SOIL CARBON STOCK AND FERTILITY EVALUATION OF SELECTED LAND USE IN TOWNS OF AKOKO LAND, ONDO STATE, NIGERIA

Abstract

Land use plays an important role in the productivity and sustainability of soil. This study was carried out to determine the influence of land use on the availability of soil nutrient and top soil carbon stock in selected towns of Akoko Land. Soil samples were randomly collected at 0-30cm soil depth on three land use types (arable, oil palm and regrowth) at eleven locations (Akungba, Ayegunle, Iboropa, Ikare, Ipesi, Ise, Isua, Oba, Ogbagbi, Sosan and Supare) in Akoko land with the aid of hand trowel. The collected samples were analyzed for soil physical (bulk density, sand, silt and clay) and chemical properties (pH, OC, OM, N, P, K, Na, Ca, Mg, Al3+, EA, CEC and PBS). Data obtained from the analysis were subjected to statistical analysis of variance using Minitab version 17 and significant means (p ≤ 0.05) were separated using Tukey HSD test. Result obtained shows that soil physical properties and carbon pool do not differ significantly (P > 0.05) with land use type. There were significant differences (p ≤ 0.05) between arable land, oil-palm and re-growth soils for OC, N, K, Na and EA. There were significant differences (p ≤ 0.05) in the different locations in Akoko land for clay and silt content while no significant differences (p > 0.05) was observed for bulk density and sand content. Chemical properties of the soils in different locations in Akoko land only differ significantly (p ≤ 0.05) for phosphorus content. There was significant difference (p ≤ 0.05) in the different locations for carbon pool in the soil. There were no significant differences (p ≤ 0.05) in the physical properties of soils in Akoko land as affected by the interaction between location and soil condition except silt content. There were significant differences (P ≤ 0.05) between land use types (fallow > oil palm > arable) in various sites for soil pH, OC, N, P, K, Ca, Mg, EA, Al, CEC and PBS. The result also shows significant difference (p ≤ 0.05) in soil carbon pool across location.