Clay Mineralogical Composition of Some Soils from Eastern Vidarbha Region of Maharashtra in Relation to Soil Properties

Eastern Vidarbha region of Maharashtra experience subhumid climate with annual rainfall 1250 mm. The soils of the region are mostly developed from weathered granite-gneiss/sandstone/schists or alluvium deposited by the river Wainganga/Pranhita. The soils under study were clay to clay loam textured (Clay 32.10 to 64.10%). These soils had comparatively high sand (10.50 to 40.00 %). The bulk density and hydraulic conductivity ranged between 1.21 to 1.82 Mg m^-1 and 0.490 to 2.50 cm hr^-1, respectively. These soils were neutral to slightly acidic, noncalcareous and free from salt accumulation. Organic carbon was low to moderate. The X-ray diffractograms suggected the dominance of smectite (MgEgly peak around 1.688 to 1.788 nm) in soils from Pawani, Adyal, Tumsar, Mohadi, Lakhani, (Dist. Bhandara), Mul, Chimur and Nagbhid (Dist. Chandrapur). In these soil clay smecite ranged from 46 to 68 per cent. It was also further confirmed by high CEC (40.00 to 51.2 cmol (p+) kg^-1) and fairly high Ca²⁺ and Mg²⁺. The soils from Brahmapuri (Dist.Chandrapur) and Armori (Dist. Gadchiroli) showed the dominance of kaolinite (0.719 nm peak) which was further confirmed by low CEC (20.00 to 23.4 c mol (p+) kg^-1) and low exchangeable Ca²⁺ and Mg²⁺. The soils from Jawahar nagar and Sakoli (Dist. Bhandara) showed mixed mineralogy where smectite, illite and kaolinite ranged between 15 to 24 per cent, 14 to 20 per cent amd 40 to 47 per cent, respectively. The correlation study indicated the significant positive correlation between smectite and bulk density, pH, CEC ex. Ca and ex. Mg where as significant negative correlation was obtained between illite and kaolinite with bulk density, pH, CEC, ex. Ca and ex. Mg.