Caria G. auteur aut IRD Arrouays D. auteur aut IRD Dubromel E. auteur aut IRD Jolivet C. auteur aut IRD Ratié C. auteur aut IRD Bernoux Martial auteur aut IRD Barthès Bernard auteur aut IRD Brunet Didier auteur aut IRD Grinand Clovis auteur aut IRD text journalArticle eng text/pdf born digital access We studied the black carbon (BC) content of ca. 405 samples from French topsoil and artificial soil and carbonate mixtures. Our protocol involved three main steps: (i) decarbonation by HCl, (ii) elimination of non-pyrogenic organic carbon in a furnace at 375 degrees C, and (iii) quantification of residual carbon by CHN analysis. BC content increased for calcareous soils according to their carbonates content. Subsequent analyses confirmed the existence of a methodological artefact for BC determination only in calcareous soils. Decarbonation changes the thermal properties of organic matter, creating more recalcitrant carbon than in the initial sample. Higher CaCO3 and organic carbon content results in a more pronounced artefact. The reversal of the first two steps of the chemo-thermal oxidation method (i. e. thermal oxidation before soil decarbonation) eliminates this artefact. Overall, our results suggest that BC content may have been overestimated in a large number of studies on calcareous soils. specialized Black carbon calcareous soils CTO methods decarbonation thermal oxidation artefact 068 27 3 333-339 2011 0266-0032 https://www.documentation.ird.fr/hor/fdi:010053790 10.1111/j.1475-2743.2011.00349.x 0266-0032 [F B010053790] https://www.documentation.ird.fr/hor/fdi:010053790 https://www.documentation.ird.fr/intranet/publi/2011/09/010053790.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2011-10-06 2017-08-23 fdi:010053790 fre