Potassium desorbtion and sulphate sorption by oxisol and alfisol of Ini Local Government, Akwa Ibom State.

摘要

Potassium desorbtion and sulphate sorption by oxisol and alfisol in tropical soils is highly different and their desorbtion and sorption in the soil profile are yet to be completely known. The effect of pH and SO4= concentration on the amount of SO4= sorbed and on the desorbed potassium of the soil were investigated through equilibrium procedures using soil samples representing one of oxisol and another of alfisol of Ini local government of Akwa Ibom State, Nigeria. The amount of K+ initially present in the equilibrium solution varied from 20 to 24.5 mM/litre when the SO4= concentration increased from 0 to 24 mM/litre. There was a trend for increasing K+ desorbed with increasing SO4= sorption with each sample. The trend was clearer in the B2 horizon of Acrohumox. Equally, the final pH of the equilibrium solution increased when SO4= sorption increased. Under this condition, the increase in sorbed K+ tended to be the result of SO4= sorption directly. When pH was controlled at a constant level of 4.0, there was an increase in K+ retained by the soil with increasing levels of sorbed SO4=. The amount of k desorbed by 0.5 N NH4NO3 was less in all cases showing a high pH dependence of cation. The soils have great opportunities for arable crop production.