Vegetation distributed a cross a surface provides significant protection against wind erosion in three ways. First, by extracting momentum form the wind flow reducing the shearing stress acting at the surface. Second, the vegetation shelters the surface from the erosive force of wind by covering a portion of the surface and finally, vegetation traps the soil particles in transport thereby acting as a catchment for sediment deposition, which was the core of this investigation.; This study was conducted to directly measure the rates of sand deposition and sand flux within a range of roughness concentration and element characteristics in order to determine the range surface cover needed to effectively reduce sand transport. A series of porous uniformly spaced arrays of non-erodible roughness elements were used in this investigation. The elements used in this investigation were constructed as clusters of dieldrin rods, vertically oriented forming porous non-erodible elements that were cylindrical in overall shape. In agreement with previous studies, sand deposition within the arrays was strongly related to the roughness concentration (lambda). Similarly, the rate of sand deposition was influenced by porosity such that a decrease in porosity led to reduced sand deposition. In this study, the Guelph Laser Profiling System was used to generate surface elevation contour maps. The generated maps demonstrated that the lee-side deposition with the elements varied with element concentration, roughness geometry and the wind speed, with most deposition occurring at lambda = 0.28 with uf of 10.4ms -1. A non-dimensional parameter Reff is introduced to quantify the effectiveness of the elements on the surface.
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