Effects of Charcoal Production on Soil in Kiln Sites in Ibarapa Area, South Western Nigeria

Abstract

In Nigeria, charcoal is a major source of energy, especially among the urban poor. However, the effects of charcoal production on the environment, especially the soil, have not been adequately documented. This study examines the effects of charcoal production in kiln sites on soil properties in the derived savanna zone of Ibarapa region, south-western Nigeria. Soils in ten kiln sites were sampled at depths of 0-10cm and 10-20cm and their characteristics were compared with those of the corresponding layers of soil in ten adjoining derived savanna sites which were used as the control. Unlike in previous studies reported for West Africa, charcoal production in the kiln sites did not result in a significant reduction in soil organic matter levels, presumably because the humid climate of the derived savanna zone, hindered a substantial rise in soil temperatures during biomass burning. Similarly, there were no significant increases in the levels of exchangeable cations in both soil layers, except for soil exchangeable sodium. There was a rise in kiln site soil pH and available phosphorus mainly due to the effects of soil heating. Biomass burning in the kiln sites did not result in significant increases in the levels of the soil micronutrients - extractable iron, copper, zinc and manganese in both the 0-10cm and 10-20cm soil layers and it had no severe deleterious effects on soil chemical status.

Keywords: Charcoal production, kiln sites, macronutrients, micronutrients, Nigeria