Gan, Shuchai; Heuer, Verena B; Adhikari, Rishi Ram; Wörmer, Lars: A study on how moderate heating renders 7.8 million-year-old organic matter bioavailable in deep marine sediments [dataset bundled publication]. PANGAEA, https://doi.pangaea.de/10.1594/PANGAEA.973415 (dataset in review)
Abstract:
In laboratory experiments on field-collected sediments, we investigated 7.8 million-year-old sediment from a site off the Nankai Trough, Japan, through incubation experiments to simulate future burial conditions. In a 55-day laboratory experiment, we incubated sediment slurried with artificial seawater in four subsets at 20°C (control), and at 35°C, 55°C, and 85°C to simulate future heating during burial and conditions favorable for mesophilic, thermophilic, and hyperthermophilic microorganisms, respectively. We investigated changes in dissolved organic matter quality as a function of microbial activity and temperature using 3D fluorescence spectroscopy (EEMs) and FT-ICR-MS, and analyzed dissolved manganese, iron, and sulfur to detect changes in the sediment's mineral matrix. We observed temperature- and time-dependent changes in the dissolved organic matter (DOM) pool. At 20°C, biotic production of protein-like DOM was predominant, ceasing at higher temperatures. Above 35°C, both protein-like and humic-like DOM were released upon heating, but their reactivity was low. At 55°C, abiotic decomposition of humic compounds led to the generation of protein-like DOM. By 85°C, the DOM composition shifted significantly, with larger molecules rapidly released and nitrogen-containing compounds decomposed, producing H2 and acetate. Data contains (1) bulk parameters about organics and inorganics in the dissolved phase, (2) release of the acetate during laboratory experiments, (3) details about the formulae characterized by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS).
Keyword(s):
deep biosphere; DOM; Drilling Vessel DV Chikyu; humic decomposition; Hydrogenase; International Ocean Drilling Program (IODP); IODP Expedition 322; microbial carbon pump; mineral carbon pump; Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE); Site C0012; "Subduction Inputs"; thermal environment
Related to:
Gan, Shuchai; Heuer, Verena B; Schmidt, Frauke; Wörmer, Lars; Wang, Faming; Adhikari, Rishi Ram; Hinrichs, Kai-Uwe (submitted): A study on how moderate heating renders 7.8 million-year-old organic matter bioavailable in deep marine sediments. Nature Communications
Project(s):
Funding:
German Research Foundation (DFG), grant/award no. 387745511: Exploring the impact of temperature on dissolved organic matter and life in the deep biosphere off Muroto, Nankai Trough (IODP Expedition 370)
German Research Foundation (DFG), grant/award no. 390741603: EXC 2077: The Ocean Floor – Earth's Uncharted Interface
Coverage:
Latitude: 32.748000 * Longitude: 136.917000
License:
Creative Commons Attribution 4.0 International (CC-BY-4.0) (License comes into effect after moratorium ends)
Size:
3 datasets
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Datasets listed in this bundled publication
- Gan, S; Heuer, VB; Adhikari, RR et al. (in review): Bulk parameters during incubation of sediment core 322-C0012. https://doi.pangaea.de/10.1594/PANGAEA.973411
- Gan, S; Heuer, VB; Adhikari, RR et al. (in review): Concentration changes of acetate during incubation of sediment core 322-C0012. https://doi.pangaea.de/10.1594/PANGAEA.973413
- Gan, S; Heuer, VB; Adhikari, RR et al. (in review): Transformation of dissolved organic matter chracterized by FT-ICR-MS during incubation of sediment core 322-C0012. https://doi.pangaea.de/10.1594/PANGAEA.973414