English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
 
 
DownloadE-Mail
  Post-glacial microbialite formation in coral reefs of the Pacific, Atlantic, and Indian Oceans

Heindel, K., Birgel, D., Brunner, B., Thiel, V., Westphal, H., Gischler, E., et al. (2012). Post-glacial microbialite formation in coral reefs of the Pacific, Atlantic, and Indian Oceans. Chemical Geology, 304, 117-130.

Item is

Files

show Files
hide Files
:
Brunner12.pdf (Publisher version), 2MB
 
File Permalink:
-
Name:
Brunner12.pdf
Description:
-
OA-Status:
Visibility:
Restricted ( Max Planck Society (every institute); )
MIME-Type / Checksum:
application/pdf
Technical Metadata:
Copyright Date:
-
Copyright Info:
-
License:
-

Locators

show

Creators

show
hide
 Creators:
Heindel, K., Author
Birgel, D., Author
Brunner, B.1, Author           
Thiel, V., Author
Westphal, H., Author
Gischler, E., Author
Ziegenbalg, S. B., Author
Cabioch, G., Author
Sjovall, P., Author
Peckmann, J., Author
Affiliations:
1Department of Biogeochemistry, Max Planck Institute for Marine Microbiology, Max Planck Society, ou_2481693              

Content

show
hide
Free keywords: -
 Abstract: The occurrence of microbialites in post-glacial coral reefs has been interpreted to reflect an ecosystem response to environmental change. The greater thickness of microbialites in reefs with a volcanic hinterland compared to thinner microbial crusts in reefs with a non-volcanic hinterland led to the suggestion that fertilization of the reefal environment by chemical weathering of volcanic rocks stimulated primary productivity and microbialite formation. Using a molecular and isotopic approach on reef-microbialites from Tahiti (Pacific Ocean), it was recently shown that sulfate-reducing bacteria favored the formation of microbial carbonates. To test if similar mechanisms induced microbialite formation in other reefs as well, the Tahitian microbialites are compared with similar microbialites from coral reefs off Vanuatu (Pacific Ocean), Belize (Caribbean Sea, Atlantic Ocean), and the Maldives (Indian Ocean) in this study. The selected study sites cover a wide range of geological settings, reflecting variable input and composition of detritus. The new lipid biomarker data and stable sulfur isotope results confirm that sulfate-reducing bacteria played an intrinsic role in the precipitation of microbial carbonate at all study sites, irrespective of the geological setting. Abundant biomarkers indicative of sulfate reducers include a variety of terminally-branched and mid chain-branched fatty acids as well as mono-O-alkyl glycerol ethers. Isotope evidence for bacterial sulfate reduction is represented by low δ34S values of pyrite (− 43 to − 42‰) enclosed in the microbialites and, compared to seawater sulfate, slightly elevated δ34S and δ18O values of carbonate-associated sulfate (21.9 to 22.2‰ and 11.3 to 12.4‰, respectively). Microbialite formation took place in anoxic micro-environments, which presumably developed through the fertilization of the reef environment and the resultant accumulation of organic matter including bacterial extracellular polymeric substances (EPS), coral mucus, and marine snow in cavities within the coral framework. ToF-SIMS analysis reveals that the dark layers of laminated microbialites are enriched in carbohydrates, which are common constituents of EPS and coral mucus. These results support the hypothesis that bacterial degradation of EPS and coral mucus within microbial mats favored carbonate precipitation. Because reefal microbialites formed by similar processes in very different geological settings, this comparative study suggests that a volcanic hinterland is not required for microbialite growth. Yet, detrital input derived from the weathering of volcanic rocks appears to be a natural fertilizer, being conductive for the growth of microbial mats, which fosters the development of particularly abundant and thick microbial crusts.

Details

show
hide
Language(s): eng - English
 Dates: 2012-04-18
 Publication Status: Issued
 Pages: 14
 Publishing info: -
 Table of Contents: -
 Rev. Type: Peer
 Identifiers: eDoc: 634699
ISI: 000303098900011
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Chemical Geology
  Other : Chem. Geol.
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: Amsterdam : Elsevier
Pages: - Volume / Issue: 304 Sequence Number: - Start / End Page: 117 - 130 Identifier: ISSN: 0009-2541
CoNE: https://pure.mpg.de/cone/journals/resource/954925389240