| Research Articles |
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| Aeolian transport over a developing transverse dune |
| ZhiBao DONG, Ping LV, ZhengCai ZHANG, JunFeng LU |
| Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China |
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Abstract The spatial and temporal changes in aeolian transport over a dune are fundamental factors that control the morphology of the dune. In the present study, we obtained direct field observations of aeolian transport over a developing transverse dune at the Shapotou Aeolian Experiment Site in the southeastern part of China's Tengger Desert. The transport rate versus wind speed relationship is complicated over a developing dune compared with the relationships over flat surfaces and over dunes that are in equilibrium with the wind. We obtained trend lines for transport rate over the transverse dune versus distance. The transport rate generally increased from the toe to the crest above the stoss slope, but the difference in transport rate between the crest and the toe was smaller than those that have been proposed for taller dunes. The crest/toe ratio for transport rates therefore seems to depend greatly on dune height. Flux density profiles for different points above the dune at different wind speeds were well described by the exponential decay law, as has been proposed for saltation flux density profiles. Coefficients in the flux density profile function can be defined in terms of the transport rate and wind speed. However, the dependence of relative decay rate with height and average saltation height on wind speed was weaker than that observed in a wind tunnel and above a flat surface. The preliminary results obtained in this study require more evidence from field observations to fully describe aeolian transport above developing dunes.
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Received: 17 April 2013
Published: 10 June 2014
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| Fund: The National Natural Science Foundation of China (41130533, 41171010). |
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Corresponding Authors:
ZhiBao DONG
E-mail: zbdong@lzb.ac.cn
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| Arens S M, van Kaam P, van Boxel J H. 1995. Airflow over foredunes and implications for sand transport. Earth Surface Processes and Landforms, 20: 315–332.Baas A C W, Sherman D J. 2005. Formation and behavior of aeolian streamers. Journal of Geophysical Research: Earth Surface, 110: F03011, doi: 10.1029/2004JF000270.Baddock M C, Wiggs G F S, Livingstone I. 2011. A field study of mean and turbulent flow characteristics upwind, over and downwind of barchan dunes. Earth Surface Processes and Landforms, 36: 1435–1448.Buffin-Bélanger T, Roy A G, Kirkbride A D. 2000. On large-scale flow structures in a gravel-bed river. Geomorphology, 32: 417–435.Burkinshaw I K, Rust I C. 1993. Aeolian dynamics on the windward slope of a reversing dune, Alexandria coastal dunefield, South Africa. Special Publication of the International Association of Sedimentologists, 16: 13–21.Butterfield G R. 1998. Transitional behavior of saltation: wind tunnel observations of unsteady winds. Journal of Arid Environments, 39: 377–394.Delgado-Fernandez I. 2011. Meso-scale modelling of aeolian sediment input to coastal dunes. Geomorphology, 130: 230–243.Dong Z, Liu X, Wang H, et al. 2003. The flux profile of a blowing sand cloud: a wind tunnel investigation. Geomorphology, 49: 219–230.Dong Z, Qian G, Luo W, et al. 2007. A wind tunnel simulation of the effects of stoss slope on the lee airflow pattern over a two-dimensional transverse dune. Journal of Geophysical Research-Earth Surface, 112: F03019, doi: 10.1029/ 2006JF000686.Dong Z, Lu J, Man D, et al. 2011. Equations for the near-surface mass flux density profile of wind-blown sediments. Earth Surface Processes and Landforms, 36: 1292–1299.Frank A, Kocurek G. 1996. Airflow up sand dunes: limitations of current understanding. Geomorphology, 17: 47–54.Fryberger S G. 1979. Dune forms and wind regime. In: Mckee E D. A Study of Global Sand Seas. Washington: U.S. Government Printing Office, 137–160.Fryrear D W. 1987. Aerosol measurements from 31 dust storms. In: Ariman T, Veziroglu T N. Particulate and Multiphase Flows: Contamination Analysis and Control. New York: Hemisphere Publishing Corp., 407–415.Hasi E, Dong G, Wang G. 