Assessment of gully erosion process dynamics for water resources management in a semiarid catchment of Swaziland (Southern Africa)

In southern African countries, soil erosion and related problems like water quality issues or decreasing soil productivity are increasingly affecting the inhabitants of rural and urban areas. Problems related to soil erosion therefore have received increased attention in the recent past. Gully erosion processes especially play an important role for sediment production in many southern African catchments. Nevertheless, gully erosion phenomena have been widely neglected in erosion modelling. This study concerns the identification of spatially distributed erosion forms and processes in the Mbuluzi River catchment (Kingdom of Swaziland), with particular attention to gully erosion phenomena. The modelling of gully erosion was done successfully with models accounting for the two stages of development of a gully. The input data were obtained using remote sensing techniques and GIS-analyses. The example from Southern Africa shows that the methods applied are suitable for identifying and simulating the relevant erosional processes.