Forms and distribution of potassium in some soils of Hooghly district of West Bengal

Potassium, the third major nutrient, exists in soil in different forms and these forms are in a state of quasi-equilibrium with each other. These different forms of potassium and their relationship with various soil properties were studied in seventeen representative soils spreading over seventeen blocks of the Hooghly district of West Bengal. Soils were in general medium in -1 texture and slightly acidic to neutral in reaction. The organic carbon content of the soils varied from 5.54 to 12.5 g kg in surface soils, being higher than the values for sub-surface soils. The distribution of the different forms of the K in these soils, i.e., -1 available, water soluble, exchangeable, non-exchangeable, total and lattice forms ranged from 86.9 to 132.4 mg kg , 15.4 to 48.2 -1 -1 -1 -1 -1 mg kg , 68.9 to 80.9 mg kg , 658.9 to 764.5 mg kg , 15579.2 to 17250.2 mg kg and 14801.3 to 16361.0 mg kg respectively, for -1 -1 -1 -1 -1 surface soil and 98.5 to 135.6 mg kg , 21.5 to 49.1 mg kg , 72.9 to 92.2 mg kg , 701.0 to 789.9 mg kg , 15753.5 to 17303.2 mg kg -1 and 14951.3 to 16378.4 mg kg respectively, for sub-surface soil. Correlation study showed that the various forms of K were positively and significantly correlated amongst themselves and with CEC, clay and silt content of the soils and negatively correlated with sand content of the studied soil.