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 (θv = 0.002 m3 m-3) and wet (θv = 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.