Abiotic crust formation in fallow agricultural desert soils through carbonate cementation reduces fugitive dust

Abstract Unconsolidated soils typically develop a physical surface crust after wetting and drying. We reproduced this process in the laboratory by wetting with fog and simulated rain on fallow agricultural soils from 26 locations, representing 15 soil types from Pinal County, Arizona. Through correlative analyses, we found that carbonate content was a strong predictor of physical crust strength with fog ( p < 0.0001, R 2 = 0.48) and rain ( p = 0.004, R 2 = 0.30). Clay content increased crust strength ( p = 0.04) but was not a useful predictor. Our results extend the current understanding of the soil crusting process by highlighting the preeminence of carbonate cementation in desert agricultural soils. Consequently, we identify carbonate as a pragmatic tool for estimating crust strength, a surrogate measure of a soil’s potential to produce fugitive dust, which can help prioritize interventions to curb airborne dust in arid lands.