title: Functional patterns of microbial communities of rhizospheric soils across the development stages of a young mangrove in French Guiana.
abstract: The functional patterns of microbial communities (microbial respiration, enzyme activities, functional diversity) and the relevant physico-chemical characteristics of rhizospheric soils were studied during the process of mudflat colonization by mangrove. The study site is a fringe mangrove stand located in Montabo Bay at Cayenne (French Guiana). It is characterized by different vegetation development stages dominated by an assemblage of Avicennia germinans and Laguncularia racemosa. Rhizospheric and surface soils were collected from three stations based on successional stages of mangrove colonization: pioneer (P), coppice (C), and young forest (F). The microbial functional patterns showed significant progressive shifts along the mangrove vegetation profile. The P stages, those most influenced by tide currents, were macroscopically characterized by hydro-sedimentary instability and micro-phytobenthic colonization of mudflat. This stage, characterized by low total organic carbon (TOC) content and quality, showed the lowest extracellular enzymatic activities and the highest functional metabolic diversities. TOC quality analyses by (13)C CPMAS NMR provided evidence of progressive TOC enrichment and an increasing imprint of aboveground vegetation on C quality as succession occurs. These differences in the origin, amount, and quality of soil organic matter (SOM) of older stages exerted both a quantitative and qualitative control over microbial functional responses. This indicated the enhancement of aboveground-belowground functional linkages, leading to the expression of high decomposition activities and a functional loss and specialization of rhizospheric microbial communities.
authors.affiliation: Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale (IMBE), Aix-Marseille Université, UMR CNRS IRD Avignon Université, Faculté de St-Jérôme, 13397, Marseille Cedex 20, France, mathieu.luglia@imbe.fr.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Luglia
authors.forename: Stéven
authors.initials: S
authors.lastname: Criquet
authors.forename: Max
authors.initials: M
authors.lastname: Sarrazin
authors.forename: Fabio
authors.initials: F
authors.lastname: Ziarelli
authors.forename: Daniel
authors.initials: D
authors.lastname: Guiral
mesh_terms: D032407:Avicennia / Q000254:growth & development* / Q000382:microbiology*; D002244:Carbon / Q000032:analysis; D055598:Chemical Phenomena; D004269:DNA, Bacterial / Q000235:genetics; D017753:Ecosystem; D005616:French Guiana; D006863:Hydrogen-Ion Concentration; D016014:Linear Models; D009682:Magnetic Resonance Spectroscopy; D009584:Nitrogen / Q000032:analysis; D054712:Salinity; D012988:Soil Microbiology
chemical_list: D004269:DNA, Bacterial; D002244:Carbon; D009584:Nitrogen