When growing coffee conserves biodiversity
Original blog post by Stefanie Neno
There are several ways to grow coffee, from the traditional shaded plantation, where a canopy of trees protects coffee plants from the sun, all the way to intensive, full-sun coffee production, where only coffee plants are grown to, theoretically, increase yields.
Shaded coffee farms do notably better at conserving biodiversity and providing ecosystem services, including pollination, pest control, climate regulation, erosion control, watershed management, and carbon and nutrient sequestration.
Regrettably, however, shade coffee cultivation has decreased by 20% globally since 1996. Many producers have converted to sun coffee, and new coffee-growing countries such as Vietnam, Thailand, and Indonesia have opted up-front for the intensive sun coffee management style.
A disappearing refuge for biodiversity
The role of shade coffee in conserving plant, arthropod, bird, bat, and non-volant mammal diversity has been highlighted since the 1990s.
Migratory birds, for instance, often use shade coffee farms as a “corridor” when moving between temperate and tropical regions. Pollinators, such as butterflies and native bees, also migrate between forest fragments and shade coffee farms.
This role as biological corridor is all the more important as coffee regions often are very close to biodiversity hotspots. In El Salvador, Guatemala, and Costa Rica, for example, more than 30% of the area surrounding coffee regions falls within a 50-kilometer radius of protected areas.
An array of ecosystem services
Ecosystem services such as nutrient management, pollination, pest control, erosion control, watershed management, and carbon sequestration are largely a function of biodiversity levels; and they are worth billions of dollars annually.
We should therefore be particularly concerned with biodiversity declines within coffee systems, as shade coffee is converted to low-shade or full-sun coffee.
Specifically, many shade trees fix nitrogen and can increase the nutrient content of soils.
Coffee also benefits from pollinators that are found in shade coffee systems. On one farm in Costa Rica, enhanced insect pollination increased fruit set and improved coffee yields by more than 20%, worth an estimated US$62,000.
Many organisms, like ants and spiders, help control pests, while birds and bats on shaded farms can significantly improve coffee yields and increase farmers’ income.
Finally, shade systems that include one to three different tree species sequester an additional 53–55 tons of carbon per hectare in aboveground biomass, compared with unshaded coffee monocultures.
Making shade coffee work for farmers
Certification for organic, fair trade, or biodiversity- or livelihood-friendly coffees may raise coffee export prices, but these returns do not always cover the additional costs that farmers incur to obtain the certification.
Specific measures are necessary to help small farmers especially, including combined certification, delayed payment of expenses until after the first year’s harvest, or government subsidies and loans to cover the initial costs of certification and transition.
No doubt, it is difficult for governments and conservation institutes to weigh the benefits of diversified farming approaches, especially since coffee yields are typically assessed independently of yields from timber, other crops, or ecosystem services.
Payments for ecosystem services provide a way for beneficiaries to directly compensate the landowners providing the ecosystem services, and they have been implemented in a number of countries, including Costa Rica, Mexico, and China.
At any rate, successful programs require full stakeholder involvement and the development of sustainable livelihoods for farmers.
See also the post from the University of Texas.
Read the study “Shade Coffee: Update on a Disappearing Refuge for Biodiversity” (BioScience, April 16, 2014) by Shalene Jha (The University of Texas at Austin), Christopher Bacon (Department of Environmental Studies and Sciences, Santa Clara University), Stacy Philpott (University of California, Santa Cruz), V. Ernesto Méndez (University of Vermont), Peter Läderach (International Center for Tropical Agriculture, Nicaragua) and Robert Rice (Migratory Bird Center at the Smithsonian Conservation Biology Institute) at: bioscience.oxfordjournals.org