Photosynthetic impact of hypoxia on in hospite zooxanthellae in the scleractinian coral Pocillopora damicornis

DSpace/Manakin Repository

Search OPUS

Advanced Search


My Account

Show simple item record Ulstrup, KE Hill, R Ralph, PJ 2009-12-21T02:29:53Z 2005-02-02
dc.identifier.citation Marine Ecology Progress Series, 2005, 286 pp. 125 - 132
dc.identifier.issn 0171-8630
dc.identifier.other C1 en_US
dc.description.abstract Shallow water coral reefs may experience hypoxia under conditions of calm weather doldrums. Anaerobic responses of endosymbionts (i.e. zooxanthellae) within Pocillopora damicornis coral colonies were tested using both slow and fast chlorophyll a fluorescence induction kinetics. Zooxanthellae were examined in hospite when exposed to control conditions (26°C, 200 μmol photons m-2 s-1, 100% air-saturation, 4 cm s-1 flow) and to 2 treatments of reduced air content (40 and 0%), achieved by controlling the N2:O2 ratio in water circulating at 2 cm s -1. Furthermore, the impact of water flow on photosynthesis was examined at 0% air saturation by turning off the flow entirely (0 cm s -1), thereby mimicking the environmental conditions of calm weather doldrums. Corals exposed to depleted air content (0 % with and without flow) showed a significant decrease (p < 0.001) in effective quantum yield (φPSII) in comparison with controls. Maximum quantum yield was significantly reduced when gas exchange was inhibited (0% without flow), whereas non-photochemical quenching (NPQ) was not affected. Fast polyphasic fluorescence transients of chlorophyll a fluorescence showed a significant increase in minimum dark-adapted fluorescence, F0, when corals were exposed to anaerobic conditions. Furthermore, an increase in the J peak (2 ms) corresponding to the reduction of the primary electron acceptor, QA, was observed in 0% air-saturation with flow. We found that the most sensitive parameters for detecting physiological change associated with hypoxia were φPSII using slow (pulse-amplitude modulation) fluorescence kinetics, as well as an increase in the O peak, φPo(electron transport efficiency before QA), and an elevation of the J peak on a double-normalised transient using fast (Plant Efficiency Analyser) induction kinetics. © Inter-Research 2005.
dc.language eng
dc.title Photosynthetic impact of hypoxia on in hospite zooxanthellae in the scleractinian coral Pocillopora damicornis
dc.type Journal Article
dc.parent Marine Ecology Progress Series
dc.journal.volume 286
dc.journal.number en_US
dc.publocation Oldendorf Luhe, Germany en_US
dc.identifier.startpage 125 en_US
dc.identifier.endpage 132 en_US DVCRch.Institute for Water & Environmental Resource Mgmnt en_US
dc.conference Verified OK en_US
dc.for 060205 Marine and Estuarine Ecology (Incl. Marine Ichthyology)
dc.personcode 040568
dc.personcode 890085
dc.percentage 100 en_US Marine and Estuarine Ecology (incl. Marine Ichthyology) en_US
dc.classification.type FOR-08 en_US
dc.custom 2.052 en_US
dc.description.keywords fluorescence; fast-induction kinetics; pulse-amplitude modulation; photosystem II; PSII en_US
dc.description.keywords Fast-induction kinetics
dc.description.keywords Fluorescence
dc.description.keywords Photosystem II
dc.description.keywords PSII
dc.description.keywords Pulse-amplitude modulation
pubs.embargo.period Not known
pubs.organisational-group /University of Technology Sydney
pubs.organisational-group /University of Technology Sydney/Faculty of Science
pubs.organisational-group /University of Technology Sydney/Strength - C3
utslib.copyright.status Open Access 2015-04-15 12:23:47.074767+10
utslib.collection.history Uncategorised (ID: 363)
utslib.collection.history General (ID: 2)

Files in this item

This item appears in the following Collection(s)

Show simple item record