The carbon content of topsoil and its geographical distribution in France

An estimate of organic carbon stored in French soils to a depth of 30 cm wa s made using data from geo-referenced databases. We produced statistics on carbon stocks in soils according to land use, different land uses and soil type. Then, using a combination of maps of soil and land use, we were able to estimate regional and national carbon stocks. This soil carbon map of Fr ance allowed us to identify the main controlling factors of the carbon dist ribution: land use, soil type in some cases, clay content, and elevation. C arbon stocks in French soils were found to be about 3.1 Pg (10(15)g).