Soil has the ability to store carbon, preventing it from entering the air as the greenhouse gas carbon dioxide and contributing to climate change. No-till farming and gardening—growing crops with little or no tilling or plowing—may be particularly well suited to sequestering carbon, especially when combined with organic practices.
Soil organic carbon (SOC)—carbon that derives from organic materials and is stored or sequestered in soil—accounts for approximately 58 percent of the total organic mass found in soil. It is the largest global pool of terrestrial carbon. But historic levels of soil organic carbon far exceeded modern-day levels. Globally, most agricultural lands have already relinquished approximately 50 to 70 percent of their initial SOC stores. This loss of SOC contributes significantly to the levels of climate-altering carbon dioxide in the atmosphere; approximately 792 billion tons of carbon emissions from 1750 to 1999 can be attributed to the loss of SOC. The depletion continues today, fueled by land-use changes and the regular plowing and tilling of agricultural fields.