title: Seagrass (Posidonia oceanica) seedlings in a high-CO2world: from physiology to herbivory.
abstract: Under future increased CO2concentrations, seagrasses are predicted to perform better as a result of increased photosynthesis, but the effects in carbon balance and growth are unclear and remain unexplored for early life stages such as seedlings, which allow plant dispersal and provide the potential for adaptation under changing environmental conditions. Furthermore, the outcome of the concomitant biochemical changes in plant-herbivore interactions has been poorly studied, yet may have important implications in plant communities. In this study we determined the effects of experimental exposure to current and future predicted CO2concentrations on the physiology, size and defense strategies against herbivory in the earliest life stage of the Mediterranean seagrass Posidonia oceanica. The photosynthetic performance of seedlings, assessed by fluorescence, improved under increased pCO2conditions after 60 days, although these differences disappeared after 90 days. Furthermore, these plants exhibited bigger seeds and higher carbon storage in belowground tissues, having thus more resources to tolerate and recover from stressors. Of the several herbivory resistance traits measured, plants under high pCO2conditions had a lower leaf N content but higher sucrose. These seedlings were preferred by herbivorous sea urchins in feeding trials, which could potentially counteract some of the positive effects observed.
authors.affiliation: Departament of Ecology and Marine Resources, Mediterranean institute for advanced studies (CSIC-UIB), 07190, Esporles, Balearic Islands, Spain.
authors.forename: Gema
authors.initials: G
authors.lastname: Hernán
authors.affiliation: Departament of Global Change Research, Mediterranean institute for advanced studies (CSIC-UIB), 07190, Esporles, Balearic Islands, Spain.|Department of Science, Liberal Arts School. Universidad Adolfo Ibáñez, 2640, Santiago, Chile.|Center of Research and Innovation for Climate Change (CiiCC). Universidad Santo Tomás, Santiago, Chile.
authors.forename: Laura
authors.initials: L
authors.lastname: Ramajo
authors.affiliation: Departament of Global Change Research, Mediterranean institute for advanced studies (CSIC-UIB), 07190, Esporles, Balearic Islands, Spain.|Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, 73100 Lecce, Italy.
authors.forename: Lorena
authors.initials: L
authors.lastname: Basso
authors.affiliation: Stable Isotope Biogeochemistry Laboratory, Andalusian Institute of Earth Science (CSIC-UGR), 18100 Armilla, Granada, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Delgado
authors.affiliation: Departament of Ecology and Marine Resources, Mediterranean institute for advanced studies (CSIC-UIB), 07190, Esporles, Balearic Islands, Spain.
authors.forename: Jorge
authors.initials: J
authors.lastname: Terrados
authors.affiliation: Departament of Global Change Research, Mediterranean institute for advanced studies (CSIC-UIB), 07190, Esporles, Balearic Islands, Spain.|King Abdullah University of Science and Technology (KAUST), Red Sea Research Center (RSRC), Thuwal, 23955-6900, Saudi Arabia.
authors.forename: Carlos M
authors.initials: CM
authors.lastname: Duarte
authors.affiliation: Departament of Ecology and Marine Resources, Mediterranean institute for advanced studies (CSIC-UIB), 07190, Esporles, Balearic Islands, Spain.|Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR, USA.
authors.forename: Fiona
authors.initials: F
authors.lastname: Tomas
mesh_terms: D000222:Adaptation, Physiological; D035961:Alismatales / Q000737:chemistry / Q000502:physiology*; D000818:Animals; D002245:Carbon Dioxide / Q000032:analysis*; D060434:Herbivory; D010788:Photosynthesis; D036226:Seedlings / Q000737:chemistry / Q000502:physiology*
chemical_list: D002245:Carbon Dioxide