African tropical wetlands such as the Okavango Delta located in semi arid regions are of great importance in sustaining the ecosystem. However little literature on soil nutrient dynamics of these areas is available. This paper presents preliminary results from 1997 of a continuing longterm study on the influence of the Okavango Delta annual inundation on soil nutrient status. In the study, soil K, Na, and pH between the different vegetation communities significantly increased (p <0.005) from the primary floodplain communities through secondary floodplains to island grasslands. Higher Ca was observed during the rains while higher Mg was observed after the rains. However, the influence of flood regimes on K, Na, available Ñ and pH within the community was non significant. Available P, Ca, and Mg between the different communities showed a significant decrease along an elevation gradient from the river bed. These results indicate that flooding has an influence on the soil nutrient content of the different communities depending on their distance and elevation gradient from the river bed. However, the influence of the flood regime within the individual vegetation community was usually non significant.
Bonyongo, M., Mubyana-John, T., Totolo, O., & M Veenandaal, E. (2002). Flooding and soil nutrient status in the Okavango Delta's seasonal floodplains. Botswana Notes and Records, 34. https://doi.org/10.2307/40980328