Chevallier Tiphaine auteur aut IRD Woignier Thierry auteur aut IRD Toucet Joële auteur aut IRD Blanchart Eric auteur aut IRD text journalArticle eng text/pdf born digital access Despite the outstanding potential of Andosols for soil organic carbon (SOC) sequestration, the importance of the different mechanisms involved in protecting SOC against mineralization is still unclear. Previous studies have described allophane particles as having a fractal structure. One hypothesis is that SOC is adsorbed or trapped in this fractal structure and could be less available to microbes and enzymes. This paper aims to determine the fractal structure of allophanic soils, especially in mesopores (2-50 nm), and to establish a correlation between the SOC bioavailability and the fractal features of the allophane aggregates. The present study confirms the fractal structure of allophane aggregates. The structural features of the pores, measured using N-2 adsorption-desorption curves and SAXS for the nano-scale range, showed correlation with SOC bioavailability. SOC bioavailability decreased with the extent of the fractal structure. specialized Soil organic carbon Mesopore structure Allophane dV/dR Fractal pore structure SOC bioavailability 068 159 1-2 182-188 2010 0016-7061 https://www.documentation.ird.fr/hor/fdi:010052892 10.1016/j.geoderma.2010.07.010 0016-7061 [F B010052892] https://www.documentation.ird.fr/hor/fdi:010052892 https://www.documentation.ird.fr/intranet/publi/2010/11/010052892.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2010-12-03 2017-08-23 fdi:010052892 fre