1999. Morphodynamic study of reticulate dunes at southeastern fringe of the Tengger Desert. Science in China: Series D, 42: 208–215.Horikawa K, Shen H W. 1960. Sand movement by wind: on the characteristics of sand traps. Technical Memorandum. Washington, DC: Beach Erosion Board, U. S. Army Corps, 119.Hugenholtz C H, Wolfe S A, Walker I J, et al. 2009. Spatial and temporal patterns of aeolian sediment transport on an inland parabolic dune, Bigstick Sand Hills, Saskatchewan, Canada. Geomorphology, 105: 158–170.Lancaster N, Nickling W G, McKenna Neuman C, et al. 1996. Sediment flux and airflow on the stoss slope of a barchan dune. Geomorphology, 17: 55–62.Liu C. 1960. Transfer of sand in the surface layer. Acta Meteorologica Sinica, 31: 75–83.Livingstone I, Warren A. 1996. Aeolian Geomorphology: An Introduction. England: Addison Wesley Longman Limited, 211.Livingstone I. 2007. Geomorphology of desert dunes: a review of recent progress. Earth-Science Reviews, 80: 239–257.McKenna Neuman C, Lancaster N, Nickling W G. 2000. The effect of unsteady winds on sediment transport on the stoss slope of a transverse dune, Silver Peak, NV, USA. Sedimentology, 47: 211–226.Momiji H, Carretero-González R, Bishop S R. 2000. Simulation of the effect of wind speedup in the formation of transverse dune fields. Earth Surface Processes and Landforms, 25: 905–918.Nalpanis P. 1985. Saltating and suspended particles over flat and sloping surfaces: II. experiments and numerical simulations. In: Barndorff-Nielsen O E, Møller J T, Rasmussen K R, et al. Proceedings of International Workshop on the Physics of Blown Sand. Denmark: Aarhus University, 37–66.Nalpanis P, Hunt J C R, Barrett C F. 1993. Saltating particles over flat beds. Journal of Fluid Mechanics, 251: 661–685.Narteau C, Zhang D, Rozier O, et al. 2009. Setting the length and time scales of a cellular automaton dune model from the analysis of superimposed bed forms. Journal of Geophysical Research, 114: F03006, doi: 10.1029/2008JF001127.Ni J R, Li Z S, Mendoza C. 2002. Vertical profiles of aeolian sand mass flux. Geomorphology, 49: 205–218.Nickling W G. 1978. Eolian sediment transport during dust storms: Slims River Valley, Yukon Territory. Canadian Journal of Earth Science, 15: 1069–1084.Nordstrom K F, Jackson N L, Hartman J M, et al. 2007. Aeolian sediment transport on a human-altered foredune. Earth Surface Processes and Landforms, 32: 102–115.Parsons D R, Walker I J, Wiggs G F S. 2004. Numerical modelling of flow structures over idealized transverse aeolian dunes of varying geometry. Geomorphology, 59: 149–164.Pye K, Tsoar H. 1990. Aeolian Sand and Sand Dunes. London: Unwin Hyman Ltd., 396.Sauermann G, Andrade Jr J S, Maia L P, et al. 2003. Wind velocity and sand transport on a barchan dune. Geomorphology, 54: 245–255.Takeuchi M. 1980. Vertical profile and horizontal increase of drift-snow transport. Journal of Glaciology, 26: 492–498.van Boxel J H, Arens S M, van Dijk P M. 1999. Aeolian processes across transverse dunes. I: modelling the air flow. Earth Surface Processes and Landforms, 24: 255–270.van Dijk P M, Arens S M, van Boxel J H. 1999. Aeolian processes across transverse dunes. II: modelling the sediment transport and profile development. Earth Surface Processes and Landforms, 24: 319–333.Walker I J, Nickling W G. 2003. Simulation and measurement of surface shear stress over isolated and closely spaced transverse dunes in a wind tunnel. Earth Surface Processes and Landforms, 28: 1111–1124.Walker I J. 2005. Physical and logistical considerations of using ultrasonic anemometrys in aeolian sediment transport research. Geomorphology, 68: 57–76.Wiggs G F S. 1993. Desert dune dynamics and the evaluation of shear velocity: an integrated approach. In: Pye K. The Dynamics and Environmental Context of Aeolian Sedimentary System. Geological Society Special Publication, London: 72.Wiggs G F S, Livingstone I, Warren A. 1996. The role of streamline curvature in sand dune dynamics: evidence from field and wind tunnel measurements. Geomorphology, 17: 29–46.Wren D G, Kuhnle R A. 2008. Measurements of coupled fluid and sediment motion over mobile sand dunes in a laboratory flume. International Journal of Sediment Research, 23: 329–337.Zingg A W. 1953. Some characteristics of aeolian sand movement by saltation process. Édition du Center National de la Recherche Scientifique, 7: 197–208. |
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