Clay mineralogy of the salt-affected soils of South-West Punjab

Clay mineralogy of four typical salt-affected soils representing severly saline-sodic (Dagru silt loam) and moderately saline sodic (Kaoni sandy loam) qualifying for Natric Haplustept and Severly saline soils (Sango Dhoan silt loam) and slightly saline soils (Udaikaran silt loam) qualifying for Typic Haplustept was investigated by X-ray diffraction and chemical techniques. Mica (illite) was the dominant clay mineral in all the four great groups of soils followed by kaolinite. Other minerals present were chlorite, vermiculite, calcite, feldspar (K), sepiolite and anatase. The relative similarities in the mineralogy of these alluvium derived soils irrespective of the degree of pedogenesis suggested that all the clay minerals were inherited from the parent material with very little in situ transformation under prevailing conditions.