Sediment dynamics in Africa are influenced by a complex combination of natural processes, environmental factors, and human activities. This study seeks to deepen our understanding of these dynamics by analyzing a comprehensive dataset. This dataset includes modelled Rill and Sheet Erosion (RSE), Landslide Mobilization Rates (LMR), Gully Head Susceptibility (GHS), and observed Sediment Yield (SY) from catchment outlets across Africa. The data is drawn from measurements of SY at 425 river outlets. Additionally, the study incorporates detailed maps and models for RSE, LMR, and GHS derived from high-resolution GIS data. In Africa, the mean observed SY is 6.07 t⋅ha-1⋅yr-1, while the mean RSE is 9.42 t⋅ha-1⋅yr-1, and the mean LMR is 1.51 t⋅ha-1⋅yr-1. Although gully erosion rates could not be directly quantified due to the lack of specific data, the GHS model indicates that gully erosion likely contributes significantly to overall SY, particularly in regions with high susceptibility. This is inferred from the significant correlation found between SY and GHS (r=0.57), suggesting that gullies are substantial sediment sources at the catchment scale. The weak correlation between SY and RSE suggests the need to include other sediment sources, like gullies and landslides, in sediment yield models. These findings highlight the importance of integrating multiple geomorphic processes to better assess sediment dynamics and guide land management strategies across different climate zones in Africa.

Sediment dynamics in Africa are influenced by a complex combination of natural processes, environmental factors, and human activities. This study seeks to deepen our understanding of these dynamics by analyzing a comprehensive dataset. This dataset includes modelled Rill and Sheet Erosion (RSE), Landslide Mobilization Rates (LMR), Gully Head Susceptibility (GHS), and observed Sediment Yield (SY) from catchment outlets across Africa. The data is drawn from measurements of SY at 425 river outlets. Additionally, the study incorporates detailed maps and models for RSE, LMR, and GHS derived from high-resolution GIS data. In Africa, the mean observed SY is 6.07 t⋅ha-1⋅yr-1, while the mean RSE is 9.42 t⋅ha-1⋅yr-1, and the mean LMR is 1.51 t⋅ha-1⋅yr-1. Although gully erosion rates could not be directly quantified due to the lack of specific data, the GHS model indicates that gully erosion likely contributes significantly to overall SY, particularly in regions with high susceptibility. This is inferred from the significant correlation found between SY and GHS (r=0.57), suggesting that gullies are substantial sediment sources at the catchment scale. The weak correlation between SY and RSE suggests the need to include other sediment sources, like gullies and landslides, in sediment yield models. These findings highlight the importance of integrating multiple geomorphic processes to better assess sediment dynamics and guide land management strategies across different climate zones in Africa.