A Wind Erosion Case Study in an Alpine Environment (Davos, Switzerland) Compared to Wind Tunnel Experiments with Live Plants

Frank Graf


It is generally accepted that the (re-)establishment of a protective vegetation cover is the most promising and efficient measure in restoring degraded land in the long term. Sustainable protection against wind erosion requires adequate information about suitable plant species regarding ecological aspects as well as with respect to their proper contribution to wind erosion control. The latter, however, is widely lacking. The goals of the presented field study are to record reliable data on windblown erosion rates under natural alpine conditions and to cross-link the findings with the results of wind tunnel experiments. A wind erosion test field was established at 2409 m a.s.l. in an alpine meadow including two test tracks. One track is left as is, representing the naturally alpine vegetated soil (10-20% plant cover). The other track is equipped with a plastic covering sheet, mimicking desertified soil (0% plant cover). Blue and red quartz sand was spread on the vegetated and sheet-covered track, respectively, to visualise and measure the effect of vegetation on wind erosion control. Compared to the bare soil it was found that only small amounts of sand from the vegetated plot were transported, even during heavy wind events. Related to the seasonal course, the overall ratio varied from 1:19 to 1:717. Qualitatively similar findings, however quantitatively less pronounced, resulted from the wind tunnel experiments (ratio = 1:15). Under consideration of all available information, the comparison with data from the field experiment considering only the configuration that best coincide with the wind tunnel set-up yields at least a 70-fold higher impact of plants on wind erosion control under natural conditions. The difference implies that the sheltering effect of vegetation in nature is much higher than found for wind tunnel runs, even when using live plants.


Land Degradation;

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Allgaier, A. (2008): Aeolian Sand Transport and Vegetation Cover. In: Breckle SW, Yair A, Veste, M (eds.) Arid Dune Ecosystems. Ecological Studies 200. Springer, Berlin Heidelberg, pp. 211-224.

Barabasi, A.L., Albert, R., Schier, P. (1999): The physics of sand castles: maximum angle of stability in wet and dry granular media. Physica A 266: 366-371.

Bauerle, T.L., Richards, J.H., Smart, D.R., Eissenstat, D.M. (2008): Importance of internal hydraulic redistribution for prolonging the lifespan of roots in dry soil. Plant, Cell and Environment 31: 177–186.

Burri, K., Gromke, C., Graf, F. (2011a): Mycorrhizal fungi protect the soil from wind erosion: a wind tunnel study. Land Degradation & Development, DOI: 10.1002/ldr.1136 (wileyonlinelibrary.com).

Burri, K., Gromke, C., Lehning, M., Graf, F. (2011b): Aeolian sediment transport over vegetation canopies: A wind tunnel study with live plants. Aeolian Research, 3: 205-213.

Degens, B.P., Spading, G.P., Abbott, L.K. (1996): Increasing the length of hyphae in a sandy soil increases the amount of water-stable aggregates. Applied Soil Ecology 3: 149-159.

Dong, Z., Sun, H., Zhao, A. (2004): WITSEG sampler: a segmented sand sampler for wind tunnel test. Geomorphology 59: 119-129.

Fujita, K., Ohta, T., Ageta, Y. (2007): Characteristics and sensitivities on climate change of runoff from a cold-type glacier on the Tibetan Plateau. Hydrol. Process, 21: 2882–2891.

Graf, F., Frei, M. (2013): Soil aggregate stability related to soil density, root length, and mycorrhiza using site-specific Alnus incana and Melanogaster variegatus s.l. Ecological Engineering 57: 314– 323.

Han, J., Nakawo, M., Goto-Azuma, K., Lu, C. (2006): Impact of fine-dust air burden on the mass balance of a high mountain glacier: a case study of the Chongce ice cap, west Kunlun Shan, China. Annals of Glaciology, 43: 23-28.

Hesse, P.P., Simpson, R.L. (2006): Variable vegetation cover and episodic sand movement on longitudinal desert sand dunes. Geomorphology 81, 276-291.

Lancaster, N., Baa, A. (1998) Influence of vegetation on sand transport by wind: Field studies at Owens Lake, California. Earth Surface Processes and Landforms 23: 69-82.

Li, J., Okin, G.S., Alvarez, L., Epstein, H. (2007): Quantitative effects of vegetation cover on wind erosion and soil nutrient loss in a desert grassland of southern New Mexico, USA. Biogeochemistry 85: 317-332.

Okin, G.S., Parsons, A.J., Wainwright, J., Herrick, J.E., Bestelmeyer, B.T., Peters, D.C., Fredrickson, L. (2009): Do changes in connectivity explain desertification? BioScience, 3: 237-244.

Querejeta, J.I., Egerton-Warburtona, L.M., Allen, M.F. (2008): Hydraulic lift may buffer rhizosphere hyphae against the negative effects of severe soil drying in a California Oak savanna. Soil Biology & Biochemistry 39: 409–417.

Rillig, M.C., Mummey, D.L. (2006): Mycorrhizas and soil structure. New Phytologist 171: 41-53.

Scheel, M., Seemann, R., Brinkmann, M., Di Michiel, M., Sheppard, A., Breidenbach, B., Herminghaus, S. (2008): Morphological clues to wet granular pile stability. Nature Materials 7: 189-192.

Sutter-Burri, K., Gromke C., Leonard, K.C., Graf, F. (2013): Spatial patterns of aeolian sediment deposition in vegetation canopies: Observations from wind tunnel experiments using colored sand. Aeolian Research 8: 65–73.

Wang, X., Shen, Y. (2009): Ecological restoration in West China: problems and proposals. Ambio, 38: 177-179.

Zobeck, T.M., Sterk, G., Funk, R., Rajot, J.L., Stou, J.E., Van Pelt, R.S. (2003): Measurement and data analysis methods for field-scale wind erosion studies and model validation. Earth Surf. Process. Landforms, 28: 1163-1188.