How can biodiversity be protected while ensuring the economic well-being of Madagascar's smallholder vanilla farmers? According to a study conducted by the universities of Gottingen, Marburg, and Hohenheim, there is a way. The research team discovered that vanilla plantations established on fallow land produce the same amount of vanilla as those established in the forest. Nature Communications published the findings.
Research Findings:
Researchers recorded crop yields in vanilla agroforestry systems in north-eastern Madagascar, the world's largest vanilla-growing region dominated by smallholder farmers, for this study. They linked these findings to biodiversity as represented by trees, herbaceous plants, birds, amphibians, reptiles, butterflies, and ants.
Cultivation's economic and ecological aspects were combined. The main finding was that increasing vanilla yields had no effect on overall biodiversity. Furthermore, the vanilla harvest from plantations established on fallow land was identical to the harvest from plantations established in the forest.
"The good news is that farmers are not required to clear land in order to achieve high yields. In fact, by cultivating vanilla on fallow land, they can add value for biodiversity "Dr. Annemarie Wurz, a former Ph.D. student in agroecology at Göttingen University and now a postdoctoral researcher at the University of Marburg, is the study's first author.
"In north-eastern Madagascar, vanilla exports provide a significant source of income for tens of thousands of smallholder farmers, and widespread cultivation is a means of escaping poverty." Another argument is biodiversity: growing vanilla in the forest rather than on fallow land resulted in a loss of 23 percent of all species and a 47 percent decrease in endemic species.
The harvest increased when farmers planted the vanilla more densely or increased the length of the vanilla plants, but the number of tree and reptile species decreased. This had no effect on birds, amphibians, butterflies, ants, or herbaceous plants.
"We also discovered that high tree cover on plantations and in the landscape can increase species diversity," says co-author Professor Teja Tscharntke, an agricultural ecologist at Göttingen University.
Professor Ingo Grass, co-author and ecologist for tropical agricultural systems at the University of Hohenheim, adds: "Promoting vanilla cultivation on fallow land is both environmentally and economically beneficial. This helps to further the current UN Decade for Ecosystem Restoration. Furthermore, this study demonstrates opportunities for promoting and conserving biodiversity outside of protected areas."
(Source: University of Gottingen)
