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  • Ocean Drilling Program; ODP  (5)
  • DGGE  (2)
Publikationsart
Schlagwörter
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  • 1
    Publikationsdatum: 2022-05-25
    Beschreibung: Author Posting. © Blackwell, 2007. This is the author's version of the work. It is posted here by permission of Blackwell for personal use, not for redistribution. The definitive version was published in Environmental Microbiology 9 (2007): 1001-1016, doi:10.1111/j.1462-2920.2006.01227.x.
    Beschreibung: Within the upper 400 m at western, central, and eastern stations in the world’s largest stratified basin, the Black Sea, we studied the qualitative and quantitative distribution of putative nitrifying Archaea based on their genetic markers (16S rDNA, amoA encoding for the alfa-subunit of archaeal ammonia monooxygenase), and crenarchaeol, the specific glycerol diphytanyl glycerol tetraether (GDGT) of pelagic Crenarchaeota within the Group I.1a. Marine Crenarchaeota were the most abundant Archaea (up to 98% of the total archaeal 16S rDNA copies) in the suboxic layers with oxygen levels as low as 1 μM including layers where previously anammox bacteria were described (Kuypers et al., 2003). Different marine crenarchaeotal phylotypes (both 16S rDNA and amoA) were found at the upper part of the suboxic zone as compared to the base of the suboxic zone and the upper 15-30 m of the anoxic waters with prevailing sulfide concentrations of up to 30 μM. Crenarchaeol concentrations were higher in the sulfidic chemocline as compared to the suboxic zone. These results indicate an abundance of putative nitrifying Archaea at very low oxygen levels within the Black Sea and might form an important source of nitrite for the anammox reaction.
    Beschreibung: This work was supported by a grant from the Netherlands Organization for Scientific Research (VENI Innovational Research Grant nr. 813.13.001 to MJLC), an U. S. National Science Foundation grant OCE0117824 to SGW and the Spinoza award to JSSD, which we greatly acknowledge.
    Schlagwort(e): Black Sea ; Ammonia oxidizing Archaea ; amoA ; Crenarchaeol ; DGGE ; Quantitative real-time PCR
    Repository-Name: Woods Hole Open Access Server
    Materialart: Preprint
    Format: application/pdf
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 2
    Publikationsdatum: 2022-05-25
    Beschreibung: Author Posting. © American Geophysical Union, 2006. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 21 (2006): PA1005, doi:10.1029/2005PA001188.
    Beschreibung: Holocene sea surface temperatures (SST) of the Black Sea have been reconstructed using sedimentary C37 unsaturated alkenones assumed to be derived from the coccolithophorid haptophyte Emiliania huxleyi, whose fossil coccoliths are an important constituent of the unit I sediments. However, alkenones can also be biosynthesized by haptophyte species that do not produce microscopic recognizable coccoliths. A species-specific identification of haptophytes is important in such U 37 K′-based past SST reconstructions since different species have different alkenone-SST calibrations. We showed that 18S rDNA of E. huxleyi made up only a very small percentage (less than 0.8%) of the total eukaryotic 18S rDNA within the up to 3600-year-old fossil record obtained from the depocenter (〉2000 m) of the Black Sea. The predominant fossil 18S rDNA was derived from dinoflagellates (Gymnodinium spp.), which are predominant members of the summer phytoplankton bloom in the modern Black Sea. Using a polymerase chain reaction/denaturing gradient gel electrophoresis method selective for haptophytes, we recovered substantial numbers of a preserved 458-base-pair (bp)-long 18S rDNA fragment of E. huxleyi from the Holocene Black Sea sediments. Additional fossil haptophyte sequences were not detected, indicating that the E. huxleyi alkenone-SST calibration can be applied for at least the last ∼3600 years. The ancient E. huxleyi DNA was well protected against degradation since the DNA/alkenone ratio did not significantly decrease throughout the whole sediment core and 20% of ∼2700-year-old fossil E. huxleyi DNA was still up to 23,000 base pairs long. We showed that fossil DNA offers great potential to study the Holocene paleoecology and paleoenvironment of anoxic deep-sea settings in unprecedented detail.
    Beschreibung: This work was supported by a grant from the Netherlands Organization for Scientific Research (NWO) (Open Competition Program 813.13.001 to M.J.L.C.) and NSF grant OCE0117824 to S.G.W., which we greatly appreciate.
    Schlagwort(e): Fossil DNA ; DGGE ; Paleoecology ; Holocene ; Black Sea ; Ancient haptophytes
    Repository-Name: Woods Hole Open Access Server
    Materialart: Article
    Format: application/pdf
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 3
    facet.materialart.
