ABSTRACT
The study was carried out at university of Benin located in Ovia North East Local Government Area of Edo State. Soil samples were collected from each sites mentioned above (sport complex, project farm, Faculty of Agriculture arboretum and AGR305 farm). The K sorption capacity was determined by equilibrating the samples containing various concentration (0, 20, 40, 60, 80, and 100) mg K L-1, prepared from potassium chloride KCl. The physical and chemical properties of the soils were determined using standard laboratory methods while the Freundlich and Temkin model was used to express the K sorption capacity. It could be concluded that arable land using Freundlich model, has the highest K sorption capacity of 2.048mg/g, compared to forested land, sports land and plantation land which had values of 1.502, 1.179 and 1.028 mg/g respectively. The adsorption energy ranged between 0.291 for plantation land and 0.410 for arable land, while the R2 value was greater than that of 0.912 amongst the different land use. For Freundlich model, the high R2 model which is an indication of goodness of it was 0.912, 0.958, 0.964 and 0.999 for arable land, forested land, sports land and plantation land use respectively, which indicates the robustness of Freundlich model in describing k adsorption process than the Temkin model.
