Management of Saline–Sodic Soils Using Compost and Gypsum to Improve Maize and Sorghum Production in Northeastern Ethiopia

Abstract

Soil salinity and sodicity are major constraints to crop production in the irrigated agro‐pastoral systems of northeastern Ethiopia, particularly in the Asaita district of the Afar region. This study evaluated the effectiveness of integrated organic and inorganic soil amendments for improving maize and sorghum production under saline–sodic soil conditions. Field experiments were conducted during 2024–2025 using a randomized complete block design (RCBD) with treatments consisting of different combinations of filter cake compost, gypsum, and salt‐tolerant forage species. Crop yield, yield components, biomass production, and economic returns were assessed to determine agronomic and economic performance. The results showed that the integrated application of compost and gypsum significantly improved crop productivity compared with the untreated control. In the biological reclamation trial, Panicum antidotale + 10 t ha −1 filter cake compost produced the highest maize grain yield (5.47 t ha −1 ) and sorghum grain yield (3.70 t ha −1 ), representing increases of 78% and 311%, respectively, over the control. Similarly, the combined application of 10 t ha −1 gypsum + 10 t ha −1 filter cake compost resulted in the highest grain yields of maize (5.00 t ha −1 ) and sorghum (3.70 t ha −1 ). Maximum above‐ground biomass yields were recorded under P. antidotale + compost treatments, reaching 11.50 t ha −1 for maize and 11.96 t ha −1 for sorghum. The highest net economic benefits were obtained from P. antidotale + 10 t ha −1 compost, yielding 35,230 Ethiopian Birr (ETB) ha −1 for maize and 39,720 ETB ha −1 for sorghum. Among the forage species evaluated, treatment effectiveness ranked as P. antidotale > Sesbania > Crotalaria > Alfalfa > Control. Sorghum consistently outperformed maize under saline–sodic conditions, confirming its greater salinity tolerance. These findings demonstrate that integrating halophytic forage species with compost and gypsum provides an agronomically effective, economically viable, and sustainable strategy for reclaiming saline–sodic soils and enhancing cereal production in northeastern Ethiopia.