Tags

Type your tag names separated by a space and hit enter

Groundwater shapes sediment biogeochemistry and microbial diversity in a submerged Great Lake sinkhole.
Geobiology. 2017 03; 15(2):225-239.G

Abstract

For a large part of earth's history, cyanobacterial mats thrived in low-oxygen conditions, yet our understanding of their ecological functioning is limited. Extant cyanobacterial mats provide windows into the putative functioning of ancient ecosystems, and they continue to mediate biogeochemical transformations and nutrient transport across the sediment-water interface in modern ecosystems. The structure and function of benthic mats are shaped by biogeochemical processes in underlying sediments. A modern cyanobacterial mat system in a submerged sinkhole of Lake Huron (LH) provides a unique opportunity to explore such sediment-mat interactions. In the Middle Island Sinkhole (MIS), seeping groundwater establishes a low-oxygen, sulfidic environment in which a microbial mat dominated by Phormidium and Planktothrix that is capable of both anoxygenic and oxygenic photosynthesis, as well as chemosynthesis, thrives. We explored the coupled microbial community composition and biogeochemical functioning of organic-rich, sulfidic sediments underlying the surface mat. Microbial communities were diverse and vertically stratified to 12 cm sediment depth. In contrast to previous studies, which used low-throughput or shotgun metagenomic approaches, our high-throughput 16S rRNA gene sequencing approach revealed extensive diversity. This diversity was present within microbial groups, including putative sulfate-reducing taxa of Deltaproteobacteria, some of which exhibited differential abundance patterns in the mats and with depth in the underlying sediments. The biological and geochemical conditions in the MIS were distinctly different from those in typical LH sediments of comparable depth. We found evidence for active cycling of sulfur, methane, and nutrients leading to high concentrations of sulfide, ammonium, and phosphorus in sediments underlying cyanobacterial mats. Indicators of nutrient availability were significantly related to MIS microbial community composition, while LH communities were also shaped by indicators of subsurface groundwater influence. These results show that interactions between the mats and sediments are crucial for sustaining this hot spot of biological diversity and biogeochemical cycling.

Authors+Show Affiliations

Department of Biological Sciences, Kent State University, Kent, OH, USA.Department of Biology, Large Lakes Observatory, University of Minnesota Duluth, Duluth, MN, USA.Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI, USA.School of Natural Resources and the Environment, University of Michigan, Ann Arbor, MI, USA.Department of Biological Sciences, Kent State University, Kent, OH, USA.Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI, USA.Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI, USA.Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI, USA.

Pub Type(s)

Journal Article
Research Support, U.S. Gov't, Non-P.H.S.
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

27671809

Citation

Kinsman-Costello, L E., et al. "Groundwater Shapes Sediment Biogeochemistry and Microbial Diversity in a Submerged Great Lake Sinkhole." Geobiology, vol. 15, no. 2, 2017, pp. 225-239.
Kinsman-Costello LE, Sheik CS, Sheldon ND, et al. Groundwater shapes sediment biogeochemistry and microbial diversity in a submerged Great Lake sinkhole. Geobiology. 2017;15(2):225-239.
Kinsman-Costello, L. E., Sheik, C. S., Sheldon, N. D., Allen Burton, G., Costello, D. M., Marcus, D., Uyl, P. A., & Dick, G. J. (2017). Groundwater shapes sediment biogeochemistry and microbial diversity in a submerged Great Lake sinkhole. Geobiology, 15(2), 225-239. https://doi.org/10.1111/gbi.12215
Kinsman-Costello LE, et al. Groundwater Shapes Sediment Biogeochemistry and Microbial Diversity in a Submerged Great Lake Sinkhole. Geobiology. 2017;15(2):225-239. PubMed PMID: 27671809.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Groundwater shapes sediment biogeochemistry and microbial diversity in a submerged Great Lake sinkhole. AU - Kinsman-Costello,L E, AU - Sheik,C S, AU - Sheldon,N D, AU - Allen Burton,G, AU - Costello,D M, AU - Marcus,D, AU - Uyl,P A Den, AU - Dick,G J, Y1 - 2016/09/27/ PY - 2016/01/13/received PY - 2016/08/25/accepted PY - 2016/9/28/pubmed PY - 2017/9/7/medline PY - 2016/9/28/entrez SP - 225 EP - 239 JF - Geobiology JO - Geobiology VL - 15 IS - 2 N2 - For a large part of earth's history, cyanobacterial mats thrived in low-oxygen conditions, yet our understanding of their ecological functioning is limited. Extant cyanobacterial mats provide windows into the putative functioning of ancient ecosystems, and they continue to mediate biogeochemical transformations and nutrient transport across the sediment-water interface in modern ecosystems. The structure and function of benthic mats are shaped by biogeochemical processes in underlying sediments. A modern cyanobacterial mat system in a submerged sinkhole of Lake Huron (LH) provides a unique opportunity to explore such sediment-mat interactions. In the Middle Island Sinkhole (MIS), seeping groundwater establishes a low-oxygen, sulfidic environment in which a microbial mat dominated by Phormidium and Planktothrix that is capable of both anoxygenic and oxygenic photosynthesis, as well as chemosynthesis, thrives. We explored the coupled microbial community composition and biogeochemical functioning of organic-rich, sulfidic sediments underlying the surface mat. Microbial communities were diverse and vertically stratified to 12 cm sediment depth. In contrast to previous studies, which used low-throughput or shotgun metagenomic approaches, our high-throughput 16S rRNA gene sequencing approach revealed extensive diversity. This diversity was present within microbial groups, including putative sulfate-reducing taxa of Deltaproteobacteria, some of which exhibited differential abundance patterns in the mats and with depth in the underlying sediments. The biological and geochemical conditions in the MIS were distinctly different from those in typical LH sediments of comparable depth. We found evidence for active cycling of sulfur, methane, and nutrients leading to high concentrations of sulfide, ammonium, and phosphorus in sediments underlying cyanobacterial mats. Indicators of nutrient availability were significantly related to MIS microbial community composition, while LH communities were also shaped by indicators of subsurface groundwater influence. These results show that interactions between the mats and sediments are crucial for sustaining this hot spot of biological diversity and biogeochemical cycling. SN - 1472-4669 UR - https://www.unboundmedicine.com/medline/citation/27671809/Groundwater_shapes_sediment_biogeochemistry_and_microbial_diversity_in_a_submerged_Great_Lake_sinkhole_ L2 - https://doi.org/10.1111/gbi.12215 DB - PRIME DP - Unbound Medicine ER -