Work

Global satellite analysis reveals landslide susceptibility peaks at intermediate vegetation density

Year: 2026

Type: article

Abstract: Landslide hazard models worldwide assume that vegetation stabilizes slopes monotonically, so that denser vegetation always implies greater stability. Analyzing 12,459 rainfall-triggered landslides (2000–2024) with multi-source satellite data, we find a "vegetation paradox": landslide susceptibility does not decline monotonically with vegetation density but peaks within a critical transition zone (CTZ) at NDVI, 0.769–0.868—a unimodal, non-monotonic pattern. This zone concentrates 23.0% of the full 18,028-event inventory (33.2% of the 12,459 analyzed with reliable NDVI) and persists across biomes, climate zones, and slope classes (16.7%–44.5% CTZ prevalence across the gentle-to-steep range), and its upper boundary is stable across data-quality filtering, density smoothing, and simulated sensor noise. An independent grid-based Random Forest ( R 2 = 0.446) independently places this maximum within the CTZ (mean NDVI, 0.860) without histogram binning; its coarse grid, however, captures only the rising limb and cannot resolve the decline above the CTZ.

Source: iScience

DOI: 10.1016/j.isci.2026.117271