Amelioration of saline-sodic soil by flushing and leaching

A field experiment was conducted in saline -sodic soil [ECe, 9.05-12.07 dS m^-1; pHs, 8.95-9.36, Sodium Adsorption Ration (SAR), 95-134.5 (mmol L^-1)^1/2 and Gypsum Requirement (GR) 9.30-13.70 Mg ha^-1] in split plot design at farmer field (Haveli Karim Dad, Pindi Bhattian District Hafizabad). The treatments included (i) amendments i.e. gypsum @ 50 and 100% soil GR and (ii) leaching / flushing with 8 and 12 inches of water (in two and three splits). The applied water (4 acre inches) was either left to leach down vertically (leaching) or drained out after 24 hours under gravitational force in a side channel (flushing) after gypsum application. Rice-wheat-rice rotation was followed during the study. The application of gypsum @ 100% GR significantly increased the biomass, paddy and wheat grain yield than gypsum application @ 50% GR. The effect of three leachings / flushings was significant in first rice crop than two leachings / flushings. The flushing proved helpful in reducing the ECe of soil while vertical leaching accelerated the reclamation process.