Modelling Maize Yield Sensitivity to Abiotic Stresses in East Africa: Integration of Crop Modelling and Synthetic Climate Change Scenarios

Abstract Climate change is expected to significantly affect agricultural production in East Africa (EA). In this study, we synthesized the DSSAT-CERES-Maize model calibrated and evaluated experiments to analyze the sensitivity of climatic variables on maize yield in the region. We used calibrated cultivar coefficients of locally adopted varieties in twelve sites across the region. Consequently, we generated synthetic scenarios of precipitation and temperature changes in line with the plausible projections of the Intergovernmental Panel on Climate Change (IPCC) to characterize the impact of climate change on maize production across the region. Our findings reveal that the impacts of climate change are heterogeneous and vary from location to location. The analysis points to adverse effects in the semi-arid zones, with maize production in Katumani (Kenya), Dodoma (Tanzania), and Ruzizi (Rwanda) expected to decline by -25% to -30% under an extreme temperature rise of + 3 °C and a 30% decline in precipitation. The results also reveal that increased precipitation will compensate for yield losses resulting from elevated temperatures in both arid and humid zones. The potential yield gain under increased precipitation and warming is 16%, 18%, and 5% in Katumani, Dodoma, and Morogoro (Tanzania), respectively. The study recommends site-specific soil, water, and land management adaptation strategies. Strategies for soil and water conservation are recommended for dry regions, whereas approaches such as varying sowing dates are recommended for semi-humid to humid zones. Nutrient enhancement and cultivar variation might be feasible in both contexts.