    Unbekannt
    PANGAEA
    In:  Supplement to: Hoefs, Marcel JL; Versteegh, Gerard J M; Rijpstra, W Irene C; de Leeuw, Jan W; Sinninghe Damsté, Jaap S (1998): Postdepositional oxic degradation of alkenones: Implications for the measurement of palaeo sea surface temperatures. Paleoceanography, 13(1), 42-49, https://doi.org/10.1029/97PA02893
    Publikationsdatum: 2024-01-09
    Beschreibung: Free and 'bound' long-chain alkenones (C37:2 and C37:3) in oxidized and unoxidized sections of four organic matter-rich Pliocene and Miocene Madeira Abyssal Plain turbidites (one from Ocean Drilling Program site 951B and three from site 952A) were analyzed to determine the effect of severe post depositional oxidation on the value of Uk'37. The profiles of both alkenones across the redox boundary show a preferential degradation of the C37:3 compared to the C37:2 compound. Because of the high initial Uk'37 values and the way of calculating the Uk'37 this degradation hardly influences the Uk'37 profiles. However, for lower Uk'37 values, measured selective degradation would increase Uk'37 up to 0.17 units, equivalent to 5°C. For most of the Uk'37 band-width, much smaller degradation already increases Uk'37 beyond the analytical error (0.017 units). Consequently, for interpreting the Uk'37 record in terms of past sea surface temperatures, selective degradation needs serious consideration.
    Schlagwort(e): Ocean Drilling Program; ODP
    Materialart: Dataset
    Format: application/zip, 2 datasets
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 4
    facet.materialart.
    Unbekannt
    PANGAEA
    In:  Supplement to: Frieling, Joost; Peterse, Francien; Lunt, Daniel J; Bohaty, Steven M; Sinninghe Damsté, Jaap S; Reichart, Gert-Jan; Sluijs, Appy (2019): Widespread warming before and elevated barium burial during the Paleocene-Eocene Thermal Maximum: evidence for methane hydrate release? Paleoceanography and Paleoclimatology, https://doi.org/10.1029/2018PA003425
    Publikationsdatum: 2024-01-09
    Beschreibung: Current climate change may induce positive carbon cycle feedbacks that amplify anthropogenic warming on time scales of centuries to millennia. Similar feedbacks might have been active during a phase of carbon cycle perturbation and global warming, termed the Paleocene-Eocene Thermal Maximum (PETM, 56 million years ago). The PETM may help constrain these feedbacks and their sensitivity to warming. We present new high-resolution carbon isotope and sea surface temperature data from Ocean Drilling Project Site 959 in the Equatorial Atlantic. With these and existing data from the New Jersey shelf and Maud Rise, Southern Ocean, we quantify the lead-lag relation between PETM warming and the carbon input that caused the carbon isotope excursion. We show ~2 ºC of global warming preceded the CIE by millennia, strongly implicating CO2-driven warming triggered a positive carbon cycle feedback. We further compile new and published barium (Ba) records encompassing continental shelf, slope and deep-ocean settings. Based on this compilation, average Ba burial rates approximately tripled during the PETM, which may require an additional source of Ba to the ocean. Although the precipitation pathway is not well constrained, dissolved Ba stored in sulfate-depleted pore-waters below methane hydrates could represent an additional source. We speculate the most complete explanation for early warming and rise in Ba supply is that hydrate dissociation acted as a positive feedback and caused the CIE. This could imply hydrates are more temperature-sensitive than previously considered, and may warrant reconsideration of the political assignment of 2 °C warming as a safe future scenario.
    Schlagwort(e): Ocean Drilling Program; ODP
    Materialart: Dataset
    Format: application/zip, 4 datasets
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 5
    facet.materialart.
    Unbekannt
    PANGAEA
    In:  Supplement to: Smittenberg, Rienk H; Hopmans, Ellen C; Schouten, Stefan; Hayes, John M; Eglinton, Timothy Ian; Sinninghe Damsté, Jaap S (2004): Compound-specific radiocarbon dating of the varved Holocene sedimentary record of Saanich Inlet, Canada. Paleoceanography, 19(2), PA2012, https://doi.org/10.1029/2003PA000927
    Publikationsdatum: 2024-01-09
    Beschreibung: The radiocarbon contents of various biomarkers extracted from the varve-counted sediments of Saanich Inlet, Canada, were determined to assess their applicability for dating purposes. Calibrated ages obtained from the marine planktonic archaeal biomarker crenarchaeol compared favorably with varve-count ages. The same conclusion could be drawn for a more general archaeal biomarker (GDGT-0), although this biomarker proved to be less reliable due to its less-specific origin. The results also lend support to earlier indications that marine crenarchaeota use dissolved inorganic carbon (DIC) as their carbon source. The average reservoir age offset DR of 430 years, determined using the crenarchaeol radiocarbon ages, varied by ±110 years. This may be caused by natural variations in ocean-atmosphere mixing or upwelling at the NE Pacific coast but variability may also be due to an inconsistency in the marine calibration curve when used at sites with high reservoir ages.
