Increased Atmospheric Carbon Dioxide Stimulates Soils To Release, Not Store, CO2

"Researchers at the Smithsonian Environmental Research Center report the results of a six-year experiment in which doubling the atmospheric greenhouse gas carbon dioxide (CO2) in a scrub oak ecosystem caused a reduction in carbon storage in the soil." "We were surprised to find that these soils were losing soil carbon despite the fact that there was more plant growth," said Patrick Megonigal, a microbial ecologist at SERC and one of the study's authors. "We thought that higher plant growth at elevated CO₂ would either add more carbon to soils, or at least leave it the same. We now need to consider a third possibility--the carbon already in soils will end up back in the atmosphere as a greenhouse gas."