TILLAGE EFFECTS ON CROP YIELD AND PHYSICOCHEMICAL PROPERTIES OF SODIC SOILS

Tillage modifies soil structure and has been suggested as a practice to improve physical, hydrological and chemical properties of compacted soils. But little is known about effect of long-term tillage on physicochemical soil properties and crop yield on sodic soils in India. Our objective was to investigate the effect of different tillage regimes on crop yield (wheat and paddy rice) and physicochemical properties of sodic soils. Two sodic sites under conventional tillage for 5 (5-YT; 5-year tillage) and 9 (9-YT; 9-year tillage)years were selected for this study. Changes in crop yield and physicochemical soil properties were compared with a control, sodic land without any till history, that is, 0-year tillage/untilled (0-YT). Five replicated samples at 0- to 10-cm and 10- to 20-cm soils depths were analysed from each site. In the top, 0- to 10-cm soil depth 5-YT and 9-YT sites had higher particle density (Pd), porosity, water holding capacity, hydraulic conductivity, organic carbon, total nitrogen (N-t), available nitrogen (N-avail), phosphorus (P-avail) and exchangeable calcium (Exch. Ca++) than 0-YT, whereas bulk density (Bd), C:N ratio and CaCO3 were significantly lower. Bd, pH, EC and CaCO3 increased significantly with depth in all the lands, whereas Pd, porosity, water holding capacity, hydraulic conductivity, organic carbon, N-t, N-avail, P-avail and Exch. Ca++ decreased. We conclude that continuous tillage and cropping can be useful for physical and chemical restoration of sodic soils. Copyright (c) 2014 John Wiley & Sons, Ltd.