Vegetation Cover and Soil Erodibility Are More Strongly Associated with Wind Erosion than Climatic Erosivity in Arid Patagonian Rangelands

Abstract

Wind erosion is a major driver of land degradation in drylands worldwide, yet the relativeimportance of climatic forcing and local surface conditions remains poorly understood. Wequantified horizontal mass transport (HMT), characterized the particle-size distributionand organic matter of transported sediments, and identified the main environmentalcontrols on wind erosion across three rangeland sites in the Patagonian steppe of southernArgentina. HMT was monitored over one year using passive sediment collectors (Mende´zstrap), while climatic erosivity, vegetation cover, and topsoil properties were concurrentlyassessed. Wind erosion exhibited substantial spatial variability, with annual HMT rangingfrom 0.22 to 2.35 kg m−1 yr−1 among sites. Transported sediments were enriched in bothsilt and organic matter relative to source soils, indicating the preferential export of fine,carbon-rich fractions during aeolian transport. Multivariate analyses revealed that winderosion was more strongly associated with local vegetation cover and soil erodibility thanwith climatic erosivity. These findings suggest that surface conditions can override regionalclimatic controls on sediment transport in arid rangelands. Our results highlight the criticalrole of maintaining vegetation cover and soil surface stability to mitigate desertificationprocesses and provide empirical evidence to improve wind erosion assessment and landmanagement strategies in drylands.