Vertical distribution of cations and anions along the slope in a vertisol of dry land areas representing northern dry zone of Karnataka

Abstract

Topography plays an important role in soil formation. It also determines the movement of water and dissolved salts within a soil system. A study was carried out in a vertisol of dryland areas of Hungund taluk. Three soil profiles were identified representing high (P1: 530 m), mid (P2: 520 m) and low (P3: 510 m) elevations and profile samples were collected at 15cm depth intervals. The samples were analysed to assess pH, EC and water extractable cations and anions. The pH of soils of high elevations (P1) were found highly alkaline while, soils of profiles-2 and 3 were moderately alkaline in reactions. Both the soil profiles recorded gradual increase in pH with depth. All the three soil profiles were found non-saline ( Ca2+ > Mg2+ > K+ and Cl- > SO42- > total CO32-+HCO3- respectively. Accumulation of sodium and total carbonates in surface soils at high elevation and their transport to subsurface layers might have induced higher SAR and RSC values. Introduction of irrigation into this black soil area is likely to alter the salt balance and induce salinity/ sodicity though they are non-saline at present.