Fertilizer, Lime and Manure Amendments for Ultisols Formed on Coastal Plain Sands of Southern Nigeria

Abstract

The highly weathered and leached soils formed on Coastal Plain Sands under excessive rainfall regime in southern Nigeria are Ultisols. The appropriate management practices with which to obtain high crop yields in these soils, characterized by high acidity, nutrient deficiencies and imbalances, should be developed. Surface layer (0-15 cm) samples of soils with extreme acidity (pH 4.0-4.6) formed on Coastal Plain Sands were collected from four locations in southern Nigeria and grown to maize (SUWAN 1-SR-Y) in pots for two cycles of six weeks each to measure the direct and residual effects of applied fertilizer (90 kg N+ 36 kg P+ 60 kg K.ha-1), 2.5 MT.ha-1 lime, 10 MT.ha-1 farm yard manure (FYM) compared to a control. The direct effect of FYM produced the highest dry matter yield while fertilizer and lime did not differ significantly from the control. The residual effects were significant in dry matter yield for FYM in all the soils and for lime in three soils. Lime and FYM increased soil pH and exchangeable bases, reduced iron, manganese and aluminium; fertilizer and FYM raised available P while only FYM increased soil organic matter contents. Application of lime, fertilizer and FYM in all possible combinations compared to the control in one soil showed that FYM + Fertilizer gave the highest maize dry matter yield, improved soil characteristics and would be the recommended nutrient management practice for these acid soils.