Reclamation of Saline-Sodic Soils Using Calcium Compounds

Soil salinity, characterized by the excessive accumulation of soluble salts, is a major constraint to sustainable agriculture in Iran's arid and semi-arid regions. Saline-sodic soils, containing high levels of soluble salts and exchangeable sodium, exhibit poor physical and chemical properties that drastically reduce crop productivity. This study reviews reclamation methods for saline and saline-sodic soils, focusing on chemical amendments such as agricultural gypsum, elemental sulfur, sulfuric acid, ammonium thiosulfate, and organic fertilizers. Novel calcium compounds, including soluble calcium-sulfur solutions and organic calcium soil enhancers, are highlighted for their advantages in effectively replacing sodium with calcium, improving soil health, and enhancing plant tolerance to salinity. Efficient reclamation requires accurate soil characterization, careful amendment selection, timing of application, and safety considerations. Integrating these approaches is essential for improving soil quality, increasing agricultural productivity, and ensuring food security in salt-affected regions.