Heating of Forests Releases Large Amounts of CO2 from Soil, Study Says

An experiment that heated forests in the eastern U.S. by 10 to 20 degrees F led to an increase in the release of carbon dioxide from soils by up to eight times, according to a new study. When researchers from the University of California, Irvine and other institutions subjected experimental forest plots in Wisconsin and North Carolina to extreme warming, they found that woodland soils released unexpectedly large quantities of CO2, a finding that could have major implications as the world continues to warm. Soil, which takes its rich brown color from large amounts of decaying carbon in leaves and roots, stores twice as much CO2 as the atmosphere, and major releases of CO2 from soils could cause temperatures to rise significantly, the researchers said. “This suggests that soils could accelerate global warming through a vicious cycle in which human-made warming releases carbon from soils to the atmosphere, which, in turn, would warm the planet more,” said lead researcher Francesca Hopkins.