Humus preservation and build-up in arable land

Soils are the largest terrestrial reservoirs of organic carbon. Agricultural activities influence the humus content and thus the function of soils as a sink for carbon dioxide (CO2). While permanent humus is quite stable, nutrient humus can be directly influenced positively and negatively by management measures (e.g. soil cover, choice of crop type). The carbon content of humus is about 58 %. In Germany, mineral arable soils store an average of 61 tonnes of carbon per hectare in the topsoil (0-30 cm). (Link to info on German Agricultural Soil Inventory).