Journal cover Journal topic
Biogeosciences An interactive open-access journal of the European Geosciences Union
https://doi.org/10.5194/bg-2017-180
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
Research article
23 May 2017
Review status
This discussion paper is a preprint. A revision of this manuscript was accepted for the journal Biogeosciences (BG) and is expected to appear here in due course.
Anatomical structure overrides temperature controls on magnesium uptake -- calcification in the Arctic/subarctic coralline algae Leptophytum laeve and Kvaleya epilaeve (Rhodophyta; Corallinales)
Merinda C. Nash and Walter Adey Department of Botany, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA, 20560
Abstract. Calcified coralline red algae are ecologically key organisms in photic benthic environments. In recent decades they have become important climate proxies, especially in the Arctic and Subarctic. It has been widely accepted that Magnesium content in coralline tissues is directly a function of ambient temperature, and this is a primary basis for their value as a climate archive. In this paper we show for two genera of Arctic/Subarctic corallines, Leptophytum laeve and Kvaleya epilaeve, that previously unrecognized complex tissue and cell wall anatomy bears a variety of basal signatures for Mg content, with the accepted temperature relationship being secondary. The interfilament carbonate has lower Mg than adjacent cell walls and the hypothallial cell walls have the highest Mg content. The internal structure of the hypothallial cell walls can differ substantially from the perithallial radial cell wall structure. Using high-magnification Scanning Electron Microscopy and etching we expose the nm-scale structures within the cell walls and interfilament. Fibrils concentrate at the internal and external edges of the cell walls. Fibrils ~ 10 nm thick appear to thread through the radial Mg-calcite grains and form concentric bands within the cell wall. This banding may control Mg distribution within the cell. Similar fibril banding is present in the hypothallial cell walls but not the interfilament. Climate archiving with corallines can achieve greater precision with recognition of these parameters. This paper is part of a series of investigations on controls on Mg uptake and distribution within the crusts of a range of coralline genera.

Citation: Nash, M. C. and Adey, W.: Anatomical structure overrides temperature controls on magnesium uptake -- calcification in the Arctic/subarctic coralline algae Leptophytum laeve and Kvaleya epilaeve (Rhodophyta; Corallinales), Biogeosciences Discuss., https://doi.org/10.5194/bg-2017-180, in review, 2017.
Merinda C. Nash and Walter Adey
Interactive discussionStatus: closed
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Printer-friendly Version - Printer-friendly version      Supplement - Supplement
 
RC1: 'referee comment', Jan Fietzke, 19 Jun 2017 Printer-friendly Version 
AC1: 'Response to reviewers comments', Merinda Nash, 13 Aug 2017 Printer-friendly Version Supplement 
 
RC2: 'revision of bg-2017-180 MS', Annalisa Caragnano, 05 Jul 2017 Printer-friendly Version 
 
AC2: 'Revised MS', Merinda Nash, 13 Aug 2017 Printer-friendly Version Supplement 
 
EC1: 'assessment bg-2017-180 by Editor', Lennart de Nooijer, 04 Sep 2017 Printer-friendly Version 
Merinda C. Nash and Walter Adey
Merinda C. Nash and Walter Adey

Viewed

Total article views: 281 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
215 50 16 281 1 16

Views and downloads (calculated since 23 May 2017)

Cumulative views and downloads (calculated since 23 May 2017)

Viewed (geographical distribution)

Total article views: 281 (including HTML, PDF, and XML)

Thereof 281 with geography defined and 0 with unknown origin.

Country # Views %
  • 1

Saved

Discussed

Latest update: 17 Nov 2017
Publications Copernicus
Download
Short summary
Past seawater temperatures can be reconstructed using magnesium / calcium ratios of biogenic carbonates. As temperature increases, so does magnesium. Here we show that for these arctic/subarctic coralline algae, anatomy is the first control on Mg / Ca, not temperature. When using coralline algae for temperature reconstruction, it is first necessary to check for anatomical influences on Mg / Ca.
Past seawater temperatures can be reconstructed using magnesium / calcium ratios of biogenic...
Share