A team of researchers has discovered a 3,775-year-old log that could help shape future strategies to combat climate change.
Led by Professor Ning Zeng from the University of Maryland, the team’s study, published in the journal Science on September 27, 2024, shows how this ancient log, preserved in low-permeability clay soil, offers valuable insight into an emerging climate solution known as “wood vaulting.”
The log, found in Quebec, Canada, had lost less than 5% of its carbon dioxide since it was buried nearly 4,000 years ago.
The researchers believe this preservation is due to the clay soil, which slowed the log’s decomposition by preventing oxygen, fungi, and insects from reaching it.
This process helps to lock in carbon dioxide, a major contributor to global warming.
Wood naturally absorbs and stores carbon dioxide from the air while trees are alive, making forests a crucial tool in reducing greenhouse gases.
However, when trees die and decompose, the stored carbon dioxide is released back into the atmosphere.
This is where wood vaulting comes in. By burying wood that would otherwise decompose—such as trees destroyed by wildfires, old furniture, or unused construction materials—the carbon remains trapped in the wood, preventing its release into the atmosphere.
“People think it’s easy to just bury wood, but for it to last hundreds or thousands of years, we need the right conditions,” Zeng explained.
The preservation of the ancient log, which Zeng discovered during a wood vaulting pilot project in 2013, demonstrates the importance of finding the right environment for this process to work.
The research team analyzed the structure and chemical composition of the log, comparing it to a freshly cut piece of Eastern red cedar.
The ancient log had maintained much of its original density and strength, proving that it had lost only a small amount of carbon dioxide over nearly four millennia.
Zeng believes that wood vaulting, especially in regions with clay-rich soil, could become a low-cost and widely available climate solution.
Because clay soil is common, this method could be used in many parts of the world.
However, Zeng emphasized that wood vaulting should complement other climate actions, such as reducing greenhouse gas emissions, to be most effective.
The team hopes to continue refining wood vaulting techniques and looks forward to applying their findings to help slow climate change. “It’s an exciting discovery,” said Zeng. “The urgency of climate change makes this work even more important, and we’re eager to see how it can make a real difference.”
This discovery adds a new tool to the growing list of strategies aimed at fighting climate change, offering hope for a more sustainable future.
