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Clare MA, Lichtschlag A, Paradis S, Barlow NLM. Assessing the impact of the global subsea telecommunications network on sedimentary organic carbon stocks. Nat Commun 2023; 14:2080. [PMID: 37045871 PMCID: PMC10097694 DOI: 10.1038/s41467-023-37854-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 03/28/2023] [Indexed: 04/14/2023] Open
Abstract
The sequestration of organic carbon in seafloor sediments plays a key role in regulating global climate; however, human activities can disturb previously-sequestered carbon stocks, potentially reducing the capacity of the ocean to store CO2. Recent studies revealed profound seafloor impacts and sedimentary carbon loss due to fishing and shipping, yet most other human activities in the ocean have been overlooked. Here, we present an assessment of organic carbon disturbance related to the globally-extensive subsea telecommunications cable network. Up to 2.82-11.26 Mt of organic carbon worldwide has been disturbed as a result of cable burial, in water depths of up to 2000 m. While orders of magnitude lower than that disturbed by bottom fishing, it is a non-trivial amount that is absent from global budgets. Future offshore developments that disturb the seafloor should consider the safeguarding of carbon stocks, across the full spectrum of Blue Economy industries.
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Affiliation(s)
- M A Clare
- Ocean Biogeoscience Research Group, National Oceanography Centre, Southampton, UK.
| | - A Lichtschlag
- Ocean Biogeoscience Research Group, National Oceanography Centre, Southampton, UK
| | - S Paradis
- Geological Institute, ETH Zürich, Zürich, Switzerland
| | - N L M Barlow
- School of Earth and Environment, University of Leeds, Leeds, UK
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2
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Gomez-Saez GV, Dittmar T, Holtappels M, Pohlabeln AM, Lichtschlag A, Schnetger B, Boetius A, Niggemann J. Sulfurization of dissolved organic matter in the anoxic water column of the Black Sea. Sci Adv 2021; 7:7/25/eabf6199. [PMID: 34134989 PMCID: PMC8208715 DOI: 10.1126/sciadv.abf6199] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 05/04/2021] [Indexed: 05/05/2023]
Abstract
Today's oceans store as much dissolved organic carbon (DOC) in the water column as there is CO2 in the atmosphere, and as such dissolved organic matter (DOM) is an important component of the global carbon cycle. It was shown that in anoxic marine sediments, reduced sulfur species (e.g., H2S) abiotically react with organic matter, contributing to carbon preservation. It is not known whether such processes also contribute to preserving DOM in ocean waters. Here, we show DOM sulfurization within the sulfidic waters of the Black Sea, by combining elemental, isotopic, and molecular analyses. Dissolved organic sulfur (DOS) is formed largely in the water column and not derived from sediments or allochthonous nonmarine sources. Our findings suggest that during large-scale anoxic events, DOM may accumulate through abiotic reactions with reduced sulfur species, having long-lasting effects on global climate by enhancing organic carbon sequestration.
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Affiliation(s)
- Gonzalo V Gomez-Saez
- Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg, Oldenburg, Germany.
