Physicochemical Properties of Soil from Five Villages in Botswana with Respect to Soil Degradation

Abstract

field study was conducted at five villages of Botswana namely, Tsabong, Tshane, Mathathane, Motlhabaneng and Tsetsejwe during the periods of June to August 1999 and June to August 2000. The objective of the study was to assess and compare the soil physicochemical properties of soils at the five villages and to study the effect of cultivation on some soil physical properties. Parameters measured in the field included soil pH, organic carbon (OC), phosphorus (P), cation exchange capacity (CEC), exchangeable cations (Ca, Mg, K and Na), bulk density (BD), soil penetration resistance and infiltration rate. Soil pH, OC, CEC, Mg, Ca and BD were found to be significantly different in the five villages. The non-cultivated soil was found to have significantly lower bulk density, higher infiltration rate and higher penetration resistance compared to the cultivated soil. Soil from the Kgalagadi area was found to be significantly lower in nutrients in comparison with the soil from the Bobirwa area. The cultivated soil was found to have higher, bulk density, lower infiltration rate and lower penetration resistance.

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