When William Farfan-Rios treks through the forests of the Peruvian Amazon and Andes, his work is focused on understanding how tropical trees are responding to climate change. As a biodiversity fellow at Wake Forest University’s Sabin Center for Environment and Sustainability, Farfan-Rios investigates whether tree species in the Andes-Amazon region can adapt to rising temperatures by migrating to higher elevations.
Farfan-Rios began his research career as an undergraduate, assisting with forest monitoring conducted by the Andes Biodiversity and Ecosystem Research Group (ABERG). He later studied under Miles Silman, a professor at Wake Forest University and co-founder of ABERG. The group manages several forest plots across a broad elevational range, from lowland Amazonian forests to high-altitude Andean sites, creating what Farfan-Rios calls “natural laboratories” for studying environmental change.
Describing the unique characteristics of these forests, Farfan-Rios said: “We have this long-standing elevational gradient and, to my knowledge, it’s one of the longest on Earth. It’s estimated that the Amazon harbors around 16,000 tree species. In our transect, in our last study, we documented around 2,500 species.”
The research process involves marking plots in the forest and collecting data on tree growth over time. “We go to the forest with a machete and a compass and we mark our one-hectare plot, then measure the diameter of the trees. Then we collect leaf samples using telescopic pruners. We preserve those samples and send them to our lab in Cusco for identification,” he explained.
Monitoring focuses on adult trees but is expanding to include juvenile trees—the future generation that will shape how forests respond to climate shifts. Preliminary analysis suggests that fast-growing species may be adapting more successfully than others.
Farfan-Rios emphasized that sharing findings with decision makers is essential: “When we perform our research, we think that the end goal is to publish a manuscript and to get a grant, but we are learning that’s not the end. The end is to actually commit the results to the decision makers… so they can improve policy to protect these natural resources.”
A key part of their work tests what scientists call thermophilization—the idea that warm-adapted tree species should become more common as temperatures rise. However, after decades of monitoring both Peruvian and Bolivian transects run by ABERG and partner organizations like Missouri Botanical Garden, Farfan-Rios said: “We found that the average thermophilization process was an order of magnitude slower than the current regional warming rates. We were not expecting this. We basically found that these forests are not adapting fast enough.”
He explained seed dispersal—trees’ main strategy for moving uphill—takes time because it depends on animals or wind.
The implications extend far beyond South America. The Amazon stores significant amounts of carbon both above ground in trees and below ground in soil. If deforestation or mining releases this carbon into the atmosphere, it can accelerate global climate change—a process with worldwide effects.
“Here in Winston-Salem, we wonder how important is the Amazon for us? The Amazon plays a big role in regulating the climate and the carbon cycle… Actions that we’re doing here… have an impact in the Amazon,” Farfan-Rios noted.
Damage from illegal mining removes not only trees but also soil organisms crucial for ecosystem function—a loss challenging to reverse.
Asked about solutions such as planting new trees or reforestation campaigns, Farfan-Rios cautioned about time constraints: “Trees are long-lived organisms… Now warming is happening too fast for the trees to track it.” He added: “Once we identify those trees that are winners in adapting… maybe we can use them to facilitate upslope migration or reforestation campaigns.”
He concluded by stressing why forest preservation matters globally: “We need to save forests because they are a really important component of regulation of the climate, regulation of the water cycle, regulation of the carbon cycle. And if we disrupt… this forest, we will be the ones who suffer.”
