Abstract
Vegetation and other roughness elements distributed across a surface can providesignificant protection against wind erosion by extracting momentum from the flowand thereby reducing the shear stress acting at the surface. A theoretical model haspreviously been presented to specify the partition of drag forces for rough surfacesand to predict required vegetation density to suppress wind erosion. However, themodel parameters have not yet been constrained and the predictive capacity of themodel has remained uncertain. A wind-tunnel study was conducted to measure thedrag partition for a range of roughness densities and to parameterise the model inorder to improve its range of potential applicability. The drag forces acting on bothan array of roughness elements and the intervening surface were measured independentlyand simultaneously using new drag balance instrumentation. A detailed measure of thespatial heterogeneity of surface shear stresses was also made using Irwin sensors. Thedata agreed well with previous results and confirmed the general form of the model.Analysis of the drag partition confirmed the parameter definition β = CR/CS(where CR and CS are roughness element and surface drag coefficients,respectively) and a constant proportional difference between the mean and maximumsurface shear stress was found. The results of this experiment suggest that the definitionfor m, the surface shear stress inhomogeneity parameter, should be revised, although thetheoretical and physical reasons for including this parameter in the model appear to bevalid. Best-fit values for m ranged from 0.53 to 0.58.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Bradley, E. F.: 1968, 'A Shearing Stress Meter for Micrometeorological Studies', Quart. J. Roy. Meteorol. Soc. 94, 380–387.
Gillette, D. A. and Stockton, P. H.: 1989, 'The Effect of Nonerodible Particles on Wind Erosion of Erodible Surfaces', J. Geophys. Res. 94, 12885–12893.
Gillies, J. A.: 1994, A Wind Tunnel Study of the Relationship Between Complex Surface Roughness Form, Flow Geometry and Shearing Stress, Ph.D. Dissertation, University of Guelph, Canada, 231 pp.
Gillies, J. A., Lancaster, N., Nickling, W. G., and Crawley, D. M.: 2000, 'Field Determination of Drag Forces and Shear Stress Partitioning Effects for a Desert Shrub (Sarcobatus vermiculatus, Greasewood)', J. Geophys. Res. 105, 24871–24880.
Grant, P. F. and Nickling, W. G.: 1998, 'Direct Field Measurement of Wind Drag on Vegetation for Application to Windbreak Design and Modelling', Land Degrad. Dev. 9, 57–66.
Irwin, H. P. A. H.: 1980, 'A simple Omnidirectional Sensor for Wind-Tunnel Studies of Pedestrian Level Winds', J. Wind Eng. Ind. Aerodyn. 7, 219–239.
Iversen, J. D., Wang, W. P., Rasmussen, K. R., Mikkelson, H. E., and Leach, R. N.: 1991, 'Roughness Element Effect on Local and Universal Saltation Transport', Acta Mech. Suppl. 2, 65–75.
Kaimal, J. C. and Finnigan, J. J.: 1994, Atmospheric Boundary Layer Flows: Their Structure and Measurement, Oxford University Press, New York, 283 pp.
Kutzbach, J. E.: 1961, 'Investigation of the Modification of Wind Profiles by Artificially Controlled Surface Roughness', in Studies of Three-Dimensional Structure of the Planetary Boundary Layer, Annual Report Contract DA 36–039–SC-80282.Department of Meteorology, University of Wisconsin, Madison, WI, pp. 71–113.
Lancaster, N. and Baas, A.: 1998, 'Influence of Vegetation Cover on Sand Transport by Wind: Field Studies at Owens Lake, California', Earth Surf. Proc. Landforms 23, 69–82.
Lyles, L. and Allison, B. E.: 1976, 'Wind Erosion: The Protective Role of Simulated Standing Stubble', Trans. AMSE 19, 61–64.
Lyles, L., Schrandt, R. L., and Schmeidler, N. F.: 1974, 'How Aerodynamics Roughness Elements Control Sand Movement', Trans. AMSE 17, 134–139.
Marshall, J. K.: 1971, 'Drag Measurements in Roughness Arrays of Varying Density and Distribution', Agric. Meteorol. 8, 269–292.
McKenna Neuman, C.: 1998, 'Particle Transport and Adjustments of the Boundary Layer over Rough Surfaces with an Unrestricted, Upwind Supply of Sediment', Geomorphology 25, 1–17.
McKenna Neuman, C. and Nickling, W. G.: 1994, 'Momentum Extraction with Saltation: Implications for Experimental Evaluation of Wind Profile Parameters', Boundary-Layer Meteorol. 68, 35–50.
