Crop and management factor estimate for applying RUSLE in rangeland areas

The Revised Universal Soil Loss Equation (RUSLE) is a relatively simple model for estimating soil losses in agricultural lands and its use is attracting increasing attention around the world. Although all the factors in this model are receiving close attention and research is continuing to refine and improve the knowledge of how each factor affects erosion, much of research focus on the crop and management factor (C). Studies on the C-factor are continuing, not just for cropland where much of the research is occurring, but also for other agricultural land uses such as pasture, rangeland and forestland. In this paper, the results of a research involving 9 experimental plots located in Southern Italy aimed at validating some of the assumptions associated with the estimate of C-factor for rangeland conditions, are reported. The experiment involved rainfall, runoff and soil loss measurements for a three-year period which were used to evaluate the crop and management factor for perennial plants. Then, a simple procedure involving biomass seasonal measurements for evaluating the C-factor is proposed. The RUSLE model coupled with this empirical procedure showed good agreement between measured and calculated soil losses. Finally, in order to represent the model limitations and uncertainties, the effect of parameter uncertainty was studied by Monte Carlo method.