Soil carbon debt of 12,000 years of human land use

Researchers found that land use changes associated with planting crops and grazing livestock have caused a loss of 133 billion tons of carbon from soil worldwide over the last 12,000 years, amounting to about 13 years of global emissions at their current levelshttp://m.pnas.org/content/early/2017/08/15/1706103114.full