Land Preparation Methods and Land Use and Their Effects on Soil Fertility in Relation to Cocoa Establishment in an Alfisol in Southwestern Nigeria

Abstract

This paper discusses problems of Land preparation methods and land use practices on soil fertility in relation to cocoa establishment and productivity.  Physical and chemical analysis of soils collected under different land preparation and land use practices (Bulldozed plot, slashed and burnt plot, un-cleared plot and arable land grown to cassava) were carried out in Ijeun Alagbede in Owode local government area of Ogun state to know their suitability or otherwise for cocoa production. The soil properties studied were soil texture, pH, total N, available P, exchangeable K, Ca, Mg, extractable Zn, Cu, Fe, Mn and organic carbon. Soil under bulldozed plot was very low in nitrogen compared to un-cleared and slashed and burnt plots.  Soils collected in the cassava plot had the lowest value of nitrogen. The most commonly observed change in soil following slash-and-burn clearing of tropical forest is a short-term increase in nutrient availability; hence cations were highest in slash and burnt plot. The soils had lower nitrogen and organic carbon compared to the critical values recommended for cocoa.