How Microbes Can Transform Carbon Found Deep in Peatlands
A new multi-platform approach demonstrates the ability to uncover intricate microbial metabolisms in complex peatland soils.
A multi-institutional team of researchers demonstrated the ability of a new multi-platform approach to “dive deep” and uncover complicated metabolic dynamics in complex soil environments in peatlands. Using this technique, the team was able to identify active glucose metabolizers for specific microbial populations, as well as map carbon flow through microbial networks. (Image courtesy of University of Arizona)
A multi-institutional team of researchers demonstrated the ability of a new multi-platform approach to “dive deep” and uncover complicated metabolic dynamics in complex soil environments in peatlands. Using this technique, the team was able to identify active glucose metabolizers for specific microbial populations, as well as map carbon flow through microbial networks.
The Science
Plants release carbon compounds into soil. Some are simple and easily broken down by soil microbes, while others are complex and resist breakdown, and thus accumulate deep in the soil over time. Scientists have long thought that these deep carbon stores remained untouched, but new evidence shows that the addition of a simple sugar (glucose) can induce degradation of refractory carbon compounds stored in deeper regions, potentially causing changes to the carbon cycle. While these are highly complex metabolic interactions, a multi-institutional team of researchers demonstrated that a new multi-platform that uses multiple types of omics can reveal insights about the specific metabolic pathways and mechanisms involved.
The Impact
Peatlands are special wetlands that store huge amounts of carbon. This carbon has remained locked away for thousands of years, helping the carbon cycle remain relatively stable. A multi-institutional team’s research found that when a simple sugar (glucose) is made available, existing microbes will more readily break down carbon found deep in peatlands. Using special tracking tools and a multi-platform study that used multiple omics techniques, the team identified which specific microbes drive this process and how they respond to changing soil resources. Specifically, they successfully identified active glucose metabolizing microorganisms from specific microbial populations and mapped carbon flow through the microbial networks. These new capabilities could be used in the future to study processes for critical minerals and materials extraction or other bioprocesses of economic value in complex carbon-rich soil systems.
Summary
A multi-institutional team of researchers led by the University of Arizona collected peat soil samples from the Marcell Experimental Forest in northern Minnesota and conducted experiments at Pacific Northwest National Laboratory (PNNL). They added glucose (a simple sugar) to both surface and deep peatland soil samples to mimic what could happen if fresh compounds released by plants reach deeply into the soil column. The Environmental Molecular Sciences Laboratory (EMSL), a Department of Energy Office of Science user facility at PNNL, provided critical advanced instruments for tracking chemical compounds, analyzing chemical changes and measuring how much of the labeled glucose was incorporated into different compounds. Collaborators at the Georgia Institute of Technology helped identify which specific microbes were using different compounds and how they were processing them. The team identified the specific metabolizers within microbial populations in deep peat layers that metabolize simple sugars, and they mapped how carbon flows through microbial networks. The byproducts of this type of microbial metabolism can be used by other microorganisms to degrade old, stored carbon. This knowledge can be applied for critical minerals and materials extraction and other processes important for supporting the bioeconomy.
Contacts
Sumudu Rajakaruna
University of Arizona
Malak M. Tfaily
University of Arizona
David Hoyt
EMSL
Funding
This research was supported by the Department of Energy (DOE) Office of Science, Biological and Environmental Research program. A portion of this research was performed at the Environmental Molecular Sciences Laboratory, a DOE Office of Science user facility sponsored by the Biological and Environmental Research program at Pacific Northwest National Laboratory.
Publication
S. Rajakaruna, et al. “Adding labile carbon to peatland soils triggers deep carbon breakdown.” Communications Earth & Environment 5, 792 (2024). [DOI: 10.1038/s43247-024-01954-y]