Abstract
<title>Abstract</title> <p>Soil salinization is a major constraint to agricultural sustainability and food security in arid and semi-arid regions, including the Abaya–Chamo Lakes Basin in southern Ethiopia. This study examined smallholder farmers’ perceptions of soil salinity and analyzed the determinants shaping their adaptation strategies in irrigated systems. A mixed-methods approach was used. Data was collected from 380 households selected through multistage stratified random sampling across five purposively selected Kebeles. Household surveys were complemented by key informant interviews, focus group discussions, and field observations. Descriptive statistics were used to summarize socio-demographic, farm-level, and institutional characteristics, while a multinomial logistic regression model identified the factors influencing farmers’ adaptation choices. Most farmers perceived soil salinity as severe (85.9%) and chronic (50.5%), although technical awareness of salinity dynamics was only moderate (51.3%). Salinity moderately affected cultivated lands (54.0%), resulting in severe yield losses for major crops, particularly banana (43.2%) and maize (33.9%). Vulnerability was intensified by reliance on on-farm income (47.7%) and low-to-moderate livelihood diversification. Institutional dissatisfaction regarding salinity management support was extensive (71.6%), with a low mean satisfaction score of 1.45 out of 5. Farming experience, landholding size, labor availability, and income diversification significantly influenced adaptation and coping choices. Notably, a capacity–vulnerability paradox emerged, as resource-endowed farmers adopted more advanced measures yet experienced greater absolute income losses. Adaptive capacity alone is not sufficient to offset vulnerability to soil salinity. Strengthening resilience in the basin requires integrated, context-specific interventions that combine technical salinity mitigation, institutional support, and livelihood diversification.</p>