Forms and Distribution of Potassium in Red Laterite Soils of Patigi in North Central Nigeria

The study evaluated the forms and distributions of potassium in red laterite soils. Top soils samples 0 – 30cm, were randomly collected from thirty different major agricultural areas across Patigi LGA of Kwara State. Descriptive statistics was performed while regression analysis was used to assess the correlation between potassium forms. Results showed the exchangeable sodium (Na+) was very low to moderate. The values ranged from 0.00 – 0.27 cmol/kg soil. The exchangeable potassium (K+) of the soils is very low with values of 0.11 – 0.30 cmol/kg. Calcium (Ca2+) values ranged between 0.10 and 5.1cmol/kg soil while magnesium (Mg2+) ranged from 0.1 – 2.9 cmol/kg soil. The total potassium (K) obtained by concentrated perchloric acid (HClO4) had higher values (3.1 – 11.0 cmol/kg of soil) than other potassium types studied. The available potassium (K) was positively and significantly correlated with HCl Extractable K+ (r = 0.98); HNO3 Extractable K+ (r= 0.93) and HCl04 Extractable K+ (r=0.90) at P<0.01. The values of the extractable potassium increased in the order of NH4OAC HNO3< HClO4. The study revealed that Patigi soils are quite low in available K+ content thus, the supplying power of potassium in these soils is low, hence the need for potassium fertilization for a sustainable crop production.