Regionalising MUSLE factors for application to a data-scarce catchment

• Main Authors: D. Gwapedza, A. Slaughter, D. Hughes, S. Mantel
• Format: Article
• Language: English
• Published: Copernicus Publications 2018-04-01
• Series: Proceedings of the International Association of Hydrological Sciences
• Online Access: https://www.proc-iahs.net/377/19/2018/piahs-377-19-2018.pdf

The estimation of soil loss and sediment transport is important for effective management of catchments. A model for semi-arid catchments in southern Africa has been developed; however, simplification of the model parameters and further testing are required. Soil loss is calculated through the Modified Universal Soil Loss Equation (MUSLE). The aims of the current study were to: (1) regionalise the MUSLE erodibility factors and; (2) perform a sensitivity analysis and validate the soil loss outputs against independently-estimated measures. The regionalisation was developed using Geographic Information Systems (GIS) coverages. The model was applied to a high erosion semi-arid region in the Eastern Cape, South Africa. Sensitivity analysis indicated model outputs to be more sensitive to the vegetation cover factor. The simulated soil loss estimates of 40 t ha⁻¹ yr⁻¹ were within the range of estimates by previous studies. The outcome of the present research is a framework for parameter estimation for the MUSLE through regionalisation. This is part of the ongoing development of a model which can estimate soil loss and sediment delivery at broad spatial and temporal scales.