Seawater carbonate chemistry and Posidonia oceanica epiphytic community composition and mineralogy ...

• Main Authors: Cox, T Erin, Nash, Merinda C, Gazeau, Frédéric, Deniel, M, Legrand, Erwann, Alliouane, Samir, Mahacek, Paul, Le Fur, Arnaud, Gattuso, Jean-Pierre, Martin, Sophie
• Format: Dataset
• Language: English
• Published: PANGAEA 2017
• Subjects: Benthos; Coast and continental shelf; Community composition and diversity; Entire community; Field experiment; Mediterranean Sea; Mesocosm or benthocosm; Other studied parameter or process; Soft-bottom community; Temperate; Type; Treatment; Time point, descriptive; Coverage; Calcium carbonate mass; Magnesium carbonate, magnesite; Asymmetry; Aragonite; Temperature, water; Temperature, water, standard deviation; Salinity; Salinity, standard deviation; Alkalinity, total; pH; pH, standard deviation; Carbonate system computation flag; Carbon dioxide; Fugacity of carbon dioxide water at sea surface temperature wet air; Partial pressure of carbon dioxide water at sea surface temperature wet air; Bicarbonate ion; Carbonate ion; Carbon, inorganic, dissolved; Aragonite saturation state; Calcite saturation state; Experiment; Calculated using seacarb after Nisumaa et al. 2010; Ocean Acidification International Coordination Centre OA-ICC; Ocean acidification
• Online Access: https://dx.doi.org/10.1594/pangaea.880301; https://doi.pangaea.de/10.1594/PANGAEA.880301

Alterations in seagrass epiphytic communities are expected under future ocean acidification conditions, yet this hypothesis has been little tested in situ. A Free Ocean Carbon Dioxide Enrichment system was used to lower pH by a ~0.3 unit offset within a partially enclosed portion (1.7 m3) of a Posidonia oceanica meadow (11 m depth) between June 21 and November 3, 2014. Leaf epiphytic community composition (% cover) and bulk epiphytic mineralogy were compared every 4 weeks within three treatments, located in the same meadow: a pH-manipulated (experimental enclosure) and a control enclosure, as well as a nearby ambient area. Percent coverage of invertebrate calcifiers and crustose coralline algae (CCA) did not appear to be affected by the lowered pH. Furthermore, fleshy algae did not proliferate at lowered pH. Only Foraminifera, which covered less than 3% of leaf surfaces, declined in manner consistent with ocean acidification predictions. Bulk epiphytic magnesium carbonate composition was similar between ... : In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2016) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2017-08-31. ...