Impacts of ocean acidification and warming on Arctic calcifying key species : benthic coralline red alga (Lithothamnion glaciale) and pelagic thecosome pteropods (Limacina helicina & L. retroversa) = Auswirkung von Ozeanversauerung und Ozeanerwärmung auf die Biologie arktischer kalzifizierender Schlüsselarten: Benthische koralline Rotalge (Lithothamnion glaciale) und pelagische thekosmome Flügelschnecken (Limacina helicina & L. retroversa)

• Main Author: Büdenbender, Jan
• Format: Thesis
• Language: English
• Published: 2016
• Subjects: Arctic; Arctic Ocean; Arktis*; Foraminifera*; Limacina helicina; Ocean acidification
• Online Access: https://oceanrep.geomar.de/id/eprint/34706/; https://oceanrep.geomar.de/id/eprint/34706/1/Dissertation_B%C3%BCdenbender.pdf; https://macau.uni-kiel.de/receive/diss_mods_00018424

Over the last two centuries human activities significantly changed the Earth system. Atmospheric CO2 concentrations were increased by ~25% in only 50 years (1965 to 2015) through combustion of fossil fuels and changes in land use. Consequences of these activities are a warming climate and the ‘acidification’ of the world oceans. A doubling of surface ocean carbon dioxide- (CO2) and proton- (H+) and a 40% decrease of the carbonate ion (CO32-) concentrations until the end of this century will probably affect many marine organisms. Due to low temperatures, the Arctic Surface Ocean will be one of the first to experience mean annual corrosive conditions for calcified organisms. This makes the Arctic Ocean a bellwether for global impacts of ocean acidification (OA) on marine life. Biogenic calcium carbonate often establishes ecological functions like being the fundament for species rich habitats in the case of hermatypic corals and crustose coralline algae (CCA) or impacting global carbon cycling embodied by coccolithophores, foraminifera and thecosome pteropods. The marine carbon cycle influences the destination of human CO2 emissions and the development of the global climate. Therefore, the ecological importance of CCA and pteropods, their involvement in the marine carbon cycle and their anticipated vulnerability to OA call for research on their fate in the future ocean. This doctoral thesis investigates the effects of warming and ocean acidification on growth, calcification, dissolution, corrosion and survival of Arctic calcifying keystone species Lithothamnion glaciale (CCA) and Limacina helicina and retroversa (thecosome pteropods).