Soil Properties and Growth of Maize as Affected by Slope Position and Fertilizer Type on Coastal Plain Sands

Abstract

A study was conducted to determine the effects of slope position and fertilizer type on soil properties and growth of maize (Zea mays) on Coastal Plain Sands of Akwa Ibom State, Nigeria. Results obtained showed that soils of lower slope (LS) had the highest contents of clay and silt compared with those of upper slope (US) position. Bulk density of the upper slope soil and that of the middle slope (MS) soils were significantly higher (P≤0.05) than that of LS soil and subsequently, total porosity and saturated hydraulic conductivity (Ksat) increased downslope. Bulk density of soils that received poultry manure (PM) and NPK+PM were significantly reduced compared to those of NPK and control while total porosity and Ksat of soils that received PM and NPK+PM were significantly higher (P≤0.05) than those of NPK and control. Soils of LS had highest pH, organic carbon, total nitrogen, available phosphorus, ECEC compared to those of MS and US. The application of poultry manure yielded increase in soil pH, soil organic carbon, total nitrogen, available phosphorus and ECEC when compared to soils of NPK and control. Growth of maize obtained with LS were consistently higher than those of the MS and US soils. Soils of LS that received NPK and NPK+PM had consistently similar maize growth, higher than other combinations of slope position and fertilizer type. The complementary application of poultry manure and NPK 15:15:15 can be the best option for increasing the fertility of soils with varying slope positions on Coastal Plain Sands.