The Nutrient Status of Soils Under Peasant Cocoa Farms of Varying Ages in Southwestern Nigeria

Abstract

ABSTRACT The pattern of change of soil nutrient status under cocoa plantations, aged between one and 55 years, owned and managed by peasant farmers in southwestern Nigeria, was investigated. The mean values of the measured soil properties were significantly lower under cocoa than those under forest. The pattern of change of these properties over time under cocoa, however, demonstrated a small initial rise followed by a decline to about the tenth year. This was followed by an increase in their values reaching a peak about the twenty-fifth year. Consistent decreases in their values then followed. In order to maintain the nutrient status of the soil beyond the twenty- fifth year it would be necessary for farmers either to apply chemical fertilisers, or to use organic manure as a mulch in the practice of cocoa plantation management. It is also possible that appropriate agroforestry systems may be devised to achieve the same objective.