Pedogenesis and Taxonomy of Some Alluvium-Derived Sodic Soils in Punjab

Three reference pedons from the sodic soils representing Kaheru, Langrian and Isri series were investigated for their morphology and physicochemical characteristics in order to evaluate their genesis and classification. The Kaheru series shows the formation of an argillic horizon with weakly oriented clay cutans, dispersion of soil by excessive sodium (ESP>40) and clay migration are responsible for the formation of argillic horizon in these soils. The Langrian series shows the development of a calcic horizon within one metre of the surface. The sodium-rich argillic horizon in Kaheru series and calcic horizon in Langrian series are responsible for decreasing the permeability of these soils and causing accumulation of salts at their surfaces. The associated cultivated Isri series shows the development of cambic horizon. The study suggests the following sequence of pedogenie evolution: Kaheru>Langrian>Isri series. These soils have been classified following the Soil Taxonomy with some modifications regarding the criteria of Salic and Natric horizons.