Salinity and aridity are two interrelated problems rapidly expanding in Ethiopia, and soil with saline sodic property in Amibara irrigated farms threatens crop productivity. The purpose of the experiment is to evaluate saline-sodic soil using a combination of organic and inorganic amendments. A factorial experiment was laid out in Randomized Complete Block Design with three replications. A field experiment was conducted at the Werer Agricultural Research Center, to evaluate the ameliorative effects of gypsum and filter cake on saline-sodic soil. Composite surface soil samples before the experiment were collected, and after lab analysis, the soil gypsum requirement was calculated. After post-harvesting, plot-level samples were collected for laboratory analysis. The analysis result revealed that bulk density, total porosity, soil pH, exchangeable and soluble cations, and SAR (sodium absorption ratio) were reduced by the interaction of gypsum and filter cake (P < 0.01). The soil pH (7.76) was reduced 5.36% compared to control plots when plots treated with 75% gypsum requirement with 25 t ha-1 filter cakes. The interaction effect of gypsum with filter cake is also highly significant (P < 0.01) on wheat grain yield and biomass. An important conclusion is that the interaction of 75% gypsum with 25 t ha-1 filter cake can improve the physicochemical properties of saline-sodic soil.
amelioration; exchangeable cations; salt-affected soil