A new study from North Carolina State University finds that greenhouse gas (GHG) emissions from standing dead trees in coastal wetland forests – commonly known as “tree farts” – must be taken into account when assessing the environmental impact of the so-called “ghost”. forests.”
In the study, the researchers compared the amount and type of GHG emissions from dead tree snags to emissions from the soil. Although snags did not release as much as soils, they increased GHG emissions from the overall ecosystem by about 25 percent. Researchers say the findings show snags are important for understanding the total environmental impact of the spread of dead trees in coastal wetlands, known as ghost forests, on GHG emissions.
“Even though these dead standing trees don’t emit as much as soils, they still emit something, and they absolutely have to be taken into account,” said lead author of the study, Melinda Martinez, graduate student in forestry and environmental resources in State NC. “Even the smallest fart matters.”
In the study, researchers measured emissions of carbon dioxide, methane, and nitrous oxide from snags of dead pine trees and bald cypress trees in five ghost forests on North Carolina’s Albemarle-Pamlico Peninsula, where the researchers have followed the spread of ghost forests due to the sea level rise.
“The transition from forest to swamp as a result of these disturbances is happening quickly and leaves behind many dead trees,” Martinez said. “We expect these ghost forests to continue to expand as the climate changes.”
Using portable gas analyzers, the researchers measured the gases emitted from snags and soils in each forest in 2018 and 2019. The overall average emissions from soils were about four times higher than the average emissions from snags. over the two years. And while snags don’t contribute as much as soils, the researchers said they contribute significantly to emissions.
In addition to finding that soils emit more GHGs than snags, the work lays the groundwork for researchers’ ongoing work to understand the role snags play in emissions – that they prevent emissions, like corks. , or throw them away like straws. This is an area of future research that they are currently continuing to explore.
“We started this research by asking ourselves: are these snags straws or corks?” said study co-author Marcelo Ardón, associate professor of forestry and environmental sciences at NC State. “Do they make the soil easier to release, or do they hold the gases? We think they act like straws, but like a filtered straw. They change these gases as the gases move through the snags. . “
The study, “Drivers of greenhouse gas emissions from dead standing trees in ghost forests,” has been published online at Biogeochemistry on May 10, 2021. Funding was provided by the National Science Foundation as part of DEB1713592 and a 2019 North Carolina Sea Grant / SpaceGrant.
Source of the story:
Material provided by North Carolina State University. Original written by Laura Oleniacz. Note: Content can be changed for style and length.