Organic Wastes and Tropical Forest Restoration

In a recent publication, we documented the benefits of using agricultural waste (specifically, leftover orange peels from a commercial orange juice factory) to promote forest recovery at a site in Costa Rica. While we showed unambiguously positive impacts on soil conditions, forest biomass, and tree diversity, our ability to infer mechanisms behind this recovery was limited because the project was never replicated. It appears our work is one of only a handful of peer-reviewed studies testing the use of unprocessed agricultural waste as part of a tropical forest restoration initiative. We argue that regardless of the mechanism, there are first-principle reasons to expect that minimally processed (and thus low-cost) agricultural wastes could be utilized to accelerate tropical forest restoration in a variety of contexts, potentially creating a new class of biodiversity-friendly carbon offsets that may address previous concerns about linking tropical forestry to global carbon markets. We outline research initiatives that could lead to a richer understanding of when and where it is safe and effective to utilize agricultural and other wastes in tropical forest restoration endeavors.