Evaluation of soil quality under oil palm cultivation in a coastal plain sands area of Akwa Ibom State Nigeria

There is paucity of quantitative scientific information of the potential of crop plants to improve soil quality in the coastal plain sands area, which can contribute to optimum crop productivity. Accordingly, the study evaluated the influence of oil palm cultivation on soil quality in a coastal plain sands area of Akwa Ibom State, Nigeria. Four oil palm blocks of varying ages: 57 years (B-57), 39 years (B-39), 17 years (B-17) and a no oil palm block (B-0), which served as the control was used for the study. A total of 12 pits were dug. The soils were described according to horizon designation as observed in the soil profile, sampled at both dry and wet seasons, air dried, sieved and taken to the laboratory for analysis. The data obtained were subjected to laboratory analysis. The soil quality evaluation using principal component analysis method, showed that oil palm improved the soil quality in the dry season with the best quality in B-17 (2.34) followed by B-57 (2.14), B-0 (2.0) and B-39 (1.85). After initial improvement in soil quality by oil palm plantation, up to 17 years of age, the soil quality degraded as the oil palm advanced in age up to 39 years, before it improved again such that soil quality was better at 57 years than when it was assessed at 39 years. Irrespective of the age of oil palm plantation, soil quality was degraded by the wet season. The trend (for wet season) was as follows: B-39 >B-17 >B-57= B-0. The study has revealed that oil palm cultivation can serve as a good soil management and conservation practice in the coastal plain sands area, since it has the potential of improving soil quality (physical, chemical and biological) the longer it stays on the soil.