Ocean acidification rapidly reduces dinitrogen fixation associated with the hermatypic coral Seriatopora hystrix, supplement to: Rädecker, Nils; Meyer, Friedrich Wilhelm; Bednarz, Vanessa N; Cardini, Ulisse; Wild, Christian (2014): Ocean acidification rapidly reduces dinitrogen fixation associated with the hermatypic coral Seriatopora hystrix. Marine Ecology Progress Series, 511, 297-302

• Main Authors: Rädecker, Nils, Meyer, Friedrich Wilhelm, Bednarz, Vanessa N, Cardini, Ulisse, Wild, Christian
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2014
• Subjects: Animalia; Benthic animals; Benthos; Bottles or small containers/Aquaria <20 L; Calcification/Dissolution; Cnidaria; Coast and continental shelf; Growth/Morphology; Laboratory experiment; Other metabolic rates; Seriatopora hystrix; Single species; South Pacific; Tropical; Species; Identification; Treatment; Surface area; Nitrogen fixation rate, integrated per hour; Calcification rate of calcium carbonate; Temperature, water; Irradiance; Salinity; pH; Alkalinity, total; Alkalinity, total, standard error; Aragonite saturation state; Partial pressure of carbon dioxide water at sea surface temperature wet air; Carbonate system computation flag; Carbon dioxide; Fugacity of carbon dioxide water at sea surface temperature wet air; Bicarbonate ion; Carbonate ion; Carbon, inorganic, dissolved; Calcite saturation state; Potentiometric; Potentiometric titration; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. 2010; Ocean Acidification International Coordination Centre OA-ICC; Nils; Pacific; Ocean acidification
• Online Access: https://dx.doi.org/10.1594/pangaea.843730; https://doi.pangaea.de/10.1594/PANGAEA.843730

Since productivity and growth of coral-associated dinoflagellate algae is nitrogen (N)-limited, dinitrogen (N2) fixation by coral-associated microbes is likely crucial for maintaining the coral-dinoflagellate symbiosis. It is thus essential to understand the effects future climate change will have on N2 fixation by the coral holobiont. This laboratory study is the first to investigate short-term effects of ocean acidification on N2 fixation activity associated with the tropical, hermatypic coral Seriatopora hystrix using the acetylene reduction assay in combination with calcification measurements. Findings reveal that simulated ocean acidification ( pCO2 1080 µatm) caused a rapid and significant decrease (53%) in N2 fixation rates associated with S. hystrix compared to the present day scenario ( pCO2 486 µatm). In addition, N2 fixation associated with the coral holobiont showed a positive exponential relationship with its calcification rates. This suggests that even small declines in calcification rates of hermatypic corals under high CO2 conditions may result in decreased N2 fixation activity, since these 2 processes may compete for energy in the coral holobiont. Ultimately, an intensified N limitation in combination with a decline in skeletal growth may trigger a negative feedback loop on coral productivity exacerbating the negative long-term effects of ocean acidification. : In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2015) 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).