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_ revegetated sites and the adjacent undisturbed area through the use of the Universal Soil <br />Loss Equation (USLE) (Wishmeier and Smith, 1965, Hamon, 1982). <br />• <br />The USLE uses readily available information on the rainfall, topography, soil particle <br />size characteristics, vegetation, and cultivation practices to generate the amount of soil <br />loss from -a specific area in tons /acre /year. The USLE accounts for rill and inter -rill <br />erosion, the types of erosion commonly found on reclaimed areas. <br />The USLE takes the form: <br />A= R *K *LS *C *P <br />where: <br />A = soil loss in tons /acre /year <br />R = rainfall factor accounting for the interrelationship between the erosive <br />force of rainfall and runoff, based on amount, time, and intensity <br />K = soil erodibility factor addressing a given soil's susceptibility to erosion <br />LS = length slope factor providing the ratio of soil loss at any length and slope <br />to a standard slope and length <br />C = cropping- management factors are the ratios of soil loss from lands cropped <br />under specific conditions to known losses from tilled continuous fallow <br />lands <br />P = erosion control practice factor is the ratio of soil loss with a specific <br />support practice to the corresponding loss with up /down slope culture <br />Each of the above factors will be briefly addressed relative to the existing conditions at <br />each of the reclaimed or revegetated areas and the adjacent undisturbed vegetation <br />community. <br />RAINFALL FACTOR (R) <br />The rainfall factor addresses the interrelationship of the erosive forces of falling <br />raindrops and runoff to predict both rill and inter -rill erosion. Hamon (1982) has <br />assigned rainfall factor values for the State of Colorado based on U.S. Weather Service <br />data. R factors for the reclaimed and revegetated areas and the adjacent undisturbed <br />areas are drawn from Hamon (1982). These factors are the same for each reclaimed, <br />revegetated, or undisturbed area, as there is not a significant difference between the <br />rainfall falling on the 'declaimed or revegetated areas and adjacent undisturbed <br />vegetation. G; <br />In this demonstration, a value of 40 was selected for the runoff and rainfall factor R. <br />• <br />I <br />-2- <br />