Potential impacts of climate change factors and agronomic adaptation strategies on wheat yields in central highlands of Ethiopia

• Published in: Climatic change 2020-04, Vol.159 (3), p.461-479
• Main Authors: Araya, A., Prasad, P. V. V., Gowda, P. H., Djanaguiraman, M., Kassa, A. H.
• Format: Article
• Language: English
• Subjects: Adaptation; Agricultural management; Agricultural production; Agronomy; Atmospheric Sciences; Carbon dioxide; Climate change; Climate change scenarios; Climate Change/Climate Change Impacts; Climate effects; Climate models; Climate prediction; Computer simulation; Crop production; Crop yield; Cultivars; Earth and Environmental Science; Earth Sciences; Environmental impact; Future climates; Genotypes; Global climate; Global climate models; High temperature; Highlands; Performance evaluation; Planting date; Rain; Rainfall; Sensitivity analysis; Simulators; Temperature; Wheat; Wheat yield
• ISSN: 0165-0009; 1573-1480
• DOI: 10.1007/s10584-019-02627-y

The potential impacts of climate change on wheat were assessed for Kulmsa area in central highlands of Ethiopia using the Agricultural Production Systems sIMulator (APSIM)—wheat model. The objectives were to (i) evaluate the performance of wheat under increased temperatures with or without changes in rainfall and carbon dioxide (CO 2 ) levels and (ii) assess the response of different wheat cultivars to projected future climates under improved management practices (optimal nitrogen rate, planting date, and density) (IMPs). The model was first calibrated and used to identify ranges of IMPs. Then, the model was used to (i) conduct sensitivity analysis of wheat in response to assumed elevated temperature (T), with and without change in rainfall and CO 2 level, and to (ii) evaluate average effect of future worst-case climate change scenarios as predicted by an ensemble of three global climate models (GCM) under highest Representative Concentration Pathways (RCP8.5) for three future time frames, NF (2010–2039), MC (2040–2069), and EC (2070–2099). The simulation was evaluated for three wheat cultivars (“early”, “medium”, and “late”) relative to their corresponding baseline values under the selected IMPs. The baseline climate was represented by the long-term (1980–2009) dataset and CO 2 of 360 μmol/mol. Results showed that increased temperature above 4 °C alone had strong negative impacts on yields under the IMPs when CO 2 staying constant at the baseline level. In contrast, climate change simulations with GCM projections under IMPs and elevated CO 2 effect showed that wheat yield remained unchanged (− 0.4 to + 9%) for all three genotypes. This suggests that the IMPs and elevated CO 2 were able to reduce the negative effect of elevated T on wheat yield as T stress did not go beyond optimal T range for wheat. Overall, climate change may not reduce wheat production in the climate of the location of study in the near future, midcentury, or end century.