Variability in Shrink-Swell Potentials in Two Transects on Basaltic Plateau of Wardha District, Maharashtra

Six profiles from two transects representing shrink-swell soils developed on basaltic plateau from Dhavasahetti and Umri villages of Wardha district were examined to identify the relationship of physical and chemical characteristicts that influence mechanical properties and derived equations for predicting shrink-swell potential. These soils are slightly alkaline in reaction, fine loamy on summits to fine texture on middle slopes and foots slopes with increasing bulk densities with depth. The negative correlation of bulk density with organic matter (r = -0.53*) and porosity (r = -0.79**) showed increasing trends of bulk density with decrease in organic carbon content and soil porosity. The variability of liquid lintit and plastic limit was high in B horizon alld was positively correlated with clay, CEC and organic carbon content. The high shrink-swell hazard as indicated by COLE value greater than 0.06 mm cm² was significantly and positively related with soil water held at 1.5 MPa (r = 0.99**). The volumetric shrinkage potential of soils was the function of plasticity index and its relationship is explained with a second degree polynomial regression equation having a coefficient of determination (R²) of 0.94 as Volu1l\etric shrinkage potential (Y) = -0.023 + 0.71 (Plasticity index) + 0.034 (plasticity index)².