Morphological characteristics and spatial distribution of shallow landslides in the Qinling-Daba Mountains, China

Shallow landslides dominate the hazard inventory of the Qinba Mountains, China, yet their regional-scale characteristics and controlling factors remain poorly understood. Based on 4,315 historical shallow landslides (1998–2022), this study integrates field measurements, GIS-based spatial analysis, and statistical methods to investigate landslide morphology, spatial distribution, and conditioning factors. Methodologically, we used variable-specific correlation analyses (Spearman, Cramér’s V , Kruskal–Wallis H tests) and multi-buffer processing for linear features (faults, rivers, roads). Results reveal: (1) Power law scaling in area-volume ( V = 2.27 A 1.034 ) and size-frequency distribution (exponent 2.27), confirming self-organized criticality of the landslide system. (2) Regional differentiation: the Hanjiang River basin shows a gradient from high-density, small failures upstream to lower-density, larger failures downstream; the Jialingjiang and the Hanjiang tributary basins are dominated by larger landslides due to competent lithologies and higher relief. (3) Key controlling factors: epimetamorphic rocks, elevation <1,000 m, slope <30°, relief <200 m, annual precipitation 800–1,100 mm, NDVI 0.5–0.7, population density >10 persons/km 2 , and distance to roads (<500 m), rivers (<1,800 m) and faults (<6,000 m). In general, macro-topography, regional tectonics, and climate collaboratively define the potential locations of landslides, whereas micro-topography, lithology, and vegetation cover govern their scale and type; Human activities change the dominant geometry of landslides to a certain extent. (4) The spatial pattern of landslide in continuous variables is analyzed at a 36 km distance threshold, with mean annual precipitation exhibiting the strongest positive spatial autocorrelation (Moran’s I = 0.93), and LISA maps show High-High clusters of precipitation and coefficient of elevation variation in Ankang, while elevation shows an opposite pattern. These findings provide a scientific basis for hazard mitigation and land-use planning in the Qinba Mountains and offer a methodological framework for landslide susceptibility studies in other geologically similar regions.