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Sciences (AWI), Bremerhaven, Germany
| | - Thorsten Dittmar
- Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg, Oldenburg, Germany
- Helmholtz Institute for Functional Marine Biodiversity (HIFMB), University of Oldenburg, Oldenburg, Germany
| | - Moritz Holtappels
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Sciences (AWI), Bremerhaven, Germany
- Max Planck Institute for Marine Microbiology (MPI), Bremen, Germany
- MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Anika M Pohlabeln
- Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg, Oldenburg, Germany
| | - Anna Lichtschlag
- Max Planck Institute for Marine Microbiology (MPI), Bremen, Germany
- National Oceanography Centre, Southampton, UK
| | - Bernhard Schnetger
- Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg, Oldenburg, Germany
| | - Antje Boetius
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Sciences (AWI), Bremerhaven, Germany
- Max Planck Institute for Marine Microbiology (MPI), Bremen, Germany
- MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Jutta Niggemann
- Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg, Oldenburg, Germany
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3
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Meister P, Wiedling J, Lott C, Bach W, Kuhfuß H, Wegener G, Böttcher ME, Deusner C, Lichtschlag A, Bernasconi SM, Weber M. Anaerobic methane oxidation inducing carbonate precipitation at abiogenic methane seeps in the Tuscan archipelago (Italy). PLoS One 2018; 13:e0207305. [PMID: 30566474 PMCID: PMC6300204 DOI: 10.1371/journal.pone.0207305] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Accepted: 10/29/2018] [Indexed: 11/21/2022] Open
Abstract
Seepage of methane (CH4) on land and in the sea may significantly affect Earth's biogeochemical cycles. However processes of CH4 generation and consumption, both abiotic and microbial, are not always clear. We provide new geochemical and isotope data to evaluate if a recently discovered CH4 seepage from the shallow seafloor close to the Island of Elba (Tuscany) and two small islands nearby are derived from abiogenic or biogenic sources and whether carbonate encrusted vents are the result of microbial or abiotic processes. Emission of gas bubbles (predominantly CH4) from unlithified sands was observed at seven spots in an area of 100 m2 at Pomonte (Island of Elba), with a total rate of 234 ml m-2 d-1. The measured carbon isotope values of CH4 of around -18‰ (VPDB) in combination with the measured δ2H value of -120‰ (VSMOW) and the inverse correlation of δ13C-value with carbon number of hydrocarbon gases are characteristic for sites of CH4 formation through abiogenic processes, specifically abiogenic formation of CH4 via reduction of CO2 by H2. The H2 for methanogenesis likely derives from ophiolitic host rock within the Ligurian accretionary prism. The lack of hydrothermal activity allows CH4 gas to become decoupled from the stagnant aqueous phase. Hence no hyperalkaline fluid is currently released at the vent sites. Within the seep area a decrease in porewater sulphate concentrations by ca. 5 mmol/l relative to seawater and a concomitant increase in sulphide and dissolved inorganic carbon (DIC) indicate substantial activity of sulphate-dependent anaerobic oxidation of methane (AOM). In absence of any other dissimilatory pathway, the δ13C-values between -17 and -5‰ in dissolved inorganic carbon and aragonite cements suggest that the inorganic carbon is largely derived from CH4. The formation of seep carbonates is thus microbially induced via anaerobic oxidation of abiotic CH4.
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Affiliation(s)
- Patrick Meister
- Department of Geodynamics and Sedimentology, University of Vienna, Vienna, Austria
| | - Johanna Wiedling
- HYDRA Marine Sciences GmbH, Sinzheim, Germany and HYDRA Field Station Elba, Italy
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Christian Lott
- HYDRA Marine Sciences GmbH, Sinzheim, Germany and HYDRA Field Station Elba, Italy
| | - Wolfgang Bach
- MARUM–Center for Marine Environmental Research, University of Bremen, Bremen, Germany
| | - Hanna Kuhfuß
- HYDRA Marine Sciences GmbH, Sinzheim, Germany and HYDRA Field Station Elba, Italy
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Gunter Wegener
- Max Planck Institute for Marine Microbiology, Bremen, Germany
- MARUM–Center for Marine Environmental Research, University of Bremen, Bremen, Germany
| | - Michael E. Böttcher
- Geochemistry & Isotope Biogeochemistry Group, Leibniz Institute for Baltic Sea Research (IOW), Warnemünde, Germany
