title: Decline in coccolithophore diversity and impact on coccolith morphogenesis along a natural CO2 gradient.
abstract: A natural pH gradient caused by marine CO2 seeps off Vulcano Island (Italy) was used to assess the effects of ocean acidification on coccolithophores, which are abundant planktonic unicellular calcifiers. Such seeps are used as natural laboratories to study the effects of ocean acidification on marine ecosystems, since they cause long-term changes in seawater carbonate chemistry and pH, exposing the organisms to elevated CO2 concentrations and therefore mimicking future scenarios. Previous work at CO2 seeps has focused exclusively on benthic organisms. Here we show progressive depletion of 27 coccolithophore species, in terms of cell concentrations and diversity, along a calcite saturation gradient from Ωcalcite 6.4 to <1. Water collected close to the main CO2 seeps had the highest concentrations of malformed Emiliania huxleyi. These observations add to a growing body of evidence that ocean acidification may benefit some algae but will likely cause marine biodiversity loss, especially by impacting calcifying species, which are affected as carbonate saturation falls.
authors: Institute of Environmental Science and Technology (ICTA), Universitat Autònoma de Barcelona, ICTA-ICP, Edifici Z, Carrer de les columnes, E- 08193 Bellaterra, Barcelona, Spain; Vrjie Universiteit Amsterdam, Department of Earth Sciences, Faculty of Earth and Life Sciences, de Boelelaan 1085, 1081HV Amsterdam, The Netherlands; Patrizia.Ziveri@uab.cat.
authors: Patrizia
authors: P
authors: Ziveri
authors: Institute of Environmental Science and Technology (ICTA), Universitat Autònoma de Barcelona, ICTA-ICP, Edifici Z, Carrer de les columnes, E- 08193 Bellaterra, Barcelona, Spain;
authors: Marcello
authors: M
authors: Passaro
authors: Università di Palermo, CoNISMa, Dipartimento di Scienze della Terra e del Mare, Via Archirafi 22/28, 90123 Palermo, Italy;
authors: Alessandro
authors: A
authors: Incarbona
authors: Università di Palermo, CoNISMa, Dipartimento di Scienze della Terra e del Mare, Via Archirafi 22/28, 90123 Palermo, Italy;
authors: Marco
authors: M
authors: Milazzo
authors: Plymouth University, Marine Biology and Ecology Research Centre, PL4 8AA Plymouth, United Kingdom; Institut de Recherche pour le Développement, UR 227 CoReUs2, BP A5, 98848 Nouméa, New Caledonia, France.
authors: Riccardo
authors: R
authors: Rodolfo-Metalpa
authors: Plymouth University, Marine Biology and Ecology Research Centre, PL4 8AA Plymouth, United Kingdom;
authors: Jason M
authors: JM
authors: Hall-Spencer
mesh_terms: D059001:Aquatic Organisms / Q000254:growth & development / Q000502:physiology*; D044822:Biodiversity; D002245:Carbon Dioxide / Q000378:metabolism*; D058087:Haptophyta / Q000254:growth & development / Q000502:physiology*
chemical_list: D002245:Carbon Dioxide