摘要:
滑坡作为黄河上游普遍存在的地质环境灾害现象,严重制约黄河流域生态保护和高质量发展。基于升、降轨时序合成孔径雷达干涉测量(Interferometric Synthetic Aperture Radar,InSAR)获取的地表形变速率和时间序列,开展黄河上游玛沁段的活动滑坡空间分布与军功巨型滑坡的时空演化特征分析。研究结果表明,黄河上游玛沁段发育活动滑坡124处,主要集中在黄河干流的两岸边坡,其聚集发育与黄河的长期下切和侵蚀作用密切相关。军功滑坡的三维形变揭示出该滑坡在空间上具有显著的不均匀形变特征,且水平向形变速率大于垂向。独立成分分析(Independent Component Analysis,ICA)进一步揭示了军功滑坡在不同区域表现出时空演化特征的差异性,表明了军功滑坡形变机理的复杂性。基于独立成分的层次聚类(Hierarchical Clustering,HC)将军功滑坡分为3个活动区域,分别反映了滑坡不同的演化规律和风险等级。本研究不仅为黄河上游滑坡灾害的管理和防治提供了科学依据,同时也为类似地质灾害的监测和分析提供了新的思路和方法。
Abstract:
Objectives: For a long time, landslides, as geological hazards, have been a significant factor influencing the ecological environment, landform evolution, and even the pattern of human settlement in the upper Yellow River basin. Studying the spatial distribution patterns and temporal evolution mechanisms of active landslides can help provide a scientific basis for the management and prevention of landslide hazards in the upper Yellow River. Simultaneously, it promotes the engineered application of radar remote sensing technology in landslide research, offering new ideas and methods for monitoring and analyzing similar geological hazards. Methods: First, based on 358 ascending and descending Sentinel-1 images spanning from January 2017 to July 2023, the small baseline subset interferometric synthetic aperture radar (SBAS-InSAR) technique was employed to obtain the surface deformation rates and time series in the study area. Subsequently, active landslides were interpreted and mapped by integrating InSAR velocities, optical imagery, and topographic data. Finally, a three-dimensional deformation model constrained by topographic factors was utilized to obtain the true deformation field of the Jungong landslide. Additionally, independent component analysis (ICA) and hierarchical clustering (HC) methods were introduced to investigate the spatio-temporal evolution characteristics of the Jungong landslide. Results: There are 124 active landslides developed in the Maqin section of the upper Yellow River, primarily concentrated on the slopes on both sides of the main stream, with more landslides occurring on the right bank than on the left. As a typical case, the Jungong landslide has undergone considerable surface deformation over the past few years, with horizontal movement being the dominant type of sliding. The surface deformation of the Jungong landslide exhibits spatially uneven distribution and significant variability in temporal evolution, which are related to the formation process and geological background of the landslide. Based on the distribution results of independent components, the landslides are clustered into three active zones, revealing different deformation patterns and risk levels. Conclusions: The concentrated occurrence of active landslides in the Maqin section of the upper Yellow River is related to the local landform changes caused by the long-term undercutting and erosion of the Yellow River. Specific areas of the Jungong landslide exhibit accelerated deformation, posing a risk of localized collapse, and thus require long term monitoring.