Threshold Friction Velocities of Saltation Sand Particles for Different Soil Moisture Conditions in the Taklimakan Desert

Abstract

Using an objective method to calculate the saltation threshold friction velocity u_*t based on measurements using a sand particle counter, the values of u_*t were determined to be 0.48 and 0.56 m s^-1 under dry (θ_v = 0.002 m³ m^-3) and wet (θ_v = 0.009 m³ m^-3) conditions, respectively, at a gobi site in the Taklimakan Desert. This result shows that u_*t increased when soil moisture increased resulting from snowfall in March 2003. A simple relationship was found between the saltation flux q(z) at a reference height z and friction velocity u_* and u_*t.