Razanamalala K. auteur aut IRD Razafimbelo T. auteur aut IRD Maron P. A. auteur aut IRD Ranjard L. auteur aut IRD Chemidlin N. auteur aut IRD Lelievre M. auteur aut IRD Dequiedt S. auteur aut IRD Ramaroson V. H. auteur aut IRD Marsden C. auteur aut IRD Becquer Thierry auteur aut IRD Trap Jean auteur aut IRD Blanchart Eric auteur aut IRD Bernard Laetitia auteur aut IRD text journalArticle eng text/pdf born digital access The priming effect in soil is proposed to be generated by two distinct mechanisms: 'stoichiometric decomposition' and/or 'nutrient mining' theories. Each mechanism has its own dynamics, involves its own microbial actors, and targets different soil organic matter (SOM) pools. The present study aims to evaluate how climatic parameters drive the intensity of each priming effect generation mechanism via the modification of soil microbial and physicochemical properties. Soils were sampled in the center of Madagascar, along climatic gradients designed to distinguish temperature from rainfall effects. Abiotic and biotic soil descriptors were characterized including bacterial and fungal phylogenetic composition. Potential organic matter mineralization and PE were assessed 7 and 42 days after the beginning of incubation with 13C-enriched wheat straw. Both priming mechanisms were mainly driven by the mean annual temperature but in opposite directions. The priming effect generated by stoichiometric decomposition was fostered under colder climates, because of soil enrichment in less developed organic matter, as well as in fast-growing populations. Conversely, the priming effect generated by nutrient mining was enhanced under warmer climates, probably because of the lack of competition between slow-growing populations mining SOM and fast-growing populations for the energy-rich residue entering the soil. Our study leads to hypotheses about the consequences of climate change on both PE generation mechanisms and associated consequences on soil carbon sequestration. specialized MADAGASCAR 074 068 021 12 2 451-462 2018 1751-7362 https://www.documentation.ird.fr/hor/fdi:010072003 10.1038/ismej.2017.178 1751-7362 [F B010072003] https://www.documentation.ird.fr/hor/fdi:010072003 https://www.documentation.ird.fr/intranet/publi/2018/01/010072003.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2018-02-05 2024-11-08 fdi:010072003 fre