Purpose Land-use types influence near-surface soil characteristics, which in turn affects soil erodibility. However, limited studies have addressed the variation in soil erodibility near the Qilian Mountains. Existing assessments of soil erodibility largely rely on remote sensing, with limited in-situ data available.
Methods This study employed an in-situ soil sampling approach to investigate soil erodibility across five land-use types near the Qilian Mountains-grassland, shrubland, forest, sandy desert, and gravel desert. Soil erodibility was quantified using multiple indicators, including soil organic carbon (SOC), soil structural stability (SSI), clay ratio (CR), wind-erodible fraction of soil (EF), water erosion erodibility factor (K), and the comprehensive soil erodibility index (CSEI).
Results Soil particle size distribution showed a unimodal pattern, with fine particles (2-50 & micro;m) dominating grassland, shru-bland, and forest, and coarse particles (100-250 & micro;m) in deserts. Sand content increased with depth in grassland but decreased in shrubland and forest. SOC declined with depth and was lowest in sandy desert. Deserts had lower SSI but higher CR and EF, reflecting unstable aggregation. The K factor ranked: sandy desert> gravel desert> shrubland> forest> grassland. SOC and SSI mainly controlled CSEI in vegetated land, while CR and SSI dominated in deserts. Erosion resistance followed: grassland>forest> shrubland> sandy desert> gravel desert.
Conclusion These findings highlight vegetation-driven SOC-structure interactions as critical erosion buffers, advocating priori-tized conservation of vegetated ecosystems and adaptive management near the Qilian Mountains to mitigate soil degradation.
Highlights
In-situ sampling evaluates soil erodibility across five landscapes in the Qilian Mountains.
Sand content increased with depth in grassland but decreased in shrubland/forest.
Erosion resistance showed grassland > woodland > shrubland > sandy desert > gravel desert.
Vegetated landscapes stabilize soils via SOC and SSI, while deserts are erosion-prone due to high CR/EF.