GIS-based evaluation of agro-environmental factors for teff suitability in the upper blue Nile Basin, Ethiopia

Climate change poses significant risks to rain-fed agriculture, particularly in vulnerable regions such as Ethiopia, where teff (Eragrostis tef) is a staple crop. While existing studies have assessed land suitability at the watershed level, this study provides a comprehensive basin-level analysis using Multi-Criteria Decision-Making and Geographic Information Systems. By integrating climatic, edaphic, and topographic factors, we identify that 32.3% (54,516 km2) of the Upper Blue Nile Basin is highly suitable for teff cultivation, with rainfall emerging as the most influential factor (criteria weight of 0.83). The Analytical Hierarchy Process yielded a Consistency Ratio of 0.08, confirming methodological rigor. Soil texture, bulk density, and depth are critical for water retention and nutrient availability, while soil organic carbon and cation exchange capacity play important roles in soil fertility. Our findings highlight the need for targeted land management practices, such as organic matter addition and sustainable water management, to increase teff yield. A critically important finding is that a large area, 38.3%, is marginally suitable, representing a major strategic opportunity for improvement through targeted interventions. This study provides a spatially explicit framework for agricultural planning, offering valuable insights for policymakers and farmers to mitigate food security challenges in the face of climate change.