Indian Agricultural Research Institute, Delhi
The texture of the soil does not show any regularity with the elevation above mean sea level. Organic carbon and nitrogen contents tend to increase while the pH decreases with increase in altitude. Illite is the dominant clay mineral with association of chlorite and possibly with traces of montmorillonite. The clay seems not to have been formed in situ. The soil of Chatra is alluvial in origin and belongs to the world group of chestnut coloured soils. The soil comes under the order “Entisol”, suborder “Pasamment” and the great soil group “Orthopsamment” according to the soil classification of U.S.D.A. (7th Approximation).
