GLORIA

GEOMAR Library Ocean Research Information Access

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 2-C-methylerythritol-4-phosphate pathway  (1)
  • 202-1234; AGE; Alkenone, C37 per unit sediment mass; Alkenone C37:2, δD; Alkenone C37:2, δD, standard deviation; Alkenone C37:3, δD; Alkenone C37:3, δD, standard deviation; Alkenones; Chile Margin; COMPCORE; Composite Core; Depth, composite; Hydrogen isotopes; Ice volume corrected; Joides Resolution; Leg202; NIOZ_UU; NIOZ Royal Netherlands Institute for Sea Research, and Utrecht University; Ocean Drilling Program; ODP; paleosalinity; South Pacific Ocean; δ Deuterium, alkenone, C37; δ Deuterium, alkenone, C37, standard deviation  (1)
  • 64PE304; 64PE304-80; AGE; Alkenone C37/C38 ratio; Branched and isoprenoid tetraether index; DEPTH, sediment/rock; GC; Gravity corer; INATEX-GEO; Pelagia; South-East African margin; δ Deuterium, alkenone; δ Deuterium, alkenone, standard deviation  (1)
Document type
Keywords
Publisher
Years
  • 1
    facet.materialart.
    Unknown
    delta Deuterium of alkenone and BIT index of sediment core 64PE304-80 samples (2014)
    PANGAEA
    In:  Supplement to: Kasper, Sebastian; van der Meer, Marcel T J; Castañeda, Isla S; Tjallingii, Rik; Brummer, Geert-Jan A; Sinninghe Damsté, Jaap S; Schouten, Stefan (2015): Testing alkenone D/H ratio as a paleo indicator of sea surface salinity in a coastal ocean margin (Mozambique Channel). Organic Geochemistry, 78, 62-68, https://doi.org/10.1016/j.orggeochem.2014.10.011
    Details
    Publication Date: 2023-12-22
    Description: Reconstructing past ocean salinity is important for assessing paleoceanographic change and therefore past climatic dynamics. Commonly, sea water salinity reconstruction is based on foraminifera oxygen isotope ratio values combined with sea surface temperature reconstruction. However, the approach relies on multiple proxies, resulting in relatively large uncertainty and, consequently, relatively low accuracy of salinity estimates. An alternative tool for past ocean salinity reconstruction is the hydrogen isotope composition of long chain (C37) alkenones (dDalkenone). Here, we applied dDalkenone to a 39 ka long coastal sediment record from the Eastern South African continental shelf in the Mozambique Channel, close to the Zambezi River mouth. Despite changes in global sea water dD related to glacial - interglacial ice volume effects, no clear changes were observed in the dDalkenone record throughout the entire 39 ka. The BIT index record from the same core showed high BIT values during the glacial and low values during the Holocene. This indicates a more pronounced freshwater influence at the core location during the glacial, resulting in alkenones depleted in deuterium during that time and, thereby, explains the lack of a clear glacial-interglacial alkenone dD shift. Correlation between the BIT index and dDalkenone during the glacial period suggests that increased continental runoff potentially changed the growth conditions of the alkenone producing haptophytes, promoting coastal haptophyte species with generally more enriched dDalkenone values. We therefore suggest that the application of dDalkenone for reconstructing past salinity in coastal settings may be complicated by changes in the alkenone producing haptophyte community.
    Keywords: 64PE304; 64PE304-80; AGE; Alkenone C37/C38 ratio; Branched and isoprenoid tetraether index; DEPTH, sediment/rock; GC; Gravity corer; INATEX-GEO; Pelagia; South-East African margin; δ Deuterium, alkenone; δ Deuterium, alkenone, standard deviation
    Type: Dataset
    Format: text/tab-separated-values, 591 data points
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    DATA PANGAEA
  • 2
    facet.materialart.
