Researchers have discovered a previously unknown group of microbes that are specially suited for the waterlogged, low-oxygen environments found in the tropical peatlands of Peru’s northwestern Amazon rainforest. This latest study reveals that these microbes play a complex role in the carbon cycle and have the ability to either mitigate or exacerbate climate change. Specifically, they can either help lock carbon away for extended periods or emit it back into the atmosphere as greenhouse gases, notably CO2 and methane.
Tiny organisms, many times smaller than grains of sand, can significantly influence vast ecosystems and the Earth’s climate, as indicated by recent research.
A team of researchers from Arizona State University, along with partners from the National University of the Peruvian Amazon, have identified this unique family of microbes that thrive in the challenging conditions of tropical peatlands.
This research highlights that these microbes serve a dual purpose in the carbon cycle, having the potential to either help in long-term carbon stability or release greenhouse gases, such as CO2 and methane, into the atmosphere.
When environmental conditions remain stable, these microbes enable peatlands to act as large carbon reservoirs, sequestering significant amounts of carbon and mitigating climate-related risks. However, environmental changes, including drought or warming trends, can spur their activities, potentially accelerating climate change on a global scale.
If human activities continue to disrupt these natural peatland ecosystems, it could lead to the release of around 500 million tons of carbon by the century’s end, which is approximately 5% of the total annual emissions from fossil fuels worldwide.
“The microbial ecosystem in Amazon peatlands is immense and has been largely overlooked due to its remote locations and under-researched contributions to both local and global environments. Thanks to local collaborations, we can now access and study these vital ecosystems,” said Hinsby Cadillo Quiroz, the leading author of the study and a researcher at the Biodesign Swette Center for Environmental Biotechnology at ASU.
“Our research is unveiling fascinating organisms that are well-suited to this environment, many of which provide essential functions, from stabilizing carbon to detoxifying carbon monoxide, among others.”
Cadillo-Quiroz is also affiliated with the Biodesign Center for Fundamental and Applied Microbiomics and the ASU School of Life Sciences. Michael J. Pavia from ASU is the principal investigator of this study.
The findings, published in the American Society for Microbiology’s journal Microbiology Spectrum, emphasize the critical need to protect tropical peatlands to maintain one of the planet’s most important carbon storage systems and highlight the intricate relationship between microbial life and global climate regulation.
Importance of Peatlands for Climate Stability
The Amazonian peatlands represent one of the largest carbon reserves on Earth, containing an estimated 3.1 billion tons of carbon in their saturated soils—about double the carbon found in all global forests. Peatlands are essential for global carbon storage because their waterlogged conditions slow down the decomposition process, allowing organic matter to build up over millennia. These ecosystems significantly influence greenhouse gas emissions and the broader climate patterns worldwide.
This current study builds on previous research by identifying new microbes from the ancient Bathyarchaeia group, which contributes to the complex network crucial for the ecosystem’s functioning. The remarkable capabilities of these microorganisms in regulating carbon cycling within peatlands are underscored.
These microbes are located in the Pastaza-Marañón Foreland Basin, a significant peatland area in the northwestern Amazon of Peru. Spanning about 100,000 square kilometers, this basin features extensive flooded rainforests and swamps over ancient layers of peat.
These microbial communities consume carbon monoxide, a toxic gas for many species, converting it into energy while simultaneously reducing carbon toxicity in their surroundings. By breaking down carbon compounds, they generate hydrogen and CO2, which other microbes use to produce methane. Their ability to thrive in both oxygen-rich and poor conditions makes them well-suited to the fluctuating environmental conditions typical of the Amazon region.
Nonetheless, changes in rainfall patterns, rising temperatures, and human activities such as deforestation and mining are disrupting this fragile balance, causing peatlands to emit greenhouse gases like CO2 and methane.
Connection to Climate
While tropical peatlands currently function as carbon sinks—absorbing more carbon than they emit—they are increasingly at risk from climate change. Rising temperatures and shifting rainfall could dry out these peatlands, transforming them into sources of carbon emissions.
The potential release of billions of tons of CO2 and methane from peatlands would significantly accelerate global warming, highlighting the urgent need to protect these ecosystems from human activities and climate-related stressors.
The researchers advocate for sustainable land management practices, including reducing deforestation, drainage, and mining activities in peatlands, to safeguard these environments. Comprehensive investigations into microbial communities are also necessary to enhance our understanding of their roles in carbon and nutrient cycling.
Monitoring changes in temperature, rainfall, and ecosystem dynamics is critical for predicting how peatlands will be affected moving forward.
Future Directions
The discovery of highly adaptable peatland microbes furthers our understanding of microbial diversity and highlights the resilience of life in extreme environments. These microbes are integral to addressing global climate challenges, illustrating how even the smallest organisms can have a substantial impact on Earth’s systems.
This research, backed by the National Science Foundation, represents an important leap in understanding the vital role tropical peatlands and their microbial communities play in global carbon cycling. As climate change continues to evolve, these hidden ecosystems may provide valuable insights for protecting our future.
