University of Tasmania
Browse

File(s) under permanent embargo

Effect of temperature on the photosynthetic efficiency and morphotype of Phaeocystis antarctica

journal contribution
posted on 2023-05-17, 12:59 authored by Fraser KennedyFraser Kennedy, Andrew McMinnAndrew McMinn, Martin, A

One of the only non-diatom species to dominate sea-ice assemblages is the haptophyte Phaeocystis antarctica. Here, the photosynthetic efficiency and morphotype expression of P. antarctica in response to freezing and melting in an artificial sea-ice habitat is investigated. Maximum quantum yield of photosystem II (Fv/Fm) was significantly different with respect to both light (light and dark, Two-way ANOVA, pb0.001) and depth within the ice (Two-way ANOVA, pb0.001). There was a decline in maximum quantum yield (Fv/ Fm) in cells at each level within the ice, but the decline was greater in the coldest part of the ice (i.e. close to the surface) than at the ice/water interface. Following the initiation of a melt cycle, Fv/Fm increased in both treatments, from 0.48±0.05 to 0.57±0.05 on day 10, and 0.38±0.06 to 0.44±0.07 on day 10, in the light and dark treatments respectively. The ice matrix induced solitary cell formation while melting induced colony formation. This change in morphology is not thought to reflect either temperature or nutrients but the physical presence of ice acting as a trigger for morphological change.

This study utilised a novel ice tank technology to replicate sea-ice habitat and document the response of P. antarctica to freeze/thaw dynamics.

Funding

Australian Research Council

History

Publication title

Journal of Experimental Marine Biology and Ecology

Volume

429

Pagination

7-14

ISSN

0022-0981

Department/School

Institute for Marine and Antarctic Studies

Publisher

Elsevier Science Bv

Place of publication

Po Box 211, Amsterdam, Netherlands, 1000 Ae

Rights statement

Copyright 2012 Elsevier B.V.

Repository Status

  • Restricted

Socio-economic Objectives

Biodiversity in Antarctic and Southern Ocean environments

Usage metrics

    University Of Tasmania

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC