Effect of Compost and Gypsum Application on the Chemical Properties and Fertility Status of Saline-Sodic Soil

Abstract

Salt-affected soils are present in Pakistan in significant quantity. This experiment was conducted to assess the effectiveness of compost for reclamation and compare its efficiency with gypsum. For this purpose, various combinations of compost and gypsum were used to evaluate their efficacy for reclamation. A saline-sodic field having <TEX>$pH_s$</TEX> 8.90, <TEX>$EC_e$</TEX> <TEX>$5.94dS\;m^{-1}$</TEX> and SAR <TEX>$34.5(mmol\;L^{-1})^{1/2}$</TEX>, SP (saturation percentage) 42.29% and texture Sandy clay loam, gypsum requirement (GR) <TEX>$8.75Mg\;ha^{-1}$</TEX> was selected for this study. The experiment comprised of seven treatments (control, gypsum alone, compost alone and different combinations of compost and gypsum based on soil gypsum requirements). Inorganic and organic amendments (gypsum and compost) were applied to a saline sodic soil. Rice and wheat crops were grown. Soil samples were collected from each treatment after the harvest of both crops and analyzed for chemical properties (electrical conductivity, soil reaction and sodium adsorption ratio) and fertility status (organic matter, available phosphorus and potassium contents) of soil. Results of this study revealed that compost and gypsum improved chemical properties (electrical conductivity, soil reaction and sodium adsorption ratio) of saline sodic soil to the desired levels. Similarly, all parameters of soil fertility like organic matter, available phosphorus and potassium contents were built up with the application of compost and gypsum.