Morphostratification and characterization of Siwalik piedmont of semi-arid tract of Punjab

The piedmont zone, located between the foot hills of lower Siwalik sub-Himalaya and the plains in north-west of Punjab is elongated from north-east to south-east and its average height varies from 250 to 350 m above mean sea level (amsl). To investigate the morphostratigraphy of Siwalik piedmont surface, remotely sensed data of IRS-B, LISS-I have been analyzed. The interpretation of satellite imageries along with toposheets of the area, in conjunction with ground truth checking, based on relief, slope and drainage characteristics, the surface is divided into lower, middle and upper Siwalik piedmont. The major agency in shaping the morphology of the region is fluvial activity which is dependent upon erosion and deposition. The soils of the lower and middle piedmont are finer in texture (loam to clay loam) and those of upper piedmont and rivulets are coarser in texture and the texture is sand to loamy sand and loamy sand to sandy loam, respectively in control section. In general these soils are non-saline and alkaline in nature owing to calcareous nature of the parent material and low organic carbon. Statistical analysis of horizon thickness showed a consistently wide range of variability within different surfaces of Siwalik piedmont as indicated by high standard deviation and coefficient of variation. The statistical calculations also showed highest variations amongst sand, silt, clay, organic matter, pH and electrical conductivity. The moderately developed soils on lower and middle Siwalik piedmont surfaces showed comparatively thicker horizons with moderate pedogenic development viz., formation of altered B (cambic) horizon and qualified for Inceptisols order (Typic Haplustepts). The soils developed on upper Siwalik piedmont showed thinner horizons with minimum solum development and show development of A-C profiles and qualify for Entisols orded (Typic Ustorthents).