    Unknown
    Hydrogen isotope ratios of alkenones from ODP Site 202-1234 (2019)
    PANGAEA
    In:  Supplement to: Weiss, Gabriella M; de Bar, Marijke W; Stolwjik, D J; Schouten, Stefan; Sinninghe Damsté, Jaap S; van der Meer, Marcel T J (2019): Paleosensitivity of Hydrogen Isotope Ratios of Long‐Chain Alkenones to Salinity Changes at the Chile Margin. Paleoceanography and Paleoclimatology, 34(6), 978-989, https://doi.org/10.1029/2019PA003591
    Details
    Publication Date: 2024-01-09
    Description: Hydrogen isotope ratios of long-chain alkenones (δ2HC37 ratios) have been shown to correlate with salinity in several culture studies. However, it is uncertain how applicable the δ2HC37-salinity relationship is to reconstruct past salinity. δ2HC37 ratios were measured on sediments from a drill core (ODP site 1234) at the Chilean Margin covering the last ~150 kyr. High δ2HC37 values correspond to glacial time periods and interglacial periods are characterized by lower δ2HC37 values, aligning with δ18O ratios measured on planktonic foraminifera from the same core. Effects of parameters such as species composition, the δ2H-δ18O relationship used for ice volume corrections, and nutrient or light controlled growth rate, do not appear to significantly alter δ2HC37 ratios at ODP 1234. We use linear regression equations from batch culture experiments, marine surface sediments, and suspended particulate organic matter to quantitatively characterize salinity changes over the last ~150 kyr at ODP 1234. However, most of these equations yield larger salinity shifts than previously suggested, a phenomenon also observed for other δ2HC37 records. This suggests that the paleosensitivity of δ2HC37 ratios to salinity is larger in the geologic record than has been observed in any modern environment or laboratory settings, or that glacial to interglacial salinity shifts might be larger than currently believed.
    Keywords: 202-1234; AGE; Alkenone, C37 per unit sediment mass; Alkenone C37:2, δD; Alkenone C37:2, δD, standard deviation; Alkenone C37:3, δD; Alkenone C37:3, δD, standard deviation; Alkenones; Chile Margin; COMPCORE; Composite Core; Depth, composite; Hydrogen isotopes; Ice volume corrected; Joides Resolution; Leg202; NIOZ_UU; NIOZ Royal Netherlands Institute for Sea Research, and Utrecht University; Ocean Drilling Program; ODP; paleosalinity; South Pacific Ocean; δ Deuterium, alkenone, C37; δ Deuterium, alkenone, C37, standard deviation
    Type: Dataset
    Format: text/tab-separated-values, 648 data points
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    DATA PANGAEA
  • 3
    facet.materialart.
    Unknown
    Evidence for substantial intramolecular heterogeneity in the stable carbon isotopic composition of phytol in photoautotrophic organisms (2008)
    Details
    Publication Date: 2022-05-25
    Description: Author Posting. © Elsevier B.V., 2007. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Organic Geochemistry 39 (2008): 135-146, doi:10.1016/j.orggeochem.2007.09.002.
    Description: The ubiquitous isoprenoid phytol was isolated from a range of algae, terrestrial plants and a bacterium and its two terminal carbon atoms were quantitatively removed by chemical oxidation. The product, 6,10,14-trimethylpentadecan-2-one, was depleted in 13C by 1-4‰ relative to the parent phytol. This difference is significant, and indicates that the pathway for biosynthesis of phytol induces substantial intramolecular stable carbon isotopic fractionations. The nature and magnitude of the fractionations suggest strongly that it is associated both with the biosynthesis of isopentenyl pyrophosphate via the 2-C-methylerythritol-4-phosphate pathway and with the formation of carotenoids and phytol from geranyl-geraniolphosphate. As a result of these large, intramolecular isotopic differences, diagenetic products formed by loss of C, such as pristane, may be naturally depleted in 13C by several permil relative to phytane.
    Description: Shell International Petroleum Maatschappij BV is thanked for financial support for the irm- GC-MS facility
    Keywords: Phytol ; Phytane ; Pristane ; Stable carbon isotope ; Mevalonic acid pathway ; 2-C-methylerythritol-4-phosphate pathway ; 2,6,10-trimethylpentadecan-2-one
    Repository Name: Woods Hole Open Access Server
    Type: Preprint
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER (OA)
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...