In an effort to offset greenhouse gas emissions and to mitigate climate change, research scientists report that soil in forests can capture and hold a large quantity of atmospheric carbon dioxide. Reforesting lands that have lost their forest cover due to cultivation, clear-cutting or fire could sequester two petagrams – or two billion metric tons – of carbon in soils in a century, which is about 10 percent of total U.S. forest carbon sequestration, said Cornell doctoral candidate Kathryn Hofmeister, a co-author on University of Michigan-led research published in the Proceedings of the National Academies of Science (PNAS), Feb. 26. The study examined the potential to expand the soil carbon sequestration in reforested areas.