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

field study was conducted at five villages of Botswana namely, Tsabong, Tshane, Mathathane, Motlhabaneng and Tsetsejwe during the periods of June to August ۱۹۹۹ and June to August ۲۰۰۰. 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. 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کلیدواژه ها:

bulk density ، cultivation ، infiltration rate ، penetration resistance ، physicochemical properties ، soil degradation