Soil Factors Affecting Forms of Potassium and Potassium Fixation in Some Arid Soils

Abstract

Different forms of potassium and potassium fixation capacity in relation to soil characteristics in dominant arid soils of Rajasthan have been reported. Mean values of HCI soluble, N HNO. soluble, fixed and available forms in dune and interdunal sand, light brown sandy and brown light loam soils were low than the grey brown soils. The potassium fixation capacity of different soils decreased in the order: Grey brown loam> brown light loam> light brown sandy > dune and interdunal sand. The dune and interdunal soils because of very low clay content showed negative potassium fixation. The clay, silt and organic carbon content of soils significantly affected the relationship between fixed potassium and potassium fixation capacity. Different soil parameters studied accounted for 44.9, 49.6, 53.4 and 72.6 per cent variability in HCI soluble, N HNO. soluble, fixed and available potassium and potassium fixation capacity, respectively. Potassium fixation capacity can be best predicted by the regression equation arrived at as it gives 72.6 per cent variability.