Shade-Grown Coffee Farms Support Biodiversity

Shade-grown coffee farms support native bees that help maintain the health of some of the world's most biodiverse tropical regions, according to a study published n the Proceedings of the National Academy of Sciences.

Researchers at the University of Michigan University of California, Berkeley found that by pollinating native trees on shade-coffee farms and adjacent patches of forest, the bees help preserve the genetic diversity of remnant native-tree populations.

"A concern in tropical agriculture areas is that increasingly fragmented landscapes isolate native plant populations, eventually leading to lower genetic diversity," the researchers wrote. "But this study shows that specialized native bees help enhance the fecundity and the genetic diversity of remnant native trees, which could serve as reservoirs for future forest regeneration."

Approximately 32.1 million acres of tropical forest are destroyed annually by the expansion of cropland, pasture and logging. Often grown adjacent to remnant forest patches, coffee crops cover more than 27 million acres of land in many of the world's most biodiverse regions. Over the last 30 years, many Latin American coffee farmers have abandoned shade-growing techniques, in which plants are grown beneath a diverse canopy of trees. In an effort to increase production, much of the acreage has been converted to "sun coffee," which involves thinning or removing the canopy.

Previous studies reveal that shade-grown farms boost biodiversity by providing a haven for migratory birds, nonmigratory bats and other beneficial creatures. Shade-coffee farms also require far less synthetic fertilizer, pesticides and herbicides than sun-coffee plantations.

Sources:

* University of Michigan: Shade-coffee farms support native bees that help maintain genetic diversity in remnant tropical forests