Evaluation of land suitability areas for irrigation using GIS and AHP-based tools in the case of Zenti River Catchment, Gofa district, Ethiopia

Land potential assessment has enormous use for smallholder farmers for the sustainable utilization of scarce physical land resources. The study area is faced with a significant lack of available studies on irrigation land suitability due to limited information regarding soil and land resources. This scarcity of data poses a significant challenge in effectively assessing the suitability of land for irrigation purposes. The study aimed to assess the land suitability for irrigation in the case of the Zenti River Catchment, Ethiopia. To achieve the objectives, soil properties, land use/cover, slope, and proximity to a perennial river were used. This was accomplished by using the analytical hierarchical process (AHP) and GIS-based tools. Soil samples were collected and used as criteria for irrigation suitability analysis: soil salinity, soil reaction (pH), soil organic matter, soil cation exchange capacity, and soil moisture content. To evaluate the land suitability for irrigation potential, the weighted linear combination analysis of AHP and reclassified thematic layers were overlaid in the Arc GIS tool. The result showed that soil suitability and land slope factors shared higher weights of 40% and 30%, respectively. A large portion of the study area falls in a high (19%) to moderate (37%) irrigation potential zone. Decision-makers can utilize this information to plan and allocate resources for irrigation projects in the most suitable locations. Moreover, smallholder farmers can benefit from understanding, which areas are suitable for irrigation, allowing them to make informed decisions when selecting land for cultivation and adopting proper management.