1
|
Dong C, Chen Q, Chen J, Dong L, Chen Y, Jiao N, Tang K. Investigating organic sulfur in estuarine and offshore environments: A combined field and cultivation approach. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 926:171599. [PMID: 38490410 DOI: 10.1016/j.scitotenv.2024.171599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 03/06/2024] [Accepted: 03/07/2024] [Indexed: 03/17/2024]
Abstract
Estuarine-offshore sediments accumulate substantial particulate organic matter, containing organic sulfur as a key component. However, the distribution and sources of organic sulfur in such environments remain poorly understood. This study investigated organic sulfur in the Yangtze River Estuary and adjacent East China Sea. Dissolved organic sulfur varied from 0.65 to 1.99 μmol/L (molar S:C 0.006-0.018), while particulate organic sulfur ranged from 0.42 to 2.69 μmol/L (molar S:C 0.007-0.082). Sedimentary organic sulfur exhibited a similar molar S:C ratio (0.014-0.071) to particulate organic sulfur in bottom water, implying that particulate matter deposition is a potential source. Furthermore, sediments exposed to frequent hypoxia harbored significantly higher organic sulfur and S:C values compared to non-hypoxic areas. Laboratory incubation experiments revealed the underlying mechanism: sustained activity of sulfate-reducing bacteria in hypoxic sediments led to a substantial increase in sedimentary organic sulfur (from 15 to 53 μmol/g) within 600 days. This microbially driven sulfurization rendered over 90 % of the organic sulfur resistant to acid hydrolysis. Therefore, this study demonstrates that, alongside particle deposition, microbial sulfurization significantly contributes to organic sulfur enrichment and likely promotes organic matter preservation in estuarine-offshore sediments, particularly under hypoxic conditions. This finding advances our understanding of organic sulfur sources in these vital ecosystems.
Collapse
Affiliation(s)
- Changjie Dong
- State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China
| | - Quanrui Chen
- State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China
| | - Junhui Chen
- State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China
| | - Liang Dong
- School of Oceanography, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yaojin Chen
- State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China
| | - Nianzhi Jiao
- State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China.
| | - Kai Tang
- State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China.
| |
Collapse
|
2
|
Brünjes J, Seidel M, Dittmar T, Niggemann J, Schubotz F. Natural Asphalt Seeps Are Potential Sources for Recalcitrant Oceanic Dissolved Organic Sulfur and Dissolved Black Carbon. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:9092-9102. [PMID: 35584055 DOI: 10.1021/acs.est.2c01123] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Natural oil seepages contribute about one-half of the annual petroleum input to marine systems. Yet, environmental implications and the persistence of water-soluble hydrocarbons from these seeps are vastly unknown. We investigated the release of oil-derived dissolved organic matter (DOM) from natural deep sea asphalt seeps using laboratory incubation experiments. Fresh asphalt samples collected at the Chapopote asphalt volcano in the Southern Gulf of Mexico were incubated aerobically in artificial seawater over 4 weeks. The compositional changes in the water-soluble fraction of asphalt-derived DOM were determined with ultrahigh-resolution mass spectrometry (Fourier-transform ion cyclotron resonance mass spectrometry, FT-ICR-MS) and by excitation-emission matrix spectroscopy to characterize fluorescent DOM (FDOM) applying parallel factor (PARAFAC) analysis. Highly reduced aliphatic asphalt-derived DOM was readily biodegraded, while aromatic and sulfur-enriched DOM appeared to be less bioavailable and accumulated in the aqueous phase. A quantitative molecular tracer approach revealed the abundance of highly condensed aromatic molecules of thermogenic origin. Our results indicate that natural asphalt and potentially other petroleum seepages can be sources of recalcitrant dissolved organic sulfur and dissolved black carbon to the ocean.
