Abrasion of crusted soils: influence of abrader flux and soil properties
1991
Zobeck, T.M.
Surface crusts greatly affect soil susceptibility to wind erosion. Little is known about the effects of soil properties and environmental factors on crust abrasion. In this study, the influence of abrader flux, degree of crust consolidation, and selected soil properties on soilcrust erosion was evaluated and statistically modeled. Fourteen soils, representing a wide range of physical and chemical properties, were evaluated. Soils were subjected to simulated rainfall rates of either 25 or 64 mm h-1, air dried, and abraded at mass fluxes of 0.010, 0.025, and 0.050 kg m-1 s-1. Crust abrasion (abrasion coefficient, AC) was defined as the slope of the linear regression of cumulative soil loss vs. cumulative abrader passage. An analysis of variance indicated that abrader flux, crust consolidation level soil properties, and their interactions significantly affected (P < 0.05) soil loss. The AC ranged from 3.179 m-1 for an organic soil to 0.002 m-1 for silt loam and clay soils. The range of AC for unconsolidated soils was from 5 to 5000 times greater than for crusted soils. The mean AC for unconsolidated soils was 40 and 70 times greater than for crusted soils created at rainfall rates of 25 and 64 mm h-1, respectively. Regression analyses revealed that the natural logarithm of AC was positively correlated with sand content and the cation-exchange capacity/clay ratio, and negatively correlated with abrader flux.
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