Scientists found carbon in soil that covered the Earth thousands of years ago.
These soils could contribute to global climate change if disturbed through "erosion, agriculture, deforestation, mining and other human activities," a University of Wisconsin-Madison news release reported.
"There is a lot of carbon at depths where nobody is measuring," Erika Marin-Spiotta, a University of Wisconsin-Madison assistant professor of geography and the lead author of the new study, said in the news release. "It was assumed that there was little carbon in deeper soils. Most studies are done in only the top 30 centimeters. Our study is showing that we are potentially grossly underestimating carbon in soils."
The soil, dubbed the "Brady soil," is believed to have formed between 15,000 and 13,500 years ago in regions such as Nebraska and Kansas. It was eventually buried by an accumulation of "wind-borne dust."
"Most of the carbon (in the Brady soil) was fire derived or black carbon," Marin-Spiotta, whose team employed an array of new analytical methods, including spectroscopic and isotopic analyses, said in the news release. "It looks like there was an incredible amount of fire."
These types of soils are not believed to be isolated to the Great Plains.
The carbon that has been locked away for thousands of years could be disturbed by human activity, accelerating the effects of climate change.
The soil provides a "snapshot" of what the world looked like thousands of years ago. During this time the glaciers were most likely retreating and wildfires were frequent.
"The world was getting warmer during the time the Brady soil formed," UW-Madison geography Professor and study co-author Joseph Mason, said in the news release. "Warm-season prairie grasses were increasing and their expansion on the landscape was almost certainly related to rising temperatures."
