Soil erosion in the savanna biome national parks of South Africa

Abstract

Soil erosion has become a common feature in certain national parks across the global biomes, and national parks in the Savanna biome of South Africa have not been spared. Given their prominence in hosting large land mammals that contribute significantly to the tourism sector, the vulnerability of the parks to soil erosion merits attention. This study examines soil erosion status in the Savanna biome national parks of South Africa to recommend management practices aligned with the degree of erosion susceptibility. The results show that erosion rates across the national parks range between 0 and 25 t/ha/yr, and only a few have soil loss rates above 25 t/ha/yr. The Kgalagadi National Park has the lowest erosion rates, with a water erosion severity index (ESI) of 0. The Kruger and Mokala National Parks have low erosion rates, with an ESI of 0.017 and 0.01, respectively. The Mapungubwe National Park has moderate rates of soil loss, with an ESI of 0.023, while Marakele has the highest rates of soil erosion, with an ESI of 0.39. Soil erosion by water action is generally a minor environmental threat for the Kgalagadi, Kruger and Mokala National Parks. However, for Mapungubwe, soil erosion has a moderate threat, while in Marakele, it imposes a very high threat level. The different rates of soil erosion are attributed to the heterogeneous biophysical conditions of the Savanna biome, as well as different historical land use patterns across the parks. Climate change could be exacerbating the susceptibility of national parks to soil erosion. Park-specific management strategies that consider historical land use patterns and biophysical conditions within a climate change context are recommended.