orange peels before and after costa rica

Credit: Daniel Janzen and Winnie Hallwachs

In 1997-98, orange juice producer Del Oro thought it had scored a win-win deal when it signed an environmental services contract with authorities in charge of a neighboring conservation area called Área de Conservación Guanacaste in northern Costa Rica.  The deal was Del Oro would donate part of their forested land to the Área de Conservación Guanacaste.  In exchange, Del Oro could deposit its orange peel waste for biodegradation, at no cost, on degraded forest land within the park.  The motivation for the agreement orchestrated by husband-wife team Daniel Janzen and Winnie Hallwachs, both dedicated ecologists at the University of Pennsylvania, who worked as researchers and technical advisers for many years at Área de Conservación Guanacaste was to bring life back into the depleted soils of deforested national park lands using the tons of waste orange peels and pulp. But Del Oro found itself fending off attacks by many critics  including politicians, TicoFruit, a rival company and the media, who accused the British-owned company of defiling Costa Rica’s natural legacy and acting as an agent of “environmental neo-colonialism.”

Del Oro tried to defend the deal, but a year later the 20-year contract was reportedly revoked by order of Costa Rica’s Comptroller General.  Jump ahead about 16 years when Timothy Treuer, a graduate student in Princeton’s Department of Ecology and Evolutionary Biology was discussing potential research project ideas with Janzen when the Costa Rica orange peel site came up.  Treuer a co-lead author and a Princeton University research team surveyed the land 16 years after the 12,000 metric tons of orange peels were deposited. The Princeton team results within the 7 acres studied, published in the journal Restoration Ecology, found a 176 percent increase in aboveground biomass of the trees (see photo above which tells the story).

“This is one of the only instances I’ve ever heard of where you can have cost-negative carbon sequestration,” said  Treuer. “It’s not just a win-win between the company and the local park—it’s a win for everyone.”