A Wind Erosion Equation

Abstract

The amount of erosion, E, expressed in tons per acre per annum, that will occur from a given agricultural field can be expressed in terms of equivalent variables as: E = f(I′, K′, C′, L′, V) where I′ is a soil erodibility index, K′ is a soil ridge rougness factor, C′ is a climatic factor, L′ is field length along the prevailing wind erosion direction, and V is equivalent quantity of vegetative cover. The 5 equivalent variables are obtained by grouping some and converting others of the 11 primary variables now known to govern wind erodibility. Relations among variables are extremely complex. Charts and tables have been developed to permit graphical solutions of the equation. The equation is designed to serve the twofold purpose of providing a tool to (i) determine the potential erosion from a particular field, and (ii) determine what field conditions of soil cloddiness, roughness, vegetative cover, sheltering by barriers, or width and orientation of field are necessary to reduce potential erosion to a tolerable amount. Examples of these applications of the equation are presented. Weaknesses in the equation and areas needing further research are discussed.

Measurement and data analysis methods for field‐scale wind erosion studies and model validation

“…SENSIT particle impact sensor (adapted from Stout and Zobeck (1997) Lopez et al, 1998Sterk et al, 1999Gomes et al, 2003aGomes et al, 2003bStetler et al, 1994Stetler and Saxton, 1996Stout and Zobeck, 1996 1965;Soil Survey Staff, 1988Fryrear et al, 1998Potter et al, 1998Hagen, 1991Gregory and Darwish, 2001Marticorena and Bergametti, 1995Alfaro and Gomes, 2001Shao et al, 1996Stout, 1990Gillette et al, 1996). The rate at which mass transport increases with distance is a function of field characteristics.…”

“…Oriented roughness can be described by measuring tillage ridge height and spacing. The ridge-to-height ratio is used in the Wind Erosion Equation (WEQ) (Woodruff and Siddoway, 1965).…”

The measurement of wind erosion through field survey and remote sensing: a case study of the Mu Us Desert, China

“…Many factors have been studied that can affect wind erosion, primarily related to wind speed, soil moisture, soil texture, vegetation cover, and human activity (Woodruff and Siddoway 1965;Hagen 1991;Hagen et al 1995;Dong et al 1996;Fryrear et al 1998;Shao et al 1996;Lu and Shao 2001;Gregory et al 2004;Coen et al 2004). However, the models used in these studies do not necessarily perform better than our model, which might be explained by the fact that the relationship between wind erosion with the model variables remains unclear or is very hard to determine (Woodruff and Siddoway 1965;Dong 1998). For this reason, collecting sufficient empirical data of adequate quality and finding the most sensitive factor may be more helpful than using multiple factors to build a regional wind erosion model (Stroosnijder 2005).…”

Development of a PM2 5 Emissions Inventory for the South Coast Air Basin

“…The method recommended by the EPA 5 involves a vertical dust flux equation that requires many parameters that are difficult to obtain. A second approach recommended by the CARB, and the one adopted by the SCAQMD, involves the use of the wind erosion equation developed by the U.S. Department of Agriculture (USDA) 13 to estimate total soil loss and then assignment of a fraction of the loss as PM 10 . The USDA wind erosion equation is written as follows:…”