on the landslides was analyzed based on the Information Value Model.We clustered landslides with the spatially constrained multivariate clustering method according to the geographic location and characteristics of factors.The importance of factors in clusters was obtained by the random forest algorithm.The disturbance effect of road engineering on landslides was analyzed.Results show that the landslides were affected by various factors including altitude,slope,aspect,rainfall,lithology,fault distance,vegetation coverage,land use,and road engineering disturbance.Landslides can be clustered into four clusters.The importance of factors that cause landslides is different among the clusters.“The multi-year average rainfall”is more important in Cluster A,located in the middle reaches of the Bailong River.“Elevation”is the most important for Cluster B,located in the upper reaches of the Bailong River.“The distance from the fault”is more important for Cluster C,located in the northeast direction of Tanchang.“The distance from the road”plays a more important role in Cluster D,located in the lower reaches of the Bailong River.The disturbance effect of road engineering is less important in areas with a fragile geological environment,but is more important in areas with better geological environment conditions.