Transfer of organic carbon through marine water columns to sediments – insights from stable and radiocarbon isotopes of lipid biomarkers

Compound-specific <sup>13</sup>C and <sup>14</sup>C compositions of diverse lipid biomarkers (fatty acids, alkenones, hydrocarbons, sterols and fatty alcohols) were measured in sinking particulate matter collected in sediment traps and from underlying surface sediments in the...

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Main Authors: S. G. Wakeham, A. P. McNichol
Format: Article
Language:English
Published: Copernicus Publications 2014-12-01
Series:Biogeosciences
Online Access:http://www.biogeosciences.net/11/6895/2014/bg-11-6895-2014.pdf
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author S. G. Wakeham
A. P. McNichol
author_facet S. G. Wakeham
A. P. McNichol
author_sort S. G. Wakeham
collection DOAJ
description Compound-specific <sup>13</sup>C and <sup>14</sup>C compositions of diverse lipid biomarkers (fatty acids, alkenones, hydrocarbons, sterols and fatty alcohols) were measured in sinking particulate matter collected in sediment traps and from underlying surface sediments in the Black Sea, the Arabian Sea and the Ross Sea. The goal was to develop a multiparameter approach to constrain relative inputs of organic carbon (OC) from marine biomass, terrigenous vascular-plant and relict-kerogen sources. Using an isotope mass balance, we calculate that marine biomass in sediment trap material from the Black Sea and Arabian Sea accounted for 66–100% of OC, with lower terrigenous (3–8%) and relict (4–16%) contributions. Marine biomass in sediments constituted lower proportions of OC (66–90%), with consequentially higher proportions of terrigenous and relict carbon (3–17 and 7–13%, respectively). Ross Sea data were insufficient to allow similar mass balance calculations. These results suggest that, whereas particulate organic carbon is overwhelmingly marine in origin, pre-aged allochthonous terrigenous and relict OC become proportionally more important in sediments, consistent with pre-aged OC being better preserved during vertical transport to and burial at the seafloor than the upper-ocean-derived marine OC.
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spelling doaj.art-c50df7922a384ecab6efe7f88cb3d1002022-12-21T17:32:03ZengCopernicus PublicationsBiogeosciences1726-41701726-41892014-12-0111236895691410.5194/bg-11-6895-2014Transfer of organic carbon through marine water columns to sediments &ndash; insights from stable and radiocarbon isotopes of lipid biomarkersS. G. Wakeham0A. P. McNichol1Skidaway Institute of Oceanography, 10 Ocean Science Circle, Savannah, GA 31411, USANational Ocean Sciences Accelerator Mass Spectrometer Facility (NOSAMS), Woods Hole Oceanographic Institution, McLean Laboratory, Mail Stop #8, 266 Woods Hole Road,Woods Hole, MA 02543-1539, USACompound-specific <sup>13</sup>C and <sup>14</sup>C compositions of diverse lipid biomarkers (fatty acids, alkenones, hydrocarbons, sterols and fatty alcohols) were measured in sinking particulate matter collected in sediment traps and from underlying surface sediments in the Black Sea, the Arabian Sea and the Ross Sea. The goal was to develop a multiparameter approach to constrain relative inputs of organic carbon (OC) from marine biomass, terrigenous vascular-plant and relict-kerogen sources. Using an isotope mass balance, we calculate that marine biomass in sediment trap material from the Black Sea and Arabian Sea accounted for 66–100% of OC, with lower terrigenous (3–8%) and relict (4–16%) contributions. Marine biomass in sediments constituted lower proportions of OC (66–90%), with consequentially higher proportions of terrigenous and relict carbon (3–17 and 7–13%, respectively). Ross Sea data were insufficient to allow similar mass balance calculations. These results suggest that, whereas particulate organic carbon is overwhelmingly marine in origin, pre-aged allochthonous terrigenous and relict OC become proportionally more important in sediments, consistent with pre-aged OC being better preserved during vertical transport to and burial at the seafloor than the upper-ocean-derived marine OC.http://www.biogeosciences.net/11/6895/2014/bg-11-6895-2014.pdf
spellingShingle S. G. Wakeham
A. P. McNichol
Transfer of organic carbon through marine water columns to sediments &ndash; insights from stable and radiocarbon isotopes of lipid biomarkers
Biogeosciences
title Transfer of organic carbon through marine water columns to sediments &ndash; insights from stable and radiocarbon isotopes of lipid biomarkers
title_full Transfer of organic carbon through marine water columns to sediments &ndash; insights from stable and radiocarbon isotopes of lipid biomarkers
title_fullStr Transfer of organic carbon through marine water columns to sediments &ndash; insights from stable and radiocarbon isotopes of lipid biomarkers
title_full_unstemmed Transfer of organic carbon through marine water columns to sediments &ndash; insights from stable and radiocarbon isotopes of lipid biomarkers
title_short Transfer of organic carbon through marine water columns to sediments &ndash; insights from stable and radiocarbon isotopes of lipid biomarkers
title_sort transfer of organic carbon through marine water columns to sediments ndash insights from stable and radiocarbon isotopes of lipid biomarkers
url http://www.biogeosciences.net/11/6895/2014/bg-11-6895-2014.pdf
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AT apmcnichol transferoforganiccarbonthroughmarinewatercolumnstosedimentsndashinsightsfromstableandradiocarbonisotopesoflipidbiomarkers