Mature oak trees might soon help climate researchers create new ways and tools to combat climate change. A study conducted by researchers at the University of Birmingham discovered that an old oak forest bathed in high levels of CO2 had a positive increase of carbon capture.
The 10-year study, which was conducted at the Free-Air CO2 Enrichment (FACE) facility located at the Birmingham Institute of Forest Research (BIFoR) alongside their colleagues from the Western Sydney University, included 175-year old oak trees in one of the world’s biggest experiments looking into the effects climate change has on nature. The researchers measured the oak trees’ photosynthesis rate when faced with high levels of CO2.
“I’m really excited to contribute the first published science results to BIFoR FACE, an experiment of global importance,” Anna Gardner, a researcher from Birmingham, said. “It was hard work conducting measurements at the top of a 25-meter oak day after day, but it was the only way to be sure how much extra the trees were photosynthesizing.”
The study found that the oak trees consistently increased their photosynthesis rate when faced with high levels of CO2. To understand the oak trees’ positive increase of carbon capture, researchers measured “the soil, roots, wood, and leaves of the trees to see where the extra carbon that’s captured ends up, as well as how long it manages to stay within the giant forest,” True Activist reported.
“It’s a delight to see the first piece of the carbon jigsaw for BIFoR FACE fall into place,” Rob MacKenzie, professor and founding director of BIFoR, said. “We are sure now that the old trees are responding to future carbon dioxide levels.”
When the oak trees were exposed to sunlight, “the general harmony between carbon and nitrogen, which are considered key elements, didn’t change within the leaves of the trees,” showing the researchers that the trees found ways to redirect their elements and balance the increase of carbon capture from the air by taking more nitrogen from the soil.
“Previous work at EucFACE measured photosynthesis increased by up to a fifth in increased carbon dioxide,” David Ellsworth, professor and lead scientist at EucFACE, a similar study using an old eucalyptus forest, said. “So, we now know how old forest responds in the warm-temperature climate that we have here in Sydney, and the mild temperate climate of the northern middle latitudes where Birmingham sits.”
While the response of the entire forest ecosystem is “a much bigger question requiring many more detailed investigations,” this particular research conducted in the BIFoR study “could be detrimental to coming up with future effective climate change policies.”
“Our work adds to the small body of results from laboratories-in-the-forest that are essential to guide climate policy,” MacKenzie said.