Caffeinated Forests

In a deteriorated tropical forest in Costa Rica, Rebecca Cole and Rakan Zawahi took 35 truckloads of coffee pulp, spread it onto a degraded pasture, and waited two years to see what would happen.

The results are dramatic: the treated plot is now a small forest, while the control ploy remains dominated by non-native pasture grasses. The case study suggests that agricultural by-products could help speed up forest recovery on degraded tropical lands.

“One of my motivations for becoming a restoration ecologist was growing up in a coffee-growing community in Costa Rica and experiencing first-hand the devastating consequences of deforestation and land degradation,” says Rebecca, a postdoctoral researcher from the Dept. of Natural Resources and Environmental Management, and currently a Restoration Ecologist at the Global Ecosystem Ecology lab at ETH-Zurich. “Finding a potential ‘win-win’ solution for farmers and for the environment is a great positive outcome of this project.”

However, this method may not be the most efficient for Hawaii, since it would likely accelerate the invasion of non-native species, adds Zawahi of the UH School of Life Sciences and Lyon Arboretum.

Indeed, Rebecca, Creighton Litton, and Amanda Knauf of NREM are co-authors on another recent study showing that while reducing soil nutrients slows non-native plant growth more than native plants, adding nutrients has the opposite effect.

* Read the UH News story

* Read the article, “Coffee pulp accelerates early tropical forest succession on old fields,” which appears in a recent Ecological Solutions and Evidence.

* Read the article, “Restoration benefits of soil nutrient manipulation and weeding in invaded dry and wet tropical ecosystems in Hawaiʻi,” which appears in a recent Restoration Ecology.