Evaluating soil erodibility dynamics to improve estimates of wind erosion in drylands

Title Evaluating soil erodibility dynamics to improve estimates of wind erosion in drylands
Publication TypeConference Paper
Year of Publication2015
AuthorsGalloza M, Webb N, Zobeck TM, Herrick JE
Conference Name18th International Soil Conservation Organization Conference
Date Published05/2015
Conference LocationEl Paso, Texas
ARIS Log Number318565

Wind erosion is a key driver of land degradation in the world’s drylands. Soil loss and nutrient decline due to wind erosion increase the sensitivity of drylands to climate stressors. Better understanding the factors controlling wind erosion in drylands will provide a basis for identifying and testing best management practice options. Much remains unknown about the role of dynamic soil surface properties, such as erodible sediment supply and soil crusting, in controlling rates of wind erosion. This research evaluates the role of changing soil surface conditions in controlling the susceptibility of soils to wind erosion. The objectives of this study were to: (1) determine the entrainment threshold for five different undisturbed dryland soils; (2) evaluate the magnitude of horizontal mass flux and its relation to the entrainment threshold at the studied sites; and (3) to identify the impact of annual seasons when evaluating the temporal variability in entrainment threshold and horizontal mass flux. Although large differences in sediment flux were present among sites, only minimal differences in threshold wind speed were found among them, despite large differences in soil surface conditions. The results suggest that sediment transport was influenced strongly by the availability of loose erodible sediment and soil abrasion processes during transport. Inclusion of these factors in wind erosion models may reduce model uncertainty, enabling more accurate assessments of wind erosion under different land use and land management scenarios.