The fight against climate warming has an unexpected ally in mushrooms growing in dry spruce forests covering Alaska, Canada, Scandinavia and other northern regions, a new UC Irvine study finds. When soil in these forests is warmed, fungi that feed on dead plant material dry out and produce significantly less carbon dioxide than fungi in cooler, wetter soil. This came as a surprise to scientists, who expected warmer soil to emit larger amounts of carbon dioxide because extreme cold is believed to slow down the process by which fungi convert soil carbon into carbon dioxide.
Knowing how forests cycle carbon is crucial to accurately predicting global climate warming, which in turn guides public policy to curb greenhouse gas emissions. This is especially important in northern forests, which contain an estimated 30 percent of the Earth's soil carbon, equivalent to the amount of atmospheric carbon.
"We don't get a vicious cycle of warming in dry, boreal forests. Instead, we get the reverse, where warming actually prevents further warming from occurring," said Steven Allison, ecology and evolutionary biology assistant professor and lead author of the study. "The Earth's natural processes could give us some time to implement responsible policies to counteract warming globally."
Soils in the far north contain a lot of carbon from dead grasses, trees and shrubs. Like humans, fungi and bacteria in soil use plant carbon as a food source and convert it into carbon dioxide.
Allison and his colleague, Kathleen Treseder, sought to find out what happens to carbon dioxide levels when boreal forest soil not containing permafrost is warmed. About one-third of the world's boreal forests do not contain permafrost, which is mostly located in Alaska, Canada, Western Siberia and Northern Europe. Global warming is expected to hit northern latitudes hardest, raising temperatures between 5 and 7 degrees Celsius by the year 2100.
The scientists conducted their experiment in a spruce forest near Fairbanks, Alaska. They built small greenhouses and identified similar unheated plots nearby to serve as controls. Both plots received equal amounts of water.
In mid-May when growing season began, air and soil temperatures were the same in greenhouses and control plots. When greenhouses were closed, air temperature rose about 5 degrees Celsius, and soil temperature rose about 1 degree.
The scientists took measurements in the greenhouses and unheated plots and found that by growing season's end in mid-August, soil in warmed greenhouses produced about half as much carbon dioxide as soil in cooler control plots.
A soil analysis found that about half as much active fungi were present in experimental greenhouse samples compared with samples from the controls. When fungi dry out, they either die or become inactive and stop producing carbon dioxide, the scientists said.
"It's fortuitous for humans that the fungi are negatively affected by this warming," said Treseder, ecology and evolutionary biology associate professor. "It's not so great for the fungi, but might help offset a little bit of the carbon dioxide we are putting directly into the atmosphere by burning fossil fuels."
This study appeared Nov. 3 in the journal Global Change Biology.
- PHYSICAL SCIENCES
- EARTH SCIENCES
- LIFE SCIENCES
- SOCIAL SCIENCES
Subscribe to the newsletter
Stay in touch with the scientific world!
Know Science And Want To Write?
- Part I: Bee Deaths Mystery Solved? Neonicotinoids (Neonics) May Actually Help Bee Health
- Microwave Electron Guns: A Field-Emission Plug-And-Play Solution
- Ancient Buried Canyon In South Tibet Rules Out Tectonic Aneurysm
- Interstellar Is A Dangerous Fantasy Of US Colonialism
- In A Snowstorm, Do You Want Salt Or Vegetable Juice On Your Road?
- Extraordinary Claims: Review My Paper For $10
- The BPA Paradox – Too Many Studies?
- "Way to miss the point of the article, genius. Let me guess, you call yourself a nice guy?..."
- "Seriously? You reveal the final scene of a movie and yet do not provide a spoiler alert in advance..."
- "Well, that is not a great example. If you prefer basketball, you don't watch the NBA at all. ..."
- "Men are better athletes than women. If someone had a choice between watching the NBA and the WNBA..."
- "Why did you find it interesting? It's a rather bland political statement by someone not even in..."
- Only half of patients take their medications as prescribed
- Rare new species of plant: Stachys caroliniana
- Research shows anti-HIV medicines can cause damage to fetal hearts
- Self-regulation intervention boosts school readiness of at-risk children, study shows
- New terahertz device could strengthen security