Collapse
Affiliation(s)
- Jonas Brünjes
- MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen 28359, Germany
| | - Michael Seidel
- Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg 26129, Germany
| | - Thorsten Dittmar
- Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg 26129, Germany
- Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg, Oldenburg 26129, Germany
| | - Jutta Niggemann
- Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg 26129, Germany
| | - Florence Schubotz
- MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen 28359, Germany
| |
Collapse
|
3
|
Gomez-Saez GV, Pohlabeln AM, Stubbins A, Marsay CM, Dittmar T. Photochemical Alteration of Dissolved Organic Sulfur from Sulfidic Porewater. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:14144-14154. [PMID: 29136372 DOI: 10.1021/acs.est.7b03713] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Sulfidic sediments are a source of dissolved organic sulfur (DOS) to the ocean but the fate of sedimentary DOS in the oxic, sunlit water column is unknown. We hypothesized that photodegradation after discharge from the dark sedimentary environment results in DOS molecular transformation and decomposition. To test this hypothesis, sulfidic porewater from a saltmarsh was exposed to potential abiotic transformations of dissolved organic matter (DOM) in the water column. We quantitatively investigated DOM transformations via elemental analysis and molecularly via ultrahigh-resolution mass spectrometry. Our study indicated that photoreactivity is dependent on DOM elemental composition as DOS molecular formulas were more photolabile than those without sulfur. Prior to solar irradiation, of the 6451 identified molecular formulas in sulfidic porewater, 39% contained sulfur. After 29 days of irradiation, the DOS concentration was depleted from 13 to 1 μM, together with a 9% decrease in the number of DOS molecular formulas. Comparing porewater and oceanic DOS molecular formulas, solar irradiation increased the similarity due to the removal of photolabile DOS formulas not present in the ocean. In conclusion, DOS from sulfidic sediments is preferentially photolabile and solar irradiation can be a potential mechanism controlling the stability and fate of porewater DOS.
Collapse
Affiliation(s)
- Gonzalo V Gomez-Saez
- Research Group for Marine Geochemistry (ICBM - MPI Bridging Group), Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg , D-26111 Oldenburg, Germany
| | - Anika M Pohlabeln
- Research Group for Marine Geochemistry (ICBM - MPI Bridging Group), Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg , D-26111 Oldenburg, Germany
| | - Aron Stubbins
- Skidaway Institute of Oceanography, Department of Marine Sciences, University of Georgia , Savannah, Georgia 30602-3636, United States
| | - Chris M Marsay
- Skidaway Institute of Oceanography, Department of Marine Sciences, University of Georgia , Savannah, Georgia 30602-3636, United States
| | - Thorsten Dittmar
- Research Group for Marine Geochemistry (ICBM - MPI Bridging Group), Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg , D-26111 Oldenburg, Germany
| |
Collapse
|
4
|
Koch BP, Ksionzek KB, Lechtenfeld OJ, McCallister SL, Schmitt-Kopplin P, Geuer JK, Geibert W. Response to Comment on “Dissolved organic sulfur in the ocean: Biogeochemistry of a petagram inventory”. Science 2017; 356:813. [DOI: 10.1126/science.aam6328] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 04/07/2017] [Indexed: 11/02/2022]
Affiliation(s)
- Boris P. Koch
- Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany
- MARUM Center for Marine Environmental Sciences, Leobener Straße, D-28359 Bremen, Germany
- University of Applied Sciences, An der Karlstadt 8, 27568 Bremerhaven, Germany
| | - Kerstin B. Ksionzek
- Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany
- MARUM Center for Marine Environmental Sciences, Leobener Straße, D-28359 Bremen, Germany
| | - Oliver J. Lechtenfeld
- Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany
- UFZ-Helmholtz Centre for Environmental Research, Department of Analytical Chemistry, Permoserstraße 15, D-04318 Leipzig, Germany
| | - S. Leigh McCallister
- Virginia Commonwealth University, Department of Biology, Center for Environmental Studies, 1000 West Cary Street, Richmond, VA 23284, USA
| | - Philippe Schmitt-Kopplin
- Helmholtz Zentrum München (HMGU), German Research Centre for Environmental Health, Analytical BioGeoChemistry (BGC), Ingolstädter Landstraße 1, D-85764 Neuherberg, Germany
- Technische Universität München, Chair of Analytical Food Chemistry, Alte Akademie 10, 85354 Freising, Germany
| | - Jana K. Geuer
- Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany
| | - Walter Geibert
- Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany
| |
Collapse
|