Experiment: Food availability outweighs ocean acidification effects in juvenile Mytilus edulis, supplement to: Thomsen, Jörn; Casties, Isabel; Pansch, Christian; Körtzinger, Arne; Melzner, Frank (2013): Food availability outweighs ocean acidification effects in juvenile Mytilus edulis: laboratory and field experiments. Global Change Biology, 19(4), 1017-1027

• Main Authors: Thomsen, Jörn, Casties, Isabel, Pansch, Christian, Körtzinger, Arne, Melzner, Frank
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2013
• Subjects: Acid-base regulation; Animalia; Baltic Sea; Benthic animals; Benthos; Bottles or small containers/Aquaria <20 L; Calcification/Dissolution; Charophyta; Coast and continental shelf; Field experiment; Growth/Morphology; Laboratory experiment; Mollusca; Mytilus edulis; Other; Single species; Temperate; Identification; Species; Treatment; Experiment; Length; Length, standard deviation; Calcium carbonate, dry weight; Calcium carbonate, dry weight, standard deviation; Mass; Mass, standard deviation; Station label; Location; Date; Carbon dioxide, partial pressure; Partial pressure of carbon dioxide, standard deviation; pH; Shell length; Carbon, organic, particulate; Carbon, organic, particulate, standard deviation; Nitrogen, organic, particulate; Nitrogen, organic, particulate, standard deviation; Coverage; Coverage, standard deviation; Survival; Survival rate, standard deviation; Calcium carbonate, mass; Calcium carbonate, standard deviation; Haemolymph, pH; Haemolymph, pH, standard deviation; Salinity; Salinity, standard deviation; Temperature, water; Temperature, standard deviation; Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; pH, standard deviation; Alkalinity, total; Alkalinity, total, standard deviation; Calcite saturation state; Calcite saturation state, standard deviation; Aragonite saturation state; Aragonite saturation state, standard deviation; Carbonate system computation flag; Carbon dioxide; Partial pressure of carbon dioxide water at sea surface temperature wet air; Fugacity of carbon dioxide water at sea surface temperature wet air; Bicarbonate ion; Carbonate ion; Calculated using seacarb after Nisumaa et al. 2010; Biological Impacts of Ocean Acidification BIOACID; Ocean Acidification International Coordination Centre OA-ICC; Thomsen; Ocean acidification
• Online Access: https://dx.doi.org/10.1594/pangaea.829723; https://doi.pangaea.de/10.1594/PANGAEA.829723

Ocean acidification is expected to decrease calcification rates of bivalves. Nevertheless in many coastal areas high pCO2 variability is encountered already today. Kiel Fjord (Western Baltic Sea) is a brackish (12-20 g kg-1) and CO2 enriched habitat, but the blue mussel Mytilus edulis dominates the benthic community. In a coupled field and laboratory study we examined the annual pCO2 variability in this habitat and the combined effects of elevated pCO2 and food availability on juvenile M. edulis growth and calcification. In the laboratory experiment, mussel growth and calcification were found to chiefly depend on food supply, with only minor impacts of pCO2 up to 3350 µatm. Kiel Fjord was characterized by strong seasonal pCO2 variability. During summer, maximal pCO2 values of 2500 µatm were observed at the surface and >3000 µatm at the bottom. However, the field growth experiment revealed seven times higher growth and calcification rates of M. edulis at a high pCO2 inner fjord field station (mean pCO2 ca. 1000 µatm) in comparison to a low pCO2 outer fjord station (ca. 600 µatm). In addition, mussels were able to outcompete the barnacle Amphibalanus improvisus at the high pCO2 site. High mussel productivity at the inner fjord site was enabled by higher particulate organic carbon concentrations. Kiel Fjord is highly impacted by eutrophication, which causes bottom water hypoxia and consequently high seawater pCO2. At the same time, elevated nutrient concentrations increase the energy availability for filter feeding organisms such as mussels. Thus M. edulis can dominate over a seemingly more acidification resistant species such as A. improvisus. We conclude that benthic stages of M. edulis tolerate high ambient pCO2 when food supply is abundant and that important habitat characteristics such as species interactions and energy availability need to be considered to predict species vulnerability to ocean acidification. : In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Lavigne and Gattuso, 2011) 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 2014-2-13.