Why climate change means a rethink of coffee and cocoa production systems

Both crops are mostly grown under agroforestry management – where trees are incorporated into farming systems. "Coffee and cocoa are both traditionally grown under tree shade in order to reduce heat stress and conserve soil, but the shade trees are typically ignored in most future climate change studies," says Roeland Kindt, Senior Ecologist at World Agroforestry. The agroforestry approach also brings additional ecosystem services, which make the production system more resilient, for example, by conserving water and providing habitats for birds and insects which can act as natural pest predators.

"Agroforestry systems are clear examples of how positive interactions between plants can ameliorate harsh growing conditions and facilitate agricultural productivity. Our study explores which tree species may be more successful in future coffee and cocoa plantations to create more benign microclimates" says Milena Holmgren, expert on ecosystem resilience to climate variability, at Wageningen University.

When the researchers examined the top ten trees currently present in coffee and cocoa agroforestry systems, worryingly they identified that they are the ones most vulnerable to climate change. The authors found that the distribution range of almost 80% of tree species in coffee areas and 62% on cocoa areas will drastically shrink. These include tree species that are important for fruit (e.g. mango, guava and avocado) and timber (e.g. cedar), as well as an estimated 56% loss of nitrogen-fixing trees (e.g. poró and guama), which have the ability to enhance soil productivity and conservation. "Despite the concerning decrease in tree suitability, our study provides alternatives for coffee and cocoa agroforestry under the climate emergency faced by farmers today," adds Kauê de Sousa.

Transforming agroforestry systems by changing tree species composition remains the best bet to adapt most of the coffee and cocoa farms across Mesoamerica, the study recommends. This would involve urgent changes to land use planning, incorporating diversified tree species and including underutilised species into redesigned agroforestry systems. The seed sector also needs to step up by offering farmers seeds and seedlings of the most suitable tree species for each climatic zone. The farmers also need to get on board.

"Farmers need to rethink current agroforestry species composition and use a portfolio that is suitable in the future climate. This is a challenging task, because it takes a long time for farmers to see their investments bearing fruit," explains de Sousa. "We identified that this potential may rely on currently underutilised tree species, such as June plum, sapodilla and breadnut; species that are currently present in coffee and cocoa systems, but in low densities, as they are mainly remnants of previous farm vegetation rather than being actively planted and managed by farmers."

Jenny Ordoñez, Senior Author, concludes: "This study is a very useful first step to improve the design of agroforestry systems as it shows a window of opportunities to maintain diversified agroforestry systems using underutilized species or novel combinations of species. It also opens new areas of research to promote the use of underutilized species which will maintain their suitability under climate change."