Ocean acidification affects growth but not nutritional quality of the seaweed Fucus vesiculosus (Phaeophyceae, Fucales)

• Main Authors: Gutow, Lars, Rahman, Mohammed Mofizur, Bartl, Kevin, Saborowski, Reinhard, Bartsch, Inka, Wiencke, Christian
• Format: Dataset
• Language: English
• Published: PANGAEA 2014
• Subjects: Alkalinity; total; standard deviation; Animalia; Aragonite saturation state; Arthropoda; Behaviour; Benthic animals; Benthos; Bicarbonate ion; Bottles or small containers/Aquaria (<20 L); Calcite saturation state; Calculated; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; Carbon/Nitrogen ratio; Carbon/Phosphorus ratio; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Chromista; Coast and continental shelf; Experiment; Figure; Food consumption; Fucus vesiculosus; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Idotea baltica; Idotea emarginata; Incubation duration; Laboratory experiment; Mass; Nitrogen/Phosphorus ratio; North Atlantic; OA-ICC; Ocean Acidification International Coordination Centre; Ochrophyta; Partial pressure of carbon dioxide; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.835334; https://doi.org/10.1594/PANGAEA.835334

Understanding the ecological implications of global climate change requires investigations of not only the direct effects of environmental change on species performance but also indirect effects that arise from altered species interactions. We performed CO2 perturbation experiments to investigate the effects of ocean acidification on the trophic interaction between the brown seaweed Fucus vesiculosus and the herbivorous isopod Idotea baltica. We predicted faster growth of F. vesiculosus at elevated CO2-concentrations and higher carbon content of the algal tissue. We expected that I. baltica has different consumption rates on algae that have been grown at different CO2 levels and that the isopods remove surplus carbon metabolically by enhanced respiration. Surprisingly, growth of F. vesiculosus as well as the C:N-ratio of the algal tissue were reduced at high CO2-levels. The changes in the elemental composition had no effect on the consumption rates and the respiration of the herbivores. An additional experiment showed that consumption of F. vesiculosus by the isopod Idotea emarginata was independent of ocean acidification and temperature. Our results could not reveal any effects of ocean acidification on the per capita strength of the trophic interaction between F. vesiculosus and its consumers. However, reduced growth of the algae at high CO2-concentrations might reduce the capability of the seaweed to compensate losses due to intense herbivory.