A double jeopardy: Climate change affects both yield and grain quality of cereals in Ethiopia

The agriculture sector faces significant risks from the impacts of climate change across the world. However, there is limited information on the impacts of climate change on yield components such as grain quality. These yield components have significant implication for mal- and under-nutrition in many parts of Africa especially among children. The aim of this study therefore was to use a crop modelling approach to assess the impacts of climate change on yield and grain quality in Ethiopia. The crop model Decision Support System for Agrotechnology Transfer (DSSAT) was used to assess the spatial and temporal variability of yield and yield components associated with grain quality (canopy N, LAI, Tops N, grain N) for maize in Ethiopia for the 1°C, 1.5°C, and 2°C global warming levels. We find that there is considerable variation in both yield and yield components spatially and over time. Areas in the central and western parts have higher yield and grain quality compared to those in the north and northeast of the country. Yield is positively correlated with LAI, N uptake, canopy N and grain N and negatively with soil N at maturity across the three crops. Under global warming levels, the changes in grain N followed the changes in yield with yield changes being more pronounced than grain N changes in loss areas. The largest changes in grain N occurred where the largest changes in yield also occurred in the northern parts of the country. The impacts on grain N in these areas are less than impacts on yield but these are spatially variable across the country and dependent on the location and the warming levels. We therefore conclude that climate change will have an impact on both the yield and grain quality of maize in Ethiopia . These effects of climate change on grain quality should be accounted for in climate impact studies of food systems to safeguard on health and nutrition aspects of food security especially for vulnerable groups. Future work is required to understand mechanisms of climate change impacts on grain quality aspects.