斜坡单元尺寸和滑坡取样方式对区域滑坡易发性评价的影响  

The impact of slope unit scale and landslide sampling methods on regional landslide susceptibility assessment

作　　者：杨仲康 张世殊 邓建辉[2] 李青春 纪海锋 赵思远 周小棚 YANG Zhongkang;ZHANG Shishu;DENG Jianhui;LI Qingchun;JI Haifeng;ZHAO Siyuan;ZHOU Xiaopeng(PowerChina Chengdu Engineering Corporation Limited,Chengdu,Sichuan 610031,China;College of Water Resources and Hydropower,Sichuan University,Chengdu,Sichuan 610000,China)

机构地区：[1]中国电建集团成都勘测设计研究院有限公司,四川成都610031 [2]四川大学水利水电学院,四川成都610000

出　　处：《岩石力学与工程学报》2025年第3期602-617,共16页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(U22A20601);西藏自治区科技重大专项课题(XZ202201ZD0003G);中国电力建设集团有限公司科技项目(P61124)。

摘　　要：近年来,斜坡单元自动提取技术取得了显著进展,但基于斜坡单元划分成果进行滑坡孕灾数据空间组织的研究仍显不足,尤其是斜坡单元尺寸和滑坡取样方式对区域滑坡易发性评价的影响尚不明确。以藏东南玉曲流域为研究对象,通过控制斜坡单元尺寸参数设置6种从精细到粗糙的评价单元尺寸,并基于滑坡矢量点和矢量多边形设计基于质心、基于相交质心和基于面积比阈值的3种滑坡取样方式,构建33组基于不同空间数据组织策略的滑坡-孕灾因子数据集,以进行滑坡易发性评价。研究结果表明,精细的斜坡单元尺寸难以获得较高的预测准确率,而粗糙的尺寸会导致易发性分区的合理性下降,尤其表现为区域滑坡易发性的过高估计。适中的斜坡单元尺寸能够提高模型的预测准确率,并实现更为科学合理的分区结果。该发现也验证了地形最大内部同质性与外部异质性原则在滑坡易发性评价中的有效性,进而为斜坡单元尺寸的适当选择提供了有力支持。此外,在复杂孕灾场景下,将滑坡质心所在的斜坡单元取样为滑坡标签是一种稳健合理的数据空间组织方式,有助于提升模型的预测准确率和分区表现。不同数据提取与分配策略下易发性评价结果的差异,主要源于滑坡与孕灾因子之间关联性的表达效果,尤其是滑坡与非滑坡场景信息能否被明确差异化和对立性呈现。该研究为藏东南高山峡谷地区基于斜坡单元的滑坡易发性建模与评价提供了有效参考,对复杂孕灾环境下滑坡风险评价结果的质量提升具有重要意义。Recent advancements in the automatic extraction of slope units have been significant.However,research on the effective organization of landslide hazard data based on slope units remains limited,particularly regarding the impact of slope unit scales and landslide sampling methods on regional landslide susceptibility assessments.This study focuses on the Yuqu River Basin in southeastern Tibet,where six slope unit scales,ranging from fine to coarse,were defined by adjusting slope unit size parameters.Additionally,three landslide sampling methodscentroid-based,intersecting centroid-based,and area ratio threshold-based—were developed using landslide vector points and polygons.These approaches enabled the construction of 33 distinct datasets for evaluating landslide susceptibility.The results indicate that fine-scale slope units struggle to achieve high predictive accuracy,while overly coarse units reduce the rationality of susceptibility zoning,particularly through the overestimation of highsusceptibility areas.A moderate slope unit size can enhance the model's predictive accuracy,leading to more reasonable partitioning results.This finding also validates the effectiveness of the principle of maximizing internal homogeneity and external heterogeneity of topography in landslide susceptibility assessments,providing robust support for the appropriate selection of slope unit sizes.Moreover,under complex environmental conditions,assigning the slope unit containing the landslide centroid as the sample proves to be a robust and rational method,enhancing both the predictive accuracy and zoning performance of the model.The variations in susceptibility assessment outcomes across different data organization strategies are primarily due to the effectiveness of the correlation between landslides and environmental factors,especially the distinctiveness between landslide and nonlandslide scenarios.This study provides a valuable reference for landslide susceptibility modeling based on slope units in the alpine canyon regions of sou

关 键 词：边坡工程 区域滑坡易发性评价 斜坡单元尺寸 滑坡取样方式 影响效应 形成原因 

分 类 号：P642[天文地球—工程地质学]