Trees have been promoted by scientists and the green movement as environmentally friendly components of coffee farms. Consumers feel virtuous as they sip their bird-friendly, organic or rainforest alliance certified cappuccino and connoisseurs appreciate that shade, by prolonging maturation of the bean, improves the coffee’s flavour. But what of the Central American farmer who rarely tastes the high quality coffee exported to Europe and North America? What does he or she know about how trees on his or her farm affect coffee production and the environment?
New research published in the scientific journal Agricultural Systems suggests that farmers know a great deal and that most of it complements what scientists know. Scientist, Carlos Cerdan, and colleagues used systematic methods to explore farmers’ knowledge about the effect of trees on coffee productivity and other ecosystem services in Costa Rica. They revealed that farmers’ knowledge is not only largely complementary to that of scientists, but also differs from that of extension workers and coffee processors. Farmers know a lot about some aspects, like effects of tree shade on coffee production but virtually nothing about other aspects, like coffee quality.
“Combining knowledge from these different scientific and local perspectives can improve the design of development programs and projects in the coffee sector,” explains Cerdan. “This could help producers use trees in their plantations to increase and maintain coffee yield at the same time as enhancing other ecosystem services like water quality, flood and erosion control, carbon storage and biodiversity conservation.”
“Farmers are increasingly recognized as having a key role as ecosystem managers,” says Fergus Sinclair, Research Leader in production ecology at the World Agroforestry Centre and one of the authors of the research.
“The provision of ecosystem services from coffee farms depends on the management decisions that farmers make. In-turn, these decisions are based on what farmers know about the ecosystem services provided by trees in their coffee plantations. Critically, farmers have to manage trade-offs between benefits of trees and competition with coffee production and this varies with altitude, soil type and management practices.”
“What is remarkable,” Sinclair goes on to say “is that farmers recognise more than 10 key attributes of trees, such as leaf size and root depth that vary with species and are related to how the trees provide ecosystem services. They can classify 36 species which they incorporate on their farms in terms of these attributes. The use of a range of species by farmers means that a diversity of tree cover is maintained across their coffee landscapes, which is good for biodiversity.”
Coffee is an important crop in Central America both economically and culturally. In Costa Rica, around 50,000 growers produce over 90,000 tons of coffee beans annually, 85% of which is exported, amounting to annual export revenue of USD $250 million. Traditionally coffee was grown under diverse, dense and largely native tree cover, but since the 1970s many growers have converted to systems with fewer shade trees and more intensive use of agrochemicals. Current research shows that farmers hold knowledge that could be useful in reversing this trend if the right incentives can be provided for them to retain tree diversity. A number of certification schemes attract price premiums and the Costa Rican government has been at the forefront of developing payments for environmental services.
The results of this study show that farmers are well aware of what factors affect coffee productivity as well as how to increase the provision of ecosystem services through incorporating trees within their coffee farms. When it comes to coffee productivity, the farmers know which trees improve soil fertility and protect water resources without casting too much shade, and amongst these, farmers often favoured multi-purpose trees that produce fruit or timber in addition to providing ecosystem services. Similar work with cocoa farmers in West Africa also shows that farmers have a sophisticated understanding of how to integrate trees on their farms.
The farmers encapsulated their knowledge of trade-offs between trees, ecosystem services and coffee productivity in an overall classification of trees as either ‘fresh’ (suitable for integration with coffee) or ‘hot’ (unsuitable) based on their leaf texture and size, foliage density, crown shape and root system attributes.
Sinclair points out that “local knowledge is a vast repository of information of particular relevance to agricultural improvement and environmental protection. We are much more likely to end up with successful development programmes if we start by understanding what farmers do and do not know and then work with them to design schemes that combine their knowledge with science.”
Carlos Cerdan conducted his research as part of a joint doctoral program between Bangor University in the UK and CATIE which is a regional Centre for Tropical Agricultural Research and Higher Education in Central America. Recently, CATIE, based in Costa Rica, began a collaborative arrangement with the World Agroforestry Centre to strengthen agroforestry research in Latin America. Scientists from CIRAD, based at CATIE, were also involved in the research. Carlos Cerdan recently joined the University of Veracruz (Mexico) as an agroforestry researcher on coffee, cocoa and vanilla.
The full article is available (with subscription) from:
Cerdan, C R; Rebolledo, M C; Soto, G; Rapidel, B; Sinclair, F L. Tropical Agricultural Research and Higher Education Centre, Turrialba (Costa Rica) 2012. Local knowledge of impacts of tree cover on ecosystem services in smallholder coffee production systems. Agricultural Systems 110 p. 119-130.
Related articles:
Anglaaere LCN, Cobbina J, Sinclair FL and McDonald MA (2011). The effect of land use systems on tree diversity: farmer preference and species composition of cocoa-based agroecosystems in Ghana. Agroforestry Systems 81(3): 249-265
Soto-Pinto, L., Villavaza-López, V., Jiménez-Ferrer, G., Ramírez-Marcial, N., Montoya, G. and Sinclair, F.L. (2007) The role of local knowledge in determining shade composition of multistrata coffee systems in Chiapas, Mexico. Biodiversity and Conservation 16: 419-436.
