Ecological Solutions and Evidence has published a new study exploring the potential of natural organic byproduct for accelerating tropical forest recovery. The study finds that coffee pulp might not only be a more effective fertilizer than previously thought, but it could very well be the key to mass reforestation.
While coffee pulp has long been proposed as a solution for soil degradation in tropical forests, according to researchers Rebecca J. Cole and Rakan A. Zahawi, there is a lack of data on the practical applications of coffee pulp for soil amending.
The two conducted the study on two plots of land in Costa Rica. Both plots were previously used for coffee production and experienced severe deforestation beginning in the 1950s. In 2018, Cole and Zahawi added a half-meter layer of unprocessed coffee pulp to one plot; the other plot was left untreated to serve as the control. The research team then monitored and measured vegetation coverage, tree growth, and soil composition in both plots over the course of two years.
The team found that the study plot treated with coffee pulp showed greater plant diversity, soil quality, and four times the canopy cover compared to the control plot. Trees and shrubs were 30 times the diameter of those in the control group, with four times the canopy height and 20 times the stem density, too. Soil composition measurements found that the study plot contained significantly higher concentrations of carbon, phosphorous, and nitrogen.
Cole and Zahawi emphasize that although these results are promising, more research at different sites around the world would strengthen the case for coffee pulp as a viable and practical solution for soil degradation and deforestation. Similar studies with other types of agricultural byproducts would also allow for comprehensive comparative studies that could benefit both agricultural industries and reforestation efforts at once.