title: The response of marine picoplankton to ocean acidification.
abstract: Since industrialization global CO(2)  emissions have increased, and as a consequence oceanic pH is predicted to drop by 0.3-0.4 units before the end of the century - a process coined 'ocean acidification'. Consequently, there is significant interest in how pH changes will affect the ocean's biota and integral processes. We investigated marine picoplankton (0.2-2 µm diameter) community response to predicted end of century CO(2)  concentrations, via a 'high-CO(2) ' (∼ 750 ppm) large-volume (11 000 l) contained seawater mesocosm approach. We found little evidence of changes occurring in bacterial abundance or community composition due to elevated CO(2)  under both phytoplankton pre-bloom/bloom and post-bloom conditions. In contrast, significant differences were observed between treatments for a number of key picoeukaryote community members. These data suggested a key outcome of ocean acidification is a more rapid exploitation of elevated CO(2)  levels by photosynthetic picoeukaryotes. Thus, our study indicates the need for a more thorough understanding of picoeukaryote-mediated carbon flow within ocean acidification experiments, both in relation to picoplankton carbon sources, sinks and transfer to higher trophic levels.
authors.affiliation: Centre for Ecology and Hydrology, Wallingford, Benson Lane, Crowmarsh Gifford, Wallingford OX108BB, UK.
authors.forename: Lindsay K
authors.initials: LK
authors.lastname: Newbold
authors.forename: Anna E
authors.initials: AE
authors.lastname: Oliver
authors.forename: Tim
authors.initials: T
authors.lastname: Booth
authors.forename: Bela
authors.initials: B
authors.lastname: Tiwari
authors.forename: Todd
authors.initials: T
authors.lastname: Desantis
authors.forename: Michael
authors.initials: M
authors.lastname: Maguire
authors.forename: Gary
authors.initials: G
authors.lastname: Andersen
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: van der Gast
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Whiteley
mesh_terms: D001419:Bacteria / Q000145:classification / Q000235:genetics; D018407:Bacterial Physiological Phenomena; D044822:Biodiversity; D002244:Carbon / Q000378:metabolism; D002245:Carbon Dioxide / Q000737:chemistry; D056890:Eukaryota / Q000502:physiology; D006863:Hydrogen-Ion Concentration; D009792:Oceans and Seas; D010802:Phylogeny; D010839:Phytoplankton / Q000502:physiology; D012623:Seawater / Q000737:chemistry*
chemical_list: D002245:Carbon Dioxide; D002244:Carbon