Title : Using the Yield-SAFE model to assess the impacts of climate change on yield of coffee (Coffea arabica L.) under agroforestry and monoculture systems
Ethiopia economy depends strongly on Coffea arabica production. Coffee, like many other crops, is sensitive to climate change and recent studies have suggested that future changes in climate will have a negative impact on its yield and quality. An urgent development and application of strategies against negative impacts of climate change on coffee production is important. Agroforestry-based system is one of the strategies that may ensure sustainable coffee production amidst likelihood future impacts of climate change. This system involves the combination of trees in buffer extremes thereby modifying microclimate conditions. This paper assessed coffee production under: 1) coffee monoculture and 2) coffee grown using agroforestry system, under: a) current climate and b) two different future climate change scenarios. The study focused on two representative coffee growing regions of Ethiopia under different soil, climate and elevation conditions. A process-based growth model (Yield-SAFE) was used to simulate coffee production for a time horizon of 40 years. Climate change scenarios considered were: Representative Concentration Pathways (RCP) 4.5 and 8.5. The results revealed that in monoculture systems, the current coffee yields are between 1200-1250 kg ha-1 yr-1, with expected decrease between 4-38% and 20-60% in scenarios RCP 4.5 and 8.5, respectively. However, in agroforestry systems, the current yields are between 1600-2200 kg ha-1 yr-1, the decrease was lower, ranging between 4-13% and 16-25% in RCP 4.5 and 8.5 scenarios, respectively. From the results, it can be concluded that coffee production under agroforestry systems has a higher level of resilience when facing future climate change and reinforce the idea of using this type of management in the near future for adapting climate change negative impacts on coffee production.
Keywords: Albizia gummifera, CORDEX, Ethiopia, HADCM3 model, process-based model