Fromin N. auteur aut IRD Saby N. P. A. auteur aut IRD Lensi R. auteur aut IRD Brunet Didier auteur aut IRD Porte B. auteur aut IRD Domenach A. M. auteur aut IRD Roggy J. C. auteur aut IRD text journalArticle eng text/pdf born digital access Understanding the pattern in spatial distribution of soil microbial processes is critical to understand the environmental factors that regulate them as well as to scale up these processes to ecosystem. Soil samples from a I ha tropical rainforest plot (Paracou, French Guiana) were analyzed according a nested sampling approach using different separation distances ranging from 0.4 to 40 m. The variability of substrate induced respiration (SIR) and of denitrification enzyme activity (DEA) was characterized in relation to various soil properties (total C and N contents, NIRS related index of soil organic matter quality, SOMQ and index of tree influence potential, IP). The variability of SIR and DEA was higher than that of environmental properties. The patterns of accumulated variance as a function of distance varied among the soil properties. The variability of SIR and DEA mainly occurred at small (1 m) scale (and at the 10-40 m-scales for SIR), probably reflecting the quality of litter input that results of the influence of local assemblage of different tree species, though changes in the soil N and C contents. Indeed, total soil C and N contents explained the microbial properties at every scale. Coefficients of codispersion showed that neither SOMQ nor IP did correlate with SIR and DEA, and confirmed that total C and N contents explained microbial properties in a scale dependent and complex manner. Such spatial dependency underlines the importance of soil heterogeneity in this tropical forest with implications for sampling strategies when studying the microbial processes and their response to disturbances. specialized Soil microbial processes Respiration Denitrification Soil organic matter Tree influence potential Scale dependent process GUYANE FRANCAISE 074 068 082 197 98-107 2013 0016-7061 https://www.documentation.ird.fr/hor/fdi:010060850 10.1016/j.geoderma.2012.12.009 0016-7061 [F B010060850] https://www.documentation.ird.fr/hor/fdi:010060850 https://www.documentation.ird.fr/intranet/publi/2013/05/010060850.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2013-05-31 2017-08-23 fdi:010060850 fre