Monteiro, J. P. and Viegas, D. X.: 1996, 'On the Use of Irwin and PrestonWall Shear Stress Probes in Turbulent Incompressible Flows with Pressure Gradients', J. Wind Eng. Ind. Aerodyn. 64, 15–29.
Musick, H. B. and Gillette, D. A.: 1990, 'Field Evaluation of Relationships between a Vegetated Structural Parameter and Sheltering against Wind Erosion', Land Degrad. Rehabil. 2, 87–94.
Musick, H. B., Trujillo, S. M., and Truman, C. R.: 1996, 'Wind-Tunnel Modelling of the Influence of Vegetation Structure on Saltation Threshold', Earth Surf. Proc. Landforms 21, 589–605.
Nemoto, M. and Nishimura, K.: 2001, 'Direct Measurement of Shear Stress during Snow Saltation', Boundary-Layer Meteorol. 100, 149–170.
Nickling, W. G. and McKenna Neuman, C.: 1995, 'Development of Desert Lag Surfaces', Sedimentology 42, 403–414.
Nickling, W. G., Gillies, J. A., Lancaster, N., and Crawley, D. M.: 1999, Optimizing Managed Vegetation Planting Configurations at Owens Lake, California, Final Technical Report to Great Basin Unified Air pollution Control District, Bishop, CA, 76 pp.
Nielson, D. C. and Aiken, R. M.: 1998, 'Wind Speed above and within Sunflower Stalks Varying in Height and Population', J. Soil Water Cons. 53, 347–352.
Prandtl, L.: 1932, 'Zur turbulenten Strömung in Röhren und längs Platten', Ergebn. Aerdyn. Versuchsanst. 4, 18–29.
Raupach, M. R.: 1992, 'Drag and Drag Partition on Rough Surfaces', Boundary-Layer Meteorol. 60, 375–395.
Raupach, M. R., Gillette, D. A., and Leys, J. F.: 1993, 'The Effect of Roughness Elements on Wind Erosion Threshold', J. Geophys. Res. 98, 3023–3029.
Raupach, M. R., Thom, A. S., and Edwards, I.: 1980, 'AWind-Tunnel Study of Turbulent Flow Close to Regularly Arrayed Rough Surfaces', Boundary-Layer Meteorol. 18, 373–397.
Schlichting, H.: 1936,'Experimentelle Untersuchungen zum Rauhigkeitsproblem', Ingen.-Arch. 7, 1–34; NACA Tech. Mem. 823.
Siddoway, F. H., Chepil, W. S., and Armbrust, D. V.: 1965, 'Effect of Kind, Amount, and Placement of Residue on Wind Erosion Control', Trans. AMSE 8, 327–331.
Stacey, G. R., Belcher, R. E., and Wood, C. J.: 1994, 'Wind Flows and Forces in a Model Spruce Forest', Boundary-Layer Meteorol. 69, 311–334.
Stockton, P. H. and Gillette, D. A.: 1990, 'Field Measurement of the Sheltering Effect of Vegetation on Erodible Land Surfaces', Land Degrad. Rehabil. 2, 77–85.
Taylor, P. A.: 1988, 'Turbulent Wakes in the Atmospheric Boundary Layer', W. L. Steffen and O. T. Denmead (eds.), Flow and Transport in the Natural Environment: Advances and Applications, Springer-Verlag, Berlin, 270–292.
Thom, A. S.: 1971, 'Momentum Absorption by Vegetation', Quart. J. Roy. Meteorol. Soc. 97, 414–428.
Wolfe, S. A. and Nickling, W. G.: 1993, 'The Protective Role of Sparse Vegetation inWind Erosion', Prog. Phys. Geog. 17, 50–68.
Wolfe, S. A. and Nickling, W. G.: 1996, 'Shear Stress Partitioning in Sparsely Vegetated Desert Canopies', Earth Surf. Proc. Landforms 21, 607–619.
Wu, H. and Stathopoulos, T.: 1994, 'Further Experiments on Irwin's Surface Wind Sensor', J. Wind Eng. Ind. Aerodyn. 53, 441–452.
Wyatt, V. E. and Nickling, W. G.: 1997, 'Drag and Shear Stress Partitioning in Sparse Desert-Creosote Communities', Can. J. Earth Sci. 34, 1486–1498.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Crawley, D.M., Nickling, W.G. Drag Partition for Regularly-Arrayed Rough Surfaces. Boundary-Layer Meteorology 107, 445–468 (2003). https://doi.org/10.1023/A:1022119909546
Issue Date:
DOI: https://doi.org/10.1023/A:1022119909546