近日，中国科学院山地灾害与环境研究所Runing Hou团队报道了没有强降雨的滑坡是如何发生的：早期强径流与弱岩土材料相吻合。该研究于2026年4月13日发表在《地质学》杂志上。

强降雨被广泛认为是滑坡的主要触发因素，并常用于早期预警系统。然而，许多意外失稳事件却发生在少雨甚至无雨时期，导致预警失效、疏散失败。无强降雨条件下滑坡发生的机制仍未得到探索。

通过整合实地调查、机器学习、遥感与数值模拟，研究组发现无强降雨条件下的滑坡灾害广泛存在：在1118起灾难性滑坡案例中，75.7%表现出延迟发生特征，其受控于前期降雨、地形湿度指数以及滑坡规模。研究组首次识别出三种径流补给模式（斜坡补给、沟谷补给和溪流补给）以及两个运移阶段（地表和地下），这些因素共同控制了汇水区强烈的径流补给。

该工作提出了一个创新视角，即早期强径流与软弱岩土体的耦合作用会触发延迟型失稳，并揭示了三个地下径流阶段——壤中流、滑面流和回流。这些结果阐明了延迟型滑坡背后的水文-岩土耦合机制，有助于改进早期预警和预测，从而降低风险。

附：英文原文

Title: How landslides happen without heavy rainfall: Early strong runoff coincides with weak geomaterials

Author: Shufeng Tian, Kanglin Wu, Ningsheng Chen, Alessandro Simoni, Yongjian Li, Haixu Liu, Jiming Jin, Tao Wen, Taixin Peng, Runing Hou

Issue&Volume: 2026-04-13

Abstract: Intense rainfall is widely recognized as the primary trigger for landslides and is commonly used in early warning systems. Yet, many unexpected failures occur during periods of little or even no rainfall, leading to ineffective warnings and failed evacuations. The mechanisms by which landslides occur without heavy rainfall remain unexplored. Integrating field investigations, machine learning, remote sensing, and numerical simulations, we found that landslide disasters without heavy rainfall are widespread: 75.7% of 1118 catastrophic cases exhibited delayed onset, controlled by antecedent rainfall, the topographic wetness index, and landslide scale. For the first time, we identified three runoff-supply patterns (slope, gully, and creek supply) and two migration stages (surface and subsurface) that together govern strong runoff supply in confluence zones. Our work contributes an innovative perspective on the coupling of early strong runoff and weak geomaterials that triggers delayed failures, with three subsurface runoff stages—interflow, sliding-face flow, and return flow. These results clarify the hydro-geomaterial coupling behind delayed landslides and support improved early warning and prediction to reduce risk.

DOI: 10.1130/G54187.1

Source: https://pubs.geoscienceworld.org/gsa/geology/article-abstract/doi/10.1130/G54187.1/728382/How-landslides-happen-without-heavy-rainfall-EarlyredirectedFrom=fulltext