Irvine, Calif. 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 climate-warming 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."
This study appears online Nov. 3 in the journal Global Change Biology.
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 exp
|Contact: Jennifer Fitzenberger|
University of California - Irvine