Publications des agents du Cirad

Cirad

Exploring adaptation strategies of coffee production to climate change using a process-based model

Rahn E., Vaast P., Läderach P., Van Asten P.J.A., Jassogne L., Ghazoul J.. 2018. Ecological Modelling, 371 : p. 76-89.

DOI: 10.1016/j.ecolmodel.2018.01.009

The response of coffee (Coffea arabica L.) agronomical performance to changes in climate and atmospheric carbon dioxide concentration ([CO2]) is uncertain. Improving our understanding of potential responses of the coffee plant to these changes while taking into consideration agricultural management is required for identifying best-bet adaptation strategies. A mechanistic crop modelling approach enables the inclusion of a wide range of prior knowledge and an evaluation of assumptions. We adapt a model by connecting it to spatially variable soil and climate data, by which we are able to calculate yield of rain-fed coffee on a daily time-step. The model takes account of variation in microclimate and water use as influenced by shade trees. The approach is exemplified at two East African sites with distinctly different climates (Mt. Elgon, Uganda, and Mt. Kilimanjaro, Tanzania) using a global sensitivity analysis for evaluation of model behavior and prior parameter uncertainty assessment. We use the climate scenario driven by the Hadley Global Environment Model 2-Earth System representative for the year 2050 to discuss potential responses of the coffee plant to interactions of elevated [CO2], temperature, and water availability. We subsequently explore the potential for adaptation to this scenario through shade management. The results indicate that under current climatic conditions optimal shade cover at low elevations (1000¿m.a.s.l.) is 50%, provided soil water storage capacity is sufficient, enabling a 13.5% increase in coffee yield compared to unshaded systems. Coffee plants are expected to be severely impacted (ranging from 18% to 32% coffee yield reductions) at low elevations by increased temperature (+2.5¿°C) and drought stress when no elevated [CO2] is assumed. Water competition between coffee and shade trees are projected to be a severe limitation in the future, requiring careful selection of appropriate shade tree species or the adoption of other technologies li

Mots-clés : coffea arabica; arbre d'ombrage; agroforesterie; adaptation aux changements climatiques; résistance à la sécheresse; changement climatique; besoin en eau; stress dû à la sécheresse; république-unie de tanzanie; ouganda; afrique orientale

Documents associés

Article (a-revue à facteur d'impact)

Agents Cirad, auteurs de cette publication :