To figure out how to save the wetland forests of the Amazon, an ecologist from Brazil led a massive series of expeditions to sample trees across the vast rain-forest.
Climate extremes like floods and droughts have become ever more frequent and intense in the last two decades in the Brazilian Amazon.
Julia Valentim Tavares, an ecologist and National Geographic Explorer, based at Uppsala University in Sweden explains that seasonal flooding is a key component of Amazonian wetland forests, on which people, plants, and animals have adapted but now climate changes are putting these ecosytems under threat.
“Our ability to predict Amazonian forest responses to these climatic changes is at the moment limited by a strong lack of understanding of the ecophysiological properties driving tree responses to climatic extremes,” she says, adding that to close that knowledge gap, she led a series of expeditions to construct the first pan-Amazonian dataset of tree physiological properties related to water stress spanning nearly 3000 km in the Amazon basin.
“This required an unprecedented field effort where I led several multinational teams of dozens of people over complex, month-long expeditions in Peru, Brazil and Bolivia for an entire year,” she says.
In a 2023 study, Tavares and her team showed for the first time which regions and kinds of trees are at most risk from dying from droughts, ultimately demonstrating how vulnerability to drought underpins carbon storage and species distribution across the basin.
“As part of the National Geographic and Rolex Perpetual Planet Amazon Expedition – which engages several teams conducting their own studies of the impact of climate change on Amazon River Basin from the Andes to the Atlantic, my team is investigating how changes in inundation, precipitation and air temperature can affect the structure, function, and diversity of Amazonian flooded forests.
Tavares explains that she looks at how trees work and how they relate to the forest around them, to understand plant-water relations and the susceptibility of these forests to ongoing and future climate change.
Growing Up in Brazil
Tavares was born and raised in the big Brazilian city of Rio de Janeiro but her grandmother was from the Amazon.
“My heart has always been connected to the Amazon —the forests, the culture, and the people,” she says, “The Amazon is stunning, it is absolutely powerful; being there reminds you of your own smallness in the face of nature’s magnitude.”
Tavares explains that ultimately, it was this passion that led her to pursue biology and for the last 13 years, she’s been dedicated to studying Amazonian forests.
“Science has historically been dominated by white males from the Global North, frequently side-lining perspectives from women, ethnic minorities and people in the Global South, leading to unequal representation and perpetuating colonial approaches to science and policy,” she says.
Tavares explains that when she assembled the National Geographic and Rolex Perpetual Planet Amazon Expedition’s Flooded Forests team, she made sure that women were the majority in the team and/or people with connections to institutions in Northern Brazil, as usually only Brazilian institutions from the southern regions stand out internationally.
“I am a mother of young twins and seeing women, especially mothers, as researchers inspires me to continue pursuing an academic career,” she says, “Hopefully, my own path may now inspire others and open more space for women and researchers from the Global South.”
Monkey Bridges In Brazil
Elsewhere in the Amazon, indigenous groups and researchers are building literal bridges together to help monkeys and other wildlife cross Brazil’s highways.
Brazil has over 2 million kilometers of highways and a 2022 study estimated those roads could be killing 9 million medium to large mammals annually, with some species reaching more than 200,000 individuals per year.
Fernanda Abra, an associate researcher at NGO Instituto de Pesquisas Ecologicas in Brazil says the Reconecta project uses artificial canopy bridges to reduce the deaths of tree-dwelling animals in the Amazon caused by traffic on BR-174, a 3,321 kilometre-long road that connects Roraima state with the rest of the country.
“I truly believe that reducing animal collisions on highways is very important in the fight to reduce biodiversity loss,” she says, adding that the project is being supported by the Waimiri-Atroari indigenous community, which was highly impacted by a surge in illegal deforestation when the highway was constructed in the 1970s.