Chaplot Vincent, Mutema M. (2022). Impact of overgrazing on diffuse and concentrated erosion : case study in the sloping lands of South Africa. Hydrology, 9 (7), p. 121 [9 p.].
Titre du document
Impact of overgrazing on diffuse and concentrated erosion : case study in the sloping lands of South Africa
Soil erosion is one of the most critical threats to cultivated land. Yet little information is available in Sub-Saharan Africa, especially on the relative contributions of various forms of erosion. Therefore, this study's objective was to quantify soil loss by sheet and linear erosion. The study was carried out on the sloping land rangeland of the Potshini catchment of KwaZulu-Natal, South Africa, with an annual average rainfall of 766 mm. The average sheet erosion computed using a network of 1 m(2) microplots was 7.7 ton ha(-1) y(-1) with standard error of 1.97 ton ha(-1) y(-1) (which corresponded to an ablation rate of between 0.35 to 1.32 mm y(-1)) while linear erosion, mainly the retreat of gully banks, removed 4.8 ton ha(-1) y(-1), i.e., 38.4% of total soil losses. Despite removing a lower amount of soil, sheet erosion by depleting fertile, carbon- and nutrient-enriched soil horizons has a great impact on most ecological functions associated with soils.
