Investigating the salinity distribution using field measurements in the semi-arid region of southern Ethiopia

This study investigated the distribution of salinity and sodicity in the irrigated areas of Abaya Chamo. Representative water and soil samples were collected from different soil depths (0–30 cm and 30–60 cm). Sodium absorption ratio (SAR), electrical conductivity (Ec), pH, exchange sodium, magnesium, calcium, and potassium cations, and exchange sodium percentage (ESP) of the sampled sites were analyzed for soil salinity classification and severity analysis. The spatial analysis revealed predominant strongly saline (72%) and sodic (71.1%) conditions in the surface layer (0–30 cm), intensifying very strongly saline (78.7%) and sodic (71.9%) conditions at 30–60 cm depth. Combined saline-sodic conditions dominated both layers, increasing from 91.2% at the surface to 97.1% in the deeper layer, indicating severe agricultural limitations. The results show that soil in the catchments of Lakes Abaya and Chamo suffer from different salinity and sodium content classes. Therefore, appropriate remedial measures based on soil salinity and sodium content should be developed to achieve better reclamation, agricultural production, and land sustainability.