Charge Characteristics of Some Soils of West Bengal and Sikkim as Affected by Phosphate Treatment

The zero point charge (ZPC) and the associated surface charge parameters, such as surface potential (Ψ₀), permanent surface cbarge density (σ_p) and variable surface charge density (σ_p) of four surface soils and the corresponding phosphate-treated soils are reported. An increase in negative magnitude of surface potential and surface charge of each soil occurred on phosphate treatment which was interpreted in terms of the concomitant increase of the negative charge of the clay fraction of the given soils on phosphate fixation through ligand exchange mechanism.