    Schlagwort(e): Ocean Drilling Program; ODP
    Materialart: Dataset
    Format: application/zip, 7 datasets
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 6
    facet.materialart.
    Unbekannt
    PANGAEA
    In:  Supplement to: Schouten, Stefan; Eldrett, James S; Greenwood, David R; Harding, Ian C; Baas, Marianne; Sinninghe Damsté, Jaap S (2008): Onset of long-term cooling of Greenland near the Eocene-Oligocene boundary as revealed by branched tetraether lipids. Geology, 36(2), 147, https://doi.org/10.1130/G24332A.1
    Publikationsdatum: 2024-01-09
    Beschreibung: The Eocene-Oligocene (E-O) boundary interval is considered to be one of the major transitions in Earth's climate, witnessing the first major expansion of the East Antarctic Ice Sheet. However, the extent of the associated climatic cooling, especially for high northern latitude continental landmasses, is poorly constrained. In this study we reconstruct the first mean annual air temperature (MAAT) for the Greenland landmass during the late Eocene and early Oligocene by applying a new proxy based on the distribution of branched tetraether lipids derived from soil bacteria preserved in a marine sediment core from the Greenland Basin. The temperature estimates are compared with a composite continental temperature record based on bio-climatic analysis of pollen assemblages. Both proxies reveal comparable late Eocene MAATs of ~13-15 °C and a gradual long-term cooling of ~3-5 °C starting near the E-O boundary. These data are in agreement with other MAAT reconstructions from northern midlatitude continents and suggest a general cooling of the Northern Hemisphere during the E-O transition.
    Schlagwort(e): Ocean Drilling Program; ODP
    Materialart: Dataset
    Format: application/zip, 3 datasets
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 7
    facet.materialart.
    Unbekannt
    PANGAEA
    In:  Supplement to: Peterse, Francien; van der Meer, Jaap; Schouten, Stefan; Weijers, Johan W H; Fierer, Noah; Jackson, Robert B; Kim, Jung-Hyun; Sinninghe Damsté, Jaap S (2012): Revised calibration of the MBT–CBT paleotemperature proxy based on branched tetraether membrane lipids in surface soils. Geochimica et Cosmochimica Acta, 96, 215-229, https://doi.org/10.1016/j.gca.2012.08.011
    Publikationsdatum: 2024-01-09
    Beschreibung: The MBT-CBT proxy for the reconstruction of paleotemperatures and past soil pH is based on the distribution of branched glycerol dialkyl glycerol tetraether (brGDGT) membrane lipids. The Methylation of Branched Tetraether (MBT) and the Cyclisation of Branched Tetraether (CBT) indices were developed to quantify these distributions, and significant empirical relations between these indices and annual mean air temperature (MAT) and/or soil pH were found in a large data set of soils. In this study, we extended this soil dataset to 278 globally distributed surface soils. Of these soils, 26% contains all nine brGDGTs, while in 63% of the soils the seven most common brGDGTs were detected, and the latter were selected for calibration purposes. This resulted in new transfer functions for the reconstruction of pH based on the CBT index: pH = 7.90-1.97 × CBT (r**2 = 0.70; RMSE = 0.8; n = 176), as well as for MAT based on the CBT index and methylation index based on the seven most abundant GDGTs (defined as MBT'): MAT = 0.81-5.67 × CBT + 31.0 × MBT' (r**2 = 0.59; RMSE = 5.0 °C; n = 176). The new transfer function for MAT has a substantially lower correlation coefficient than the original equation (r**2 = 0.77). To investigate possible improvement of the correlation, we used our extended global surface soil dataset to statistically derive the indices that best describe the relations of brGDGT composition with MAT and soil pH. These new indices, however, resulted in only a relatively minor increase in correlation coefficients, while they cannot be explained straightforwardly by physiological mechanisms. The large scatter in the calibration cannot be fully explained by local factors or by seasonality, but MAT for soils from arid regions are generally substantially (up to 20 °C) underestimated, suggesting that absolute brGDGT-based temperature records for these areas should be interpreted with caution. The applicability of the new MBT'-CBT calibration function was tested using previously published MBT-CBT-derived paleotemperature records covering the last deglaciation in Central Africa and East Asia, the Eocene-Oligocene boundary and the Paleocene-Eocene thermal maximum. The results show that trends remain similar in all records, but that absolute temperature estimates and the amplitude of temperature changes are lower for most records, and generally in better agreement with independent proxy data.
    Schlagwort(e): Ocean Drilling Program; ODP
    Materialart: Dataset
    Format: application/zip, 3 datasets
    Standort Signatur Einschränkungen Verfügbarkeit
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