Abstract: [Purposes] To address the insufficient integration of multi-source data in rainfall-induced landslide early warning,this study developed an early warning system integrating 3D monitoring and multi-model analysis with Longyan city,Fujian province as the study area. [Methods] Based on 635 landslide events and corresponding rainfall data from 1984 to 2012,an EI-D rainfall threshold curve was established with a validation accuracy of 93%.A regional landslide susceptibility model was constructed using the FR-SVM method,yielding an AUC of 0.85.UAV photogrammetry and a six-camera array were employed for 3D slope reconstruction and deformation monitoring.FLAC3D fluid-mechanical coupling simulation revealed that the factor of safety decreased from 1.676 to 1.230 within five days of typhoon-induced rainfall,indicating that rainfall duration is a critical variable for slope instability. [Findings] The integrated early warning system achieves multi-level synergy from regional susceptibility assessment to individual slope deformation monitoring. [Conclusions] This paper provides technical reference for landslide prevention and control in similar rainfall-prone areas．

Key words: landslide warning system, susceptibility assessment, 3D monitoring, numerical simulation