Becker-Heidmann, P., Liang-wu, L., Scharpenseel, H.-W. (1988): Radiocarbon Dating of Organic Matter Fractions of a Chinese Mollisol. Z. Pflanzenernaehr. Bodenk. 151 (1): 37–39.
Humic acids, humins, and the total organic matter of a Mollisol from Inner Mongolia in China were investigated regarding 14C age and δ13C. The 14C age of the total organic matter increases with 69.3 years per cm depth which corresponds to an extremely slow soil development. The humic acids are generally older than the humins. Humins and humic acids are older than the total organic matter, except in the deepest horizon. δ13C does not deviate from that of fresh plant material throughout the profile indicating early protection against further degradation.