title: Trophic and stoichiometric consequences of nutrification for the intertidal tropical zoanthid Zoanthus sociatus.
abstract: Zoanthids are conspicuous and abundant members of intertidal environments, where they are exposed to large environmental fluctuations and subject to increasing loads of anthropogenic nutrients. Here we assess the trophic ecology and stoichiometric consequences of nutrient loading for symbiotic zoanthids inhabiting different intertidal habitats. More specifically, we analysed the stable isotope signature (δ13C and δ15N), elemental composition (C, N and P) and stoichiometry (C:N, C:P, N:P) of Zoanthus sociatus differently exposed to nutrification. Results suggest that autotrophy is the main feeding mode of zoanthids and that the effect water nutrient content differently affects the elemental phenotype of zoanthids depending on tidal habitat. Additionally, habitat effects on Z. sociatus P-related stoichiometric traits highlight functional differences likely associated with variation in Symbiodinium density. These findings provide an innovative approach to assess how cnidarian-dinoflagellate symbioses response to ecosystem changes in environmentally dynamic reef flats, particularly nutrient loading.
authors.affiliation: Department of Fish Ecology and Evolution, Center for Ecology, Evolution and Biogeochemistry, Eawag: Swiss Federal Institute of Aquatic Science and Technology, 6047 Kastanienbaum, Switzerland. Electronic address: miguelcleal@gmail.com.
authors.forename: Miguel C
authors.initials: MC
authors.lastname: Leal
authors.affiliation: Departamento de Biologia & CESAM, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
authors.forename: Rui J M
authors.initials: RJM
authors.lastname: Rocha
authors.affiliation: Department of Fish Ecology and Evolution, Center for Ecology, Evolution and Biogeochemistry, Eawag: Swiss Federal Institute of Aquatic Science and Technology, 6047 Kastanienbaum, Switzerland; Department of Aquatic Ecology, Center of Ecology, Evolution and Biogeochemistry, Eawag: Swiss Federal Institute of Aquatic Science and Technology, 6047 Kastanienbaum, Switzerland; Division of Aquatic Ecology and Macroevolution, Institute of Ecology and Evolution, University of Bern, 3012 Bern, Switzerland.
authors.forename: Jaime M
authors.initials: JM
authors.lastname: Anaya-Rojas
authors.affiliation: Laboratorio de Manejo, Ecologia e Conservação Marinha, Instituto Oceanográfico, Universidade de Sao Paulo, Praça do Oceanogrófico, 191, Cidade Universitaria, 05508-120 São Paulo, SP, Brazil.
authors.forename: Igor C S
authors.initials: ICS
authors.lastname: Cruz
authors.affiliation: Centre Scientifique du Monaco, Equipe écophysiologie, 8 Quai Antoine ler, MC-98000, Monaco, Monaco.
authors.forename: Christine
authors.initials: C
authors.lastname: Ferrier-Pagès
mesh_terms: D000818:Animals; D037421:Anthozoa; D002244:Carbon; D004141:Dinoflagellida; D004463:Ecology; D017753:Ecosystem; D004777:Environment; D007554:Isotopes / Q000032:analysis; D009584:Nitrogen; D010758:Phosphorus
chemical_list: D007554:Isotopes; D010758:Phosphorus; D002244:Carbon; D009584:Nitrogen
keywords: Aerial exposure; Ecological stoichiometry; Eutrophication; Stable isotopes; Tidal pool; Zoanthus sociatus