| | | | - Anna Lichtschlag
- National Oceanography Centre, University of Southampton Water Front Campus, Southampton, United Kingdom
| | | | - Miriam Weber
- HYDRA Marine Sciences GmbH, Sinzheim, Germany and HYDRA Field Station Elba, Italy
- Max Planck Institute for Marine Microbiology, Bremen, Germany
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Klar JK, Homoky WB, Statham PJ, Birchill AJ, Harris EL, Woodward EMS, Silburn B, Cooper MJ, James RH, Connelly DP, Chever F, Lichtschlag A, Graves C. Stability of dissolved and soluble Fe(II) in shelf sediment pore waters and release to an oxic water column. Biogeochemistry 2017; 135:49-67. [PMID: 32009691 PMCID: PMC6961528 DOI: 10.1007/s10533-017-0309-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 02/06/2017] [Indexed: 05/28/2023]
Abstract
Shelf sediments underlying temperate and oxic waters of the Celtic Sea (NW European Shelf) were found to have shallow oxygen penetrations depths from late spring to late summer (2.2-5.8 mm below seafloor) with the shallowest during/after the spring-bloom (mid-April to mid-May) when the organic carbon content was highest. Sediment porewater dissolved iron (dFe, <0.15 µm) mainly (>85%) consisted of Fe(II) and gradually increased from 0.4 to 15 μM at the sediment surface to ~100-170 µM at about 6 cm depth. During the late spring this Fe(II) was found to be mainly present as soluble Fe(II) (>85% sFe, <0.02 µm). Sub-surface dFe(II) maxima were enriched in light isotopes (δ56Fe -2.0 to -1.5‰), which is attributed to dissimilatory iron reduction (DIR) during the bacterial decomposition of organic matter. As porewater Fe(II) was oxidised to insoluble Fe(III) in the surface sediment layer, residual Fe(II) was further enriched in light isotopes (down to -3.0‰). Ferrozine-reactive Fe(II) was found in surface porewaters and in overlying core top waters, and was highest in the late spring period. Shipboard experiments showed that depletion of bottom water oxygen in late spring can lead to a substantial release of Fe(II). Reoxygenation of bottom water caused this Fe(II) to be rapidly lost from solution, but residual dFe(II) and dFe(III) remained (12 and 33 nM) after >7 h. Iron(II) oxidation experiments in core top and bottom waters also showed removal from solution but at rates up to 5-times slower than predicted from theoretical reaction kinetics. These data imply the presence of ligands capable of complexing Fe(II) and supressing oxidation. The lower oxidation rate allows more time for the diffusion of Fe(II) from the sediments into the overlying water column. Modelling indicates significant diffusive fluxes of Fe(II) (on the order of 23-31 µmol m-2 day-1) are possible during late spring when oxygen penetration depths are shallow, and pore water Fe(II) concentrations are highest. In the water column this stabilised Fe(II) will gradually be oxidised and become part of the dFe(III) pool. Thus oxic continental shelves can supply dFe to the water column, which is enhanced during a small period of the year after phytoplankton bloom events when organic matter is transferred to the seafloor. This input is based on conservative assumptions for solute exchange (diffusion-reaction), whereas (bio)physical advection and resuspension events are likely to accelerate these solute exchanges in shelf-seas.
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Affiliation(s)
- J. K. Klar
- Ocean and Earth Science, National Oceanography Centre, University of Southampton, Southampton, SO14 3ZH UK
- Present Address: LEGOS, Université de Toulouse, CNES, CNRS, IRD, UPS, 14 Avenue Edouard Belin, 31400 Toulouse, France
| | - W. B. Homoky
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, OX1 3AN UK
| | - P. J. Statham
- Ocean and Earth Science, National Oceanography Centre, University of Southampton, Southampton, SO14 3ZH UK
| | - A. J. Birchill
- School of Geography, Earth and Environmental Science, University of Plymouth, Drake Circus, Plymouth, PL4 8AA UK
| | - E. L. Harris
- Ocean and Earth Science, National Oceanography Centre, University of Southampton, Southampton, SO14 3ZH UK
| | - E. M. S. Woodward
- Plymouth Marine Laboratory, Prospect Place, The Hoe, Plymouth, PL1 3DH UK
| | - B. Silburn
- Centre for Environment, Fisheries and Aquaculture Science, Pakefield Road, Lowestoft, NR33 0HT UK
| | - M. J. Cooper
- Ocean and Earth Science, National Oceanography Centre, University of Southampton, Southampton, SO14 3ZH UK
| | - R. H. James
- Ocean and Earth Science, National Oceanography Centre, University of Southampton, Southampton, SO14 3ZH UK
