Craig Sams Blog: Bio Char
„If you add 18 to 20 tons of compost per hectare (2.2 acres) of land, only 1 ton of the carbon in the compost stays in the soil. As the compost decays into humus, the rest goes off into the atmosphere as carbon dioxide. With biochar, 10 to 20 percent of the carbon goes off as carbon dioxide after a decade or so but the rest is sequestered in the soil for hundreds if not thousands of years.“