DIFFERENT FORMS OF POTASSIUM IN SOME SOILS OF CENTRAL SOUTHERN NIGERIA

In twenty composite surface (0–15 cm) and sub-surface (15–30 cm) soil samples collected from different locations of Central Southern Nigeria, total, fixed, exchangeable and water soluble K Contents of the soils ranged from 300 to 1400, 27.8 to 109.2, 7.2 to 115 and 1.2 to 18.00 mg/kg, respectively. Clay was negatively and significantly correlated with total K (r = −0.32*) and water soluble K (r = −0.43**) whereas pH was positively and significantly correlated with total K (r = 0.51***). The distribution of K in these soils appeared to be influenced by parent material, its degree of weathering, and pH. Ninety per cent of the soils were deficient in exchangeable K.