Landslides along the Engineering Corridors in the Northeastern Margin of the Qinghai-Tibet Plateau: Comprehensive Inventory and Distribution Patterns

The Engineering Corridors (ECs) in the northeastern margin of the Qinghai-Tibet Plateau (NE-QTP) include sections of highways, railways, and pipelines that are constructed on permafrost terrain, seasonally frozen ground, and loess. Climate change, earthquakes, and human disturbance are accelerating the degradation of permafrost, causing loess failures, and developing slope instability that are leading to numerous freeze-thaw landslides (FTLs), loess landslides (LLs), and general landslides (GLs). These events often result in road cracks and infrastructure damage. However, few systematic investigations have been carried out in this area. To compile a comprehensive landslide inventory, this study utilizes visual interpretation to identify landslides in Gaofen-6 images (2 m) taken between 2021 and 2022, covering an area of 30×104 km2. Then, field investigations were conducted to validate and evaluate the inventory accuracy. We identified 11,914 landslides, including 1,095 FTLs, 7,930 LLs, and 2,889 GLs, while 10,825 of the landslides occurred within a 20 km range of the ECs. More specifically, FTLs are distributed in the boundary regions between permafrost and seasonal frozen ground. LLs and GLs have a dense cluster distribution along rivers. In addition, landslides are prone to develop on north-facing slopes, with steep slopes for LLs and GLs and gentle slopes for FTLs. Moreover, LLs and GLs occurred mainly at lower-medium elevations (1500-3000 m), while FTLs developed at higher elevations (3000-4000 m). Landslides primarily occur in regions that are covered with meadows, shrublands, and agricultural vegetation. Our inventory is helpful for in-depth research on landslides in the NE-QTP. It will also provide a significant and valuable dataset for quantifying the analysis of landslides along the ECs that are experiencing climate changes, strong earthquakes, and extensive human activities.