Comparison of Different Adsorption Equations in Describing Sulphate Adsorption before and after Removal of Organic Matter in Some Alfisols of Orissa

Efficiencies of Freundlich, Langmuir, Temkin and initial mass adsorption equations were compared to describe SO₄^2- adsorption in four Alfisols of Orissa before and after removal of organic matter. There was increase in SO₄^2- adsorption in all the soils after removal of organic matter. It was significant in the Suakati and Badbil soils containing more than 1% organic carbon. The initial mass adsorption equation was the best in describing SO₄^2- adsorption both before and after removal of organic matter as evidenced by its highest average R² and the lowest average SE values of all. The Freundlich equation was superior to the Langmuir and Temkin equations, whereas Temkin equation was superior to the Langmuir one in describing SO₄^2- adsorption before and after removal of organic matter.