Tropical rainforests are vital to global biodiversity and the carbon cycle, but researchers know relatively little about how nutrients and energy move through the forests.
A team of IBES scholars has come up with a way to improve scientific knowledge in the heart of the Atlantic Rainforest in Bahia, Brazil by studying legumes, plants that make nutrients—literally—out of thin air.
As part of a project designed and led by PhD candidate Lindsay McCulloch and overseen by biogeochemist Stephen Porder, undergraduates Sawyer Balint and Kelsey Fenn had the opportunity to travel to Bahia and participate, hands-on, in fieldwork.
“Eleven different legume species had been grown in a greenhouse under varying water and soil nutrient availability for about four months,” says Balint, who was the most junior member of the team. “We were interested in how changes in environmental factors impacted rates of the nutrient-making process, symbiotic nitrogen fixation.”
The wider project aims to enhance researchers' understanding of how environmental conditions under climate change impact the legumes' ability to function.
As Balint explains, although analyzing symbiotic nitrogen fixation rates for more than 800 individual plants was tedious work, it was immensely rewarding. Ultimately, he says, this sort of work is an essential step toward clarifying the role of tropical nutrient-makers like legumes in the global carbon cycle.
“By better understanding how legumes respond to water and nutrient limitation,” says Balint, “we can make better-informed predictions of how nutrient cycling will be impacted by our changing world.”