High levels of micronutrients may cause metabolic disorders and become growth inhibitors to most plant species. Therefore, the study assessed the levels of micronutrients in soils under oil palm cultivation in a coastal plain sands area of Akwa Ibom State, Nigeria. Three oil palm blocks of varying ages, l7 years (B-17), 39 years (B-39) and 57 years (B-57) and no oil palm block (B-O), which served as the control, were identified and selected for the study in the Nigeria Institute for Oil palm Research (NIFOR) sub-station, Ibesit Ekoi, Oruk Anam Local Government area of Akwa Ibom State. Three profile pits were sunk in each location, and soil samples were collected and subjected to laboratory and statistical analysis. The results showed that zinc had the highest level in the study area soils while copper had the lowest level among the micronutrients tested. All the micronutrients tested were within the permissible range for agricultural soils. Copper, Mn, Zn, and Fe contents of the soil in B-17 were significantly higher than in the other blocks. The trend of Cu and Mn was as follows: B-17 B-57 control B39, while that of Zn and Fe was as follows, B-17 B-57 B-39 control. Oil palm increased the soil Cu, Mn, Zn and Fe levels. This shows that oil palm positively influences the soil’s micronutrient content and will significantly release some of the extractable micronutrients previously sequestered in the dry matter back into the soil with time.
D et al. (Mon,) studied this question.