| | - D. P. Connelly
- Marine Geosciences, National Oceanography Centre, European Way, Southampton, SO14 3ZH UK
| | - F. Chever
- Ocean and Earth Science, National Oceanography Centre, University of Southampton, Southampton, SO14 3ZH UK
| | - A. Lichtschlag
- Marine Geosciences, National Oceanography Centre, European Way, Southampton, SO14 3ZH UK
| | - C. Graves
- Ocean and Earth Science, National Oceanography Centre, University of Southampton, Southampton, SO14 3ZH UK
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Jessen GL, Lichtschlag A, Ramette A, Pantoja S, Rossel PE, Schubert CJ, Struck U, Boetius A. Hypoxia causes preservation of labile organic matter and changes seafloor microbial community composition (Black Sea). Sci Adv 2017; 3:e1601897. [PMID: 28246637 PMCID: PMC5302875 DOI: 10.1126/sciadv.1601897] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 01/04/2017] [Indexed: 05/13/2023]
Abstract
Bottom-water oxygen supply is a key factor governing the biogeochemistry and community composition of marine sediments. Whether it also determines carbon burial rates remains controversial. We investigated the effect of varying oxygen concentrations (170 to 0 μM O2) on microbial remineralization of organic matter in seafloor sediments and on community diversity of the northwestern Crimean shelf break. This study shows that 50% more organic matter is preserved in surface sediments exposed to hypoxia compared to oxic bottom waters. Hypoxic conditions inhibit bioturbation and decreased remineralization rates even within short periods of a few days. These conditions led to the accumulation of threefold more phytodetritus pigments within 40 years compared to the oxic zone. Bacterial community structure also differed between oxic, hypoxic, and anoxic zones. Functional groups relevant in the degradation of particulate organic matter, such as Flavobacteriia, Gammaproteobacteria, and Deltaproteobacteria, changed with decreasing oxygenation, and the microbial community of the hypoxic zone took longer to degrade similar amounts of deposited reactive matter. We conclude that hypoxic bottom-water conditions-even on short time scales-substantially increase the preservation potential of organic matter because of the negative effects on benthic fauna and particle mixing and by favoring anaerobic processes, including sulfurization of matter.
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Affiliation(s)
- Gerdhard L Jessen
- Max Planck Institute for Marine Microbiology, Bremen, Germany.; HGF MPG Joint Research Group for Deep-Sea Ecology and Technology, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Sciences, Bremerhaven, Germany
| | - Anna Lichtschlag
- Max Planck Institute for Marine Microbiology, Bremen, Germany.; HGF MPG Joint Research Group for Deep-Sea Ecology and Technology, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Sciences, Bremerhaven, Germany
| | - Alban Ramette
- Max Planck Institute for Marine Microbiology, Bremen, Germany.; HGF MPG Joint Research Group for Deep-Sea Ecology and Technology, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Sciences, Bremerhaven, Germany
| | - Silvio Pantoja
- Department of Oceanography and COPAS Sur-Austral, University of Concepción, Concepción, Chile
| | - Pamela E Rossel
- Max Planck Institute for Marine Microbiology, Bremen, Germany.; HGF MPG Joint Research Group for Deep-Sea Ecology and Technology, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Sciences, Bremerhaven, Germany.; Research Group for Marine Geochemistry (ICBM-MPI Bridging Group), Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg, Oldenburg, Germany
| | - Carsten J Schubert
- Department of Surface Waters-Research and Management, Swiss Federal Institute of Aquatic Science and Technology, Kastanienbaum, Switzerland
| | - Ulrich Struck
- Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Berlin, Germany
| | - Antje Boetius
- Max Planck Institute for Marine Microbiology, Bremen, Germany.; HGF MPG Joint Research Group for Deep-Sea Ecology and Technology, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Sciences, Bremerhaven, Germany
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Jessen GL, Lichtschlag A, Struck U, Boetius A. Distribution and Composition of Thiotrophic Mats in the Hypoxic Zone of the Black Sea (150-170 m Water Depth, Crimea Margin). Front Microbiol 2016; 7:1011. [PMID: 27446049 PMCID: PMC4925705 DOI: 10.3389/fmicb.2016.01011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 06/14/2016] [Indexed: 01/28/2023] Open
Abstract
