Unveiling coupled hydrological controls on landslide movement in the Longyangxia Reservoir area using multi-sensor satellite observations

The geological vulnerability of riverbanks has significantly intensified with the intensive construction of hydropower stations along rivers. Especially， wading landslides， owing to their dynamic driving forces， are prone to causing sudden disaster events. However， the dynamic deformation response of wading landslides to driving forces remains unclear. This study utilized Multi-Temporal Interferometric Synthetic Aperture Radar (MT-InSAR)， cluster analysis， and Seasonal-Trend decomposition using Loess to investigate the differential responses of various wading landslide types to hydrological drivers at Longyangxia Reservoir on the Tibetan Plateau. The findings reveal that different parts of reservoir landslides exhibit three deformation patterns in response to external triggers. Specifically， the deformation of the steady-type pattern is primarily governed by cumulative rainfall; that of the step-like pattern is jointly driven by water level changes and rainfall; and that of the oscillation-type pattern is mainly modulated by water level fluctuations. For riverside landslides， crown deformation is driven by the combined effects of rainfall infiltration and fluvial erosion， while toe deformation is mainly governed by fluvial erosion. Moreover， the integrated analysis of deformation velocity with Hurst index showed that reservoir landslides generally remain stable. This research can offer a scientific foundation for the safe operation of hydropower stations in reservoir areas.