CENTER for DARK ENERGY BIOSPHERE INVESTIGATIONS
Menu
  • About
    • Introduction
    • People
    • Spotlight
    • Ethics Policy
    • Data Access & Policy
    • Executive Documents
    • C-DEBI Branded Resources
    • Support C-DEBI
    • Contact Us
  • Research
    • Overview
    • Research Themes
    • Field Sites
    • Facilities, Equipment & Technology
    • Research Support
      • Research Grants
      • Graduate Fellowships
      • Postdoctoral Fellowships
      • Research Exchanges
      • Community Workshops
      • Funded Projects
  • Education
    • Overview
    • For Teachers
    • For High School Students
    • For Undergraduates
      • Overview
      • GEM Summer Course
      • C4 Research Experience
      • CC-RISE Research Internship
      • GGURE Research Experience
      • Partnering Organizations
    • For Graduates & Postdocs
    • For Everyone
    • Education Grants
  • Resources
    • Peer-Reviewed Publications
    • Project Data
    • Protocols
    • Subseafloor Cultures Database
    • Videos
    • Mailing List & Newsletter
    • Meetings & Workshops
    • Networked Speaker Series
    • Professional Development Webinars
    • How to Get Deep Biosphere Samples

Person: A. Szynkiewicz

Order
Date Desc
Date Asc
Title Asc
Title Desc
Publications > Journal Article
Published: May 10, 2019
Applied and Environmental Microbiology
Complex microbial communities drive iron and sulfur cycling in Arctic fjord sediments
Authors: Joy Buongiorno, L. C. Herbert, Laura M. Wehrmann, Alexander B. Michaud, K. Laufer, Hans Røy, Bo Barker Jørgensen, A. Szynkiewicz, A. Faiia, K. M. Yeager, K. Schindler, Karen G. Lloyd
C-DEBI Contribution Number: 476
Publications > Journal Article
Applied and Environmental Microbiology
Complex microbial communities drive iron and sulfur cycling in Arctic fjord sediments
Authors: Joy Buongiorno, L. C. Herbert, Laura M. Wehrmann, Alexander B. Michaud, K. Laufer, Hans Røy, Bo Barker Jørgensen, A. Szynkiewicz, A. Faiia, K. M. Yeager, K. Schindler, Karen G. Lloyd
Published: May 10, 2019
C-DEBI Contribution Number: 476

Abstract

Glacial retreat is changing biogeochemical cycling in the Arctic, where glacial runoff contributes iron for oceanic shelf primary production. In Svalbard fjords, we hypothesize that microbes catalyze intense iron and sulfur cycling in low organic matter sediments. This is because low organic matter limits sulfide generation, allowing iron mobility to the water column instead of precipitation as iron monosulfides. Here, we tested this with high-depth-resolution 16S rRNA gene libraries in the upper 20 cm at two sites in Van Keulenfjorden, Svalbard. At the site closer to the glaciers, iron-reducing Desulfuromonadales, iron-oxidizing Gallionella and Mariprofundus, and sulfur-oxidizing Thiotrichales and Epsilonproteobacteria were abundant above 12 cm depth. Below this depth, the relative abundances of sequences for sulfate-reducing Desulfobacteraceae and Desulfobulbaceae increased. At the outer station, the switch from iron-cycling clades to sulfate reducers occurred at shallower depths (∼5 cm), corresponding to higher sulfate reduction rates. Relatively labile organic matter (shown by δ13C and C/N ratios) was more abundant at this outer site and ordination analysis suggested that this affected microbial community structure in surface sediments. Network analysis revealed more correlations between predicted iron- and sulfur-cycling taxa, and with uncultured clades proximal to the glacier. Together, these results suggest that complex microbial communities catalyze redox cycling of iron and sulfur, especially closer to the glacier, where sulfate reduction is limited due to low organic matter availability. Diminished sulfate reduction in upper sediments enables iron to flux into the overlying water, where it may be transported to the shelf.
Source: http://dx.doi.org/10.1128/aem.00949-19

About C-DEBI  |  Our Research  |  Education & Outreach  |  Resources  |
Contact Us  |  Join Our Mailing List  |  Find Us On Facebook  |  Follow us on Twitter
© 2009-2019 Center for Dark Energy Biosphere Investigations (C-DEBI)

SUPPORT C-DEBI TODAY |  National Science Foundation