Distribution of Potassium in Submountaine Tract of Punjab

Soils of the Submountain tracts (Kandi area) of Punjab has not so far been extensively exploited for crop production. With increase in irrigation facilities, the cropping intensity in these areas will increase resulting higher demand for K from the soil. These soils are generally light in texture, low in organic carbon, have low cation exchange capacity, slightly alkaline in pH, calcareous and have low content of soluble salts. In surface soils of unit-I, unit-II and unit-III, the water soluble K ranged from 7.5 to 95.0, 8.0–72.5 and 8.0 to 61.9 mg kg⁻¹, ammonium acetate extractable K ranged from 27.5 to 377.5, 32.5 to 267.5 and 27.5 to 292.5 mg kg⁻¹ and boiling nitric acid soluble K ranged from 680 to 2020, 400 to 1600 and 460 to 1720 mg kg⁻¹ respectively. The potassium content increased with depth in BS-I unit. The K content in the soil profile depended on the texture and the organic carbon content of the soil. The soils of BS-II unit were most deficient and require immediate K application, the soils of BS-III unit, once brought under extensive cultivation will be depleted at faster rate and the soils of BS-I unit may not require immediate K application.