Articles >
STATUS OF READILY AND SLOWLY AVAILABLE POTASSIUM IN
SOILS AT INSTITUTIONAL FARMS IN AKWA IBOM STATE, NIGERIA
Author(s): Uduak, I. G. and Joseph, F. I.
Volume/Issue: Volume 6 , Issue 1 (2026)
ABSTRACT:
This study was conducted to evaluate the status of readily and slowly available potassium (K) in soils at some institutional farms in Akwa Ibom State, Nigeria, namely Cross River Basin Development Authority Farm, Abak, Akwa Ibom Agricultural Development Program Farm, Abak, Akwa Ibom State University Commercial Farm, Obio Akpa, University of Uyo Commercial Farm, Use Ufot, and Cross River Basin Development Authority Farm, Itu. Ten composite soil samples obtained from the farms at 0 – 15 cm and 15 – 30 cm were analyzed by the routine methods to determine their physicochemical properties. The readily available K was determined as the sum of the water-soluble and exchangeable K, which were extracted with deionized-water and neutral 1M NH OAc solution respectively. The slowly available K was determined by the boiling 1M 4HNO method. K ion concentrations in all the extracts were measured with a digital photometer. Results 3showed high contents of sand (85.60 – 93.60%), moderate available P (10.02 – 18.20 mg/kg) and low clay (4.20 – 12.20%), OM (1.37 – 2.00%), total N (0.06 – 0.18%), exchangeable bases [Ca (2.10 – 3.30 cmol/kg), Mg (0.72 – 1.50 cmol/kg), K (0.20 – 0.60 cmol/kg) and Na (0.01 – 0.03 cmol/kg)] and ECEC (4.64 – 6.31 cmol/kg). The readily available K (0.23 – 0.63 cmol/kg) levels in most of the soils fell within the normal range for most crops and virtually all the slowly available K (0.23 – 0.80 cmol/kg) levels were low. Regular soil testing, applications of manure/K-rich fertilizer and conservation tillage practices were recommended.
KEYWORDS:
Readily available, nonexchangeable, potassium and soil properties.
