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Shrink-swell (Vertisols and their intergrades) soils cover an extensive area especially in Peninsular India with smectites as the dominant mineral. It was felt necessary to find out the species of smectites for better management of these soils. Hence, two benchmark Vertisols namely Seloo from Wardha and Saikhindi from Ahmadnagar districts of Maharashtra were chosen for the study. High resolution mineralogical analysis employed through X ray diffraction (XRD) techniques of the silt, total clay and fine clay fractions of both the pedons were carried out along with Greene-Kelly test with only fine clays. Silt (50-2 μm), total clay (<2 μm) and fine clay (<0.2 μm) fractions are dominated by smectite in both the soils; the smectites content increased gradually with decreasing size fraction. The fine clay fractions are mostly composed of smectite with small amounts of vermiculite and traces of chlorite, kaolin and feldspar. Greene-Kelly test indicated that both Seloo and Saikhindi soil fine clays are dominated by beidellite/nontronite over montmorillonite. The Seloo fine clay smectite is composed of 18-26 per cent and 74-82 per cent montmorillonite and beidellite/nontronite, respectively, and for Saikhindi it is composed of 32-41 per cent and 59-68 per cent for montmorillonite and beidellite/nontronite, respectively. However, these fine clay smectites are of low charge dioctahedral nature and therefore may not have any K selectivity. This property appears to have implications in K management of shrink-swell soils of Deccan basalt areas.A study was undertaken in the established benchmark soil series in different agro - ecological sub - regions of Black Soil Regions of India with the objective to assess the urease activity as a function of soil depth, bio - climate, cropping system and land use type. The urease activity declined with increase in soil depth. Maximum activity was restricted within 0–30 cm of soil depth. Cropping systems and bio - climates significantly (p \ 0.01) influenced the urease activity in soil. The average urease activity in different bio - climates was in decreasing order viz. sub - humid (moist)sub - humid (dry)semi - arid (dry) arid. The activity in different cropping systems was in decreasing order viz. legume - sugarcane - cereals - cotton - based cropping system. Higher urease activity was observed in irrigated agro - systems as compared to the rainfed agricultural systems. High management practices increased urease activity as compared to low management. In physical properties, urease activity was negatively correlated with sand, fine clay, bulk density and available water content. Electrical conductivity, calcium carbonate and cation exchange capacity showed negative correlation in chemical properties at all the soil depths.Not Availabl