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The threshold friction velocities and soil flux rates of selected soils in south-west New South Wales, Australia

  • J. F. Leys
Part of the Acta Mechanica Supplementum book series (ACTA MECH.SUPP., volume 2)

Summary

A portable wind erosion tunnel has been used to measure the wind erodibility of nine soil types with a range of surface textures under two treatments (bare uncultivated and bare cultivated) in western New South Wales. The erodibility has been characterised by the soil flux function Q(u *), whereQis the streamwise soil flux (measured with a modified Bagnold soil trap) and u * the friction velocity (obtained by fitting the logarithmic wind profile law to a wind profile measured in the tunnel). Threshold friction velocities u *t were also observed for the range of surfaces. These data represent the only Australian tests published to date and supplement the American measurements of semi-arid soils by Gillette [1], [2], [3].

Averaging over 10 replicate plots for each surface type was necessary to smooth the large scatter in Q and smaller scatter in u *. The Q values spanned three decades of magnitude. Soils with a sandy loam surface texture were the boundary between the highly erodible sand and the basically noner-odible clay. Cultivation increased the erodibility of the majority of soils by about a factor of 10, but decreased the erodibility of the clay. The function Q(u * is well described by the Owen [4J soil flux equation. Threshold friction velocity decreased as soil texture became sandier. In comparison with work of Gillette [3], Australian soils have lower u *t values, which is most likely due to higher sand and lower silt contents.

Keywords

Wind Velocity Sandy Loam Surface Texture Friction Velocity Wind Erosion 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Wien 1991

Authors and Affiliations

  • J. F. Leys
    • 1
  1. 1.Soil Conservation Service of New South WalesBurongaAustralia

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