Aeolian Sand Transport Rate Over Windward and Lee Slopes of Small Reversing Dunes, Southern Morocco

  • Maciej DluzewskiEmail author
  • Joanna Rotnicka
Conference paper
Part of the Advances in Science, Technology & Innovation book series (ASTI)


Several factors affect the aeolian sand transport rate over reversing dunes. In arid zone poor in vegetation, the most important factors are effective wind direction in relation to the dune crest and the inclination of the windward slope. The objective of this paper is to analyze the variation in sand transport rate over such dunes under wind events differing in the direction of the incident wind including winds blowing from the direction of the former lee side. The research was carried out in the dune field of the Coude du Dra region (southern Morocco) where small reversing dunes, up to 3 m high, are numerous. In the case of wind blowing from the direction of low-angle slope, the sand transport rate increased tenfold between dune toe and crest when wind speed was well above the threshold value and around 25 times when wind speed was slightly greater than the threshold value. When the wind direction reversed and the steep lee slope became a windward slope, the sand transport rate at the dune crest was greater than in the previous case. It was caused by strong sand deflation that occurred at the dune crest due to its kinked profile.


Aeolian sand transport Reversing dunes Amplification factor 



The research has been supported by the National Science Center, Poland, project No. 2016/23/B/ST10/01700.


  1. 1.
    Hardisty, J., Whitehouse, R.J.S.: Evidence for a new sand transport process from experiments on Saharan dunes. Nature 332, 532–534 (1988)CrossRefGoogle Scholar
  2. 2.
    Zobeck, T.M.: Abrasion of crusted soil: influence of abrader flux and soil properties. Soil Sci. Soc. Am. J. 55(4), 1091–1097 (1991)CrossRefGoogle Scholar
  3. 3.
    Walker, I.J.: Secondary airflow and sediment transport in the lee of a reversing dune. Earth Surf. Proc. Land. 24, 437–448 (1999)CrossRefGoogle Scholar
  4. 4.
    Dong, Y., Hesp, P.A., Namikas, S.: Flow dynamics and sediment transport over a reversing barchan, Changli, China. Geomorphology 278, 121–127 (2017)CrossRefGoogle Scholar
  5. 5.
    Rotnicka, J.: Aeolian vertical mass flux profiles above dry and moist sandy beach surfaces. Geomorphology 187, 27–37 (2013)CrossRefGoogle Scholar
  6. 6.
    Cornish, V.: On the formation of sand dunes. Geogr. J. 9(3), 278–309 (1897)CrossRefGoogle Scholar
  7. 7.
    Parsons, D.R., Walker, I.J., Wiggs, G.F.S.: Numerical modelling of flow structure over idealized transverse aeolian dunes of varying geometry. Geomorphology 59, 149–164 (2004)CrossRefGoogle Scholar

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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Faculty of Geography and Regional StudiesUniversity of WarsawWarsawPoland
  2. 2.Institute of Geology, Adam Mickiewicz University in PoznańPoznańPoland

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