The study looked at the different forms of potassium in soil in paddy growing areas of Nagpur District. They found that the available potassium was highest in the surface layer compared to the sub-surface layer. Water-soluble and exchangeable potassium decreased from surface to sub-surface layers. Non-exchangeable and lattice potassium levels varied but were generally higher in the surface layer. Overall, the total potassium content in the black soils ranged from 6250 to 8322 mg kg-1 in the surface layer and 6900 to 8140 mg kg-1 in the sub-surface layer.