Evaluation of the CREAMS model. I. Sensitivity analysis of the soil erosion sedimentation component for aggregated clay soils

Abstract

The sensitivity of the soil erosion component of the CREAMS model to changes in various input parameters was assessed in the range of parameter values suited to erosion from aggregated clay soils. Predictions of total sediment yield were sensitive to changes in a number of parameters, and interactions between parameter values were observed, e.g., for situations when either detachment of sediment or transport capacity of overland flow limited sediment yield. The CREAMS model was classified as: (i) sensitive to: specific gravity of sediment (Sgi), slope steepness; (ii) sensitive under some conditions, moderately sensitive under others to: total runoff (Vu); Universal Soil Loss Equation factors of erodibility (K), cover (C) and support practices (P); Manning-type available shear parameter (nbov); (iii) moderately sensitive to: peak runoff rate (äp), storm erosivity (EI30), slope length, sediment size distribution and kinematic viscosity. The model was judged to be 'sensitive' to a parameter when change in that parameter caused an equal or greater relative change in predicted sediment yield.