Soil Potassium Forms in Relation to Agro-climatic Conditions in Maharashtra

The average contents of various forms of potash in Maharashtra soils were 6.0, 123.3, 52.7, 668-8, 2346.7 and 6878.5 ppm of water soluble, exchangeable, available, fixed, HCl-soluble and total, respectively. When expressed as percentage of total KiO, they were found to constitute 0.08, 2.01, 0 82.11.02 and 37.31, respectively. The lateritic and non-lateritic soils of heavy rainfall zones (Zones I & II) were, in general, found to be poor in different forms of potash whereas the soils of arid to semi-arid zones (Zones IV, V & VI) were higher in all fractions of potash. The soils of transition zone (Zone 111) occupied an intermediate position. The available form of potash was highly correlated not only with water soluble and exchangeable forms but also with the fixed and HCl-soluble forms. The clay fraction of the soil was positively correlated with all the forms of potash but significantly so with HCl-soluble and fixed forms.