Influence of Amendments and Flooding with Saline and Non-Saline Water on Changes in Physico-Chemical Characteristics of a Sodic Soil

Abstract

Laboratory experiments were conducted with a highly sodic soil (pH, 10.6, exchangeable sodium percentage(ESP) 96) to evaluate the effect of amendments viz. gypsum @ 50% gypsum requirements (GR), gypsum @ 100% GR, pyrite equivalent to 50% of GR on sulphur (S) basis, pyrite equivalent to 100% of GR on S basis, farm yard manure (FYM) @ 1%, gypsum @ 50% of GR + FYM @ 1%, gypsum @ 100% of GR + FYM @ 1%, pyrite @ 50% of GR on S basis + FYM @ 1%, Pyrite @ 100% of GR on S basis + FYM @ 1% and a control (no amendment) with saline (ECiw 4 dSm 1) and non saline (EC 0.4 dSm 1) irrigation water on the temporal changes in pH, EC, ESP, exchangeable Ca+Mg, Fe2+ and Mn2+ of the soil. With increase in the incubation period after flooding pH and ESP decreased, whereas EC, Fe2+, Mn2+ and exchangeable Ca + Mg were increased following amendment applications. FYM alone and/or in combination with gypsum and pyrite brought about conspicuous increase in Fe2+and Mn2+, the effects being more pronounced with saline water as compared to non saline water. FYM also proved effective in enhancing the efficiency of gypsum and pyrite for the reclamation of sodic soils.