title: An experimental test of the hypothesis of non-homeostatic consumer stoichiometry in a plant litter-microbe system.
abstract: Stoichiometric homeostasis of heterotrophs is a common, but not always well-examined premise in ecological stoichiometry. We experimentally evaluated the relationship between substrate (plant litter) and consumer (microorganisms) stoichiometry for a tropical terrestrial decomposer system. Variation in microbial C : P and N : P ratios tracked that of the soluble litter fraction, but not that of bulk leaf litter material. Microbial N and P were not isometrically related, suggesting higher rates of P than N sequestration in microbial biomass. Shifts in microbial stoichiometry were related to changes in microbial community structure. Our results indicate that P in dissolved form is a major driver of terrestrial microbial stoichiometry, similar to aquatic environments. The demonstrated relative plasticity in microbial C : P and N : P and the critical role of P have important implications for theoretical modelling and contribute to a process-based understanding of stoichiometric relationships and the flow of elements across trophic levels in decomposer systems.
authors.affiliation: Centre d'Ecologie Fonctionnelle et Evolutive (CEFE), CNRS, 1919 Route de Mende, Montpellier cedex 5, F-34293, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Fanin
authors.forename: Nathalie
authors.initials: N
authors.lastname: Fromin
authors.forename: Bruno
authors.initials: B
authors.lastname: Buatois
authors.forename: Stephan
authors.initials: S
authors.lastname: Hättenschwiler
mesh_terms: D018533:Biomass; D002244:Carbon / Q000378:metabolism; D017753:Ecosystem; D029582:Meliaceae / Q000382:microbiology; D059013:Microbial Consortia / Q000502:physiology*; D009584:Nitrogen / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism; D018515:Plant Leaves / Q000382:microbiology*; D014329:Tropical Climate
chemical_list: D010758:Phosphorus; D002244:Carbon; D009584:Nitrogen