Extending the RUSLE with the Monte Carlo error propagation technique to predict long term average off-site sediment accumulation

To evaluate if the adaptation of the basically two-dimensional Revised Univ ersal Soil Loss Equation (RUSLE) to a three-dimensional reality is appropri ate for predicting off-site sediment accumulation, it was. extended with th e Monte Carlo error propagation technique. This technique generates the tri te probability distribution of model output and gives the possibility to ex plain whether the difference between the model output and the field observa tions is largely due to the uncertainty of the model input or ir mainly due to the uncertainty, and limitations of the model itself. It was found that the RUSLE was able to accurately predict off-site sediment accumulation in the water reservoir of a study area. The value of the measured sediment in put was within the 68% confidence interval around the predicted value, with a difference of only 1.4%. Therefore, the error propagation explained this difference as mainly due to the uncertainty of the model input parameters. Consequently, it can be concluded that the topographic factor of the RUSLE model also can be considered ns a measure of the sediment transport capaci ty of the overland flow although it was originally developed for situations where detachment limits the sediment load.