eCite Digital Repository

Seasonal dynamics in diatom and particulate export fluxes to the deep sea in the Australian sector of the southern Antarctic Zone


Rigual-Hernandez, AS and Trull, TW and Bray, SG and Closset, I and Armand, LK, Seasonal dynamics in diatom and particulate export fluxes to the deep sea in the Australian sector of the southern Antarctic Zone, Journal of Marine Systems, 142 pp. 62-74. ISSN 0924-7963 (2015) [Refereed Article]

Copyright Statement

Copyright 2014 2014 Elsevier B.V.

DOI: doi:10.1016/j.jmarsys.2014.10.002


Particle fluxes were recorded over a one-year period (2001-02) in the southern Antarctic Zone in the Australian Sector of the Southern Ocean. Here, we present the results on the seasonal and vertical variability of biogenic particle and diatom valve fluxes. Total mass and diatom fluxes were highly seasonal, with maxima registered during the austral summer and minima during winter. Biogenic opal dominated sedimentation, followed by carbonate, and very low levels of organic carbon (annual average 1.4%). The strong correlation between opal and organic carbon at both depth levels suggests that a significant fraction of organic matter exported to the deep sea was associated with diatom sedimentation events. Seasonal diatom fluxes appear driven principally by changes in the flux of Fragilariopsis kerguelensis. The occurrence of the sea-ice affiliated diatoms Fragilariopsis cylindrus and Fragilariopsis curta in both sediment traps is considered to correspond to the sedimentation of a diatom bloom advected from an area under the influence of sea ice. Highest fluxes of the subsurface-dwelling species Thalassiothrix antarctica registered at the end of the summer bloom were linked to a drop of the light levels during the summer-autumn transition. This study provides the first annual observation on seasonal succession of diatom species in the Australian sector of the Antarctic Zone, and corresponds, in terms of magnitude and seasonality of diatom fluxes, to those in neighbouring sectors (Pacific and eastern Atlantic).

Item Details

Item Type:Refereed Article
Keywords:diatom flux, particulate flux, sediment traps, Southern Ocean
Research Division:Earth Sciences
Research Group:Oceanography
Research Field:Chemical oceanography
Objective Division:Environmental Management
Objective Group:Management of Antarctic and Southern Ocean environments
Objective Field:Antarctic and Southern Ocean oceanic processes
UTAS Author:Trull, TW (Professor Thomas Trull)
UTAS Author:Bray, SG (Mr Stephen Bray)
ID Code:100339
Year Published:2015
Web of Science® Times Cited:28
Deposited By:CRC-Antarctic Climate & Ecosystems
Deposited On:2015-05-12
Last Modified:2017-11-01

Repository Staff Only: item control page