At the Black Sea chemocline, oxygen- and sulfide-rich waters meet and form a niche for thiotrophic pelagic bacteria. Here we investigated an area of the Northwestern Black Sea off Crimea close to the shelf break, where the chemocline reaches the seafloor at around 150-170 m water depth, to assess whether thiotrophic bacteria are favored in this zone. Seafloor video transects were carried out with the submersible JAGO covering 20 km(2) on the region between 110 and 200 m depth. Around the chemocline we observed irregular seafloor depressions, covered with whitish mats of large filamentous bacteria. These comprised 25-55% of the seafloor, forming a belt of 3 km width around the chemocline. Cores from the mats obtained with JAGO showed higher accumulations of organic matter under the mats compared to mat-free sediments. The mat-forming bacteria were related to Beggiatoa-like large filamentous sulfur bacteria based on 16S rRNA sequences from the mat, and visual characteristics. The microbial community under the mats was significantly different from the surrounding sediments and enriched with taxa affiliated with polymer degrading, fermenting and sulfate reducing microorganisms. Under the mats, higher organic matter accumulation, as well as higher remineralization and radiotracer-based sulfate reduction rates were measured compared to outside the mat. Mat-covered and mat-free sediments showed similar degradability of the bulk organic matter pool, suggesting that the higher sulfide fluxes and subsequent development of the thiotrophic mats in the patches are consequences of the accumulation of organic matter rather than its qualitative composition. Our observations suggest that the key factors for the distribution of thiotrophic mat-forming communities near to the Crimean shelf break are hypoxic conditions that (i) repress grazers, (ii) enhance the accumulation and degradation of labile organic matter by sulfate-reducers, and (iii) favor thiotrophic filamentous bacteria which are adapted to exploit steep gradients in oxygen and sulfide availability; in addition to a specific seafloor topography which may relate to internal waves at the shelf break.
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Affiliation(s)
- Gerdhard L Jessen
- HGF-MPG Group for Deep Sea Ecology and Technology, Max Planck Institute for Marine Microbiology Bremen, Germany
| | - Anna Lichtschlag
- HGF-MPG Group for Deep Sea Ecology and Technology, Max Planck Institute for Marine Microbiology Bremen, Germany
| | - Ulrich Struck
- Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung Berlin, Germany
| | - Antje Boetius
- HGF-MPG Group for Deep Sea Ecology and Technology, Max Planck Institute for Marine MicrobiologyBremen, Germany; Alfred Wegener Institute, Helmholtz Center for Polar and Marine ResearchBremerhaven, Germany
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Hassenrück C, Fink A, Lichtschlag A, Tegetmeyer HE, de Beer D, Ramette A. Quantification of the effects of ocean acidification on sediment microbial communities in the environment: the importance of ecosystem approaches. FEMS Microbiol Ecol 2016; 92:fiw027. [PMID: 26887661 PMCID: PMC4828923 DOI: 10.1093/femsec/fiw027] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 10/31/2015] [Accepted: 02/08/2016] [Indexed: 12/14/2022] Open
Abstract
To understand how ocean acidification (OA) influences sediment microbial communities, naturally CO2-rich sites are increasingly being used as OA analogues. However, the characterization of these naturally CO2-rich sites is often limited to OA-related variables, neglecting additional environmental variables that may confound OA effects. Here, we used an extensive array of sediment and bottom water parameters to evaluate pH effects on sediment microbial communities at hydrothermal CO2 seeps in Papua New Guinea. The geochemical composition of the sediment pore water showed variations in the hydrothermal signature at seep sites with comparable pH, allowing the identification of sites that may better represent future OA scenarios. At these sites, we detected a 60% shift in the microbial community composition compared with reference sites, mostly related to increases in Chloroflexi sequences. pH was among the factors significantly, yet not mainly, explaining changes in microbial community composition. pH variation may therefore often not be the primary cause of microbial changes when sampling is done along complex environmental gradients. Thus, we recommend an ecosystem approach when assessing OA effects on sediment microbial communities under natural conditions. This will enable a more reliable quantification of OA effects via a reduction of potential confounding effects.
