Occurrence of Relatively Acid Vertisols in Dadra and Nagar Haveli, India

摘要

In India, Vertisols occur mostly in the Peninsular region extending from 8 deg 45' to 26 deg 0' N latitude and 68 deg 01' to 83 deg 45' E longitude. These soils are mostly developed in alluvium derived from Deccan trap basalt (Murthy et al., 1982). The Vertisols so far reported in India have pH varying from 6.5 to 8.3 in the surface horizons, barring the presence of sodium (sodic Vertisols/ highly calcareous soils). However, acid Vertisols (Ahmad, 1985) exist elsewhere and have been recognized as theDystric great group (Soil Survey Staff, 2006) characterized by (i) pH < 4.5 in 0.01 M CaCl_2 (<5.0 in saturated paste), (ii) conductivity of saturated paste extracts <4.0 dSm~(-1) at 25 deg C, and (iii) a total thickness of 25 cm or more within 50 cm of the mineral soils surface. We present new information about the occurrence of relatively acidic Vertisols from an Indian context.