A Simplified Model for Predicting Wind Erosion of Moistened Sands

Abstract

Wind erosion is responsible for the formation of various landforms and poses a significant risk to health, food security, and infrastructure. On Earth, the initiation of wind erosion is affected by the water content of the sediments, which can significantly increase the friction threshold velocity (FTV), which is the minimum wind velocity at the bed surface needed to initiate particle mobilization. Incorporating the effect of water on FTV is essential to assess problems such as sandstorm formation, topsoil removal in crops, or sand dune migration. In this study, a theoretical model is proposed to calculate the FTV in sands and horizontal surfaces using the principles of unsaturated soil mechanics. The sand matric suction is incorporated using soil water retention curves (SWRC). Two SWRCs are used resulting in simple functional forms that are easy to use. Data from the literature and new wind tunnel experiments are used to calibrate and validate the suggested FTV model. The results support the use of the proposed simplified equation as providing an adequate prediction of the FTVs of moistened sands.