Scharpenseel, H. W., Becker-Heidmann, P. (1999): Carbon sequestration by grassland and woodland soils of different climate zones as revealed by (thin) layer wise carbon-14 dating. – In: Buchanan-Smith, J. G. (Hg.): Proceedings of the XVIII International Grassland Congress, S. ID No. 52. Association Management Centre, Calgary, Canada
Estimates are, that grassland sequesters on ca 3.2 bil ha about 50 Pg C in the biomass, 300-350 Pg C in SOM (soil organic matter), woodland analog on some 4.2 bil ha 360 Pg in the biomass, 785 Pg in the SOM. The SOM-C in grassland is comparable in quantity of C m-2 with C in tropical rain forests’ living biomass (Whittaker & Likens 1973). C14-dating of soils reveals a tendency of higher C-residence time in grassland and former grassland-cropland soils, compared with adjacent woodland soils of about same climate and geomorphology. In (sub)tropical soils C-residence time proved higher in upland soils than in well aerated (puddled) lowland rice soils. 129 (thin)layer wise C14 dated soil profiles of Alfisols, Inceptisols, Mollisols, Spodosols and Vertisols allow in the mostly grassland derived soils (-alf, -oll, -ert) the highest C14 dates, i.e. C-residence times, consequently the steepest regression curves for age versus depth and the highest correlation factors. In grassland and cropland soils, among the soil texture fractions, highest C14 age / C-residence time was obtained from SOM attached to fine silt as well as to clay domains.