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Affiliation(s)
- Christiane Hassenrück
- Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359 Bremen, Germany
| | - Artur Fink
- Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359 Bremen, Germany
| | - Anna Lichtschlag
- National Oceanography Centre, University of Southampton Waterfront Campus, European Way, Southampton SO14 3ZH, UK
| | - Halina E Tegetmeyer
- Center for Biotechnology, Bielefeld University, Universitätsstrasse 27, 33615 Bielefeld, Germany
| | - Dirk de Beer
- Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359 Bremen, Germany
| | - Alban Ramette
- Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359 Bremen, Germany Institute of Social and Preventive Medicine, Bern University, Finkenhubelweg 11, 3012 Bern, Switzerland
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Sergeeva NG, Gooday AJ, Mazlumyan SA, Kolesnikova EA, Lichtschlag A, Kosheleva TN, Anikeeva OV. Meiobenthos of the Oxic/Anoxic Interface in the Southwestern Region of the Black Sea: Abundance and Taxonomic Composition. Cellular Origin, Life in Extreme Habitats and Astrobiology 2012. [DOI: 10.1007/978-94-007-1896-8_20] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Grünke S, Felden J, Lichtschlag A, Girnth AC, De Beer D, Wenzhöfer F, Boetius A. Niche differentiation among mat-forming, sulfide-oxidizing bacteria at cold seeps of the Nile Deep Sea Fan (Eastern Mediterranean Sea). Geobiology 2011; 9:330-348. [PMID: 21535364 DOI: 10.1111/j.1472-4669.2011.00281.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Sulfidic muds of cold seeps on the Nile Deep Sea Fan (NDSF) are populated by different types of mat-forming sulfide-oxidizing bacteria. The predominant sulfide oxidizers of three different mats were identified by microscopic and phylogenetic analyses as (i) Arcobacter species producing cotton-ball-like sulfur precipitates, (ii) large filamentous sulfur bacteria including Beggiatoa species, and (iii) single, spherical Thiomargarita species. High resolution in situ microprofiles revealed different geochemical settings selecting for the different mat types. Arcobacter mats occurred where oxygen and sulfide overlapped above the seafloor in the bottom water interface. Filamentous sulfide oxidizers were associated with steep gradients of oxygen and sulfide in the sediment. A dense population of Thiomargarita was favored by temporarily changing supplies of oxygen and sulfide in the bottom water. These results indicate that the decisive factors in selecting for different mat-forming bacteria within one deep-sea province are spatial or temporal variations in energy supply. Furthermore, the occurrence of Arcobacter spp.-related 16S rRNA genes in the sediments below all three types of mats, as well as on top of brine lakes of the NDSF, indicates that this group of sulfide oxidizers can switch between different life modes depending on the geobiochemical habitat setting.
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Affiliation(s)
- S Grünke
- HGF-MPG Joint Research Group on Deep Sea Ecology and Technology, Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany.
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Girnth AC, Grünke S, Lichtschlag A, Felden J, Knittel K, Wenzhöfer F, de Beer D, Boetius A. A novel, mat-forming Thiomargarita population associated with a sulfidic fluid flow from a deep-sea mud volcano. Environ Microbiol 2010; 13:495-505. [DOI: 10.1111/j.1462-2920.2010.02353.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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11
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Grünke S, Lichtschlag A, de Beer D, Kuypers M, Lösekann-Behrens T, Ramette A, Boetius A. Novel observations of Thiobacterium, a sulfur-storing Gammaproteobacterium producing gelatinous mats. ISME J 2010; 4:1031-43. [PMID: 20220790 DOI: 10.1038/ismej.2010.23] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The genus Thiobacterium includes uncultivated rod-shaped microbes containing several spherical grains of elemental sulfur and forming conspicuous gelatinous mats. Owing to the fragility of mats and cells, their 16S ribosomal RNA genes have not been phylogenetically classified. This study examined the occurrence of Thiobacterium mats in three different sulfidic marine habitats: a submerged whale bone, deep-water seafloor and a submarine cave. All three mats contained massive amounts of Thiobacterium cells and were highly enriched in sulfur. Microsensor measurements and other biogeochemistry data suggest chemoautotrophic growth of Thiobacterium. Sulfide and oxygen microprofiles confirmed the dependence of Thiobacterium on hydrogen sulfide as energy source. Fluorescence in situ hybridization indicated that Thiobacterium spp. belong to the Gammaproteobacteria, a class that harbors many mat-forming sulfide-oxidizing bacteria. Further phylogenetic characterization of the mats led to the discovery of an unexpected microbial diversity associated with Thiobacterium.
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Affiliation(s)
- Stefanie Grünke
- HGF-MPG Joint Research Group for Deep Sea Ecology and Technology, Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany.
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