Hostname: page-component-cd9895bd7-lnqnp Total loading time: 0 Render date: 2024-12-27T10:34:23.387Z Has data issue: false hasContentIssue false

Effect of Acidified Versus Frozen Storage on Marine Dissolved Organic Carbon Concentration and Isotopic Composition

Published online by Cambridge University Press:  26 July 2016

Brett D Walker*
Affiliation:
Department of Earth System Science, University of California Irvine, Irvine, California 92697-3100, USA
Sheila Griffin
Affiliation:
Department of Earth System Science, University of California Irvine, Irvine, California 92697-3100, USA
Ellen R M Druffel
Affiliation:
Department of Earth System Science, University of California Irvine, Irvine, California 92697-3100, USA
*
*Corresponding author. Email: [email protected].

Abstract

The standard procedure for storing/preserving seawater dissolved organic carbon (DOC) samples after field collection is by freezing (–20°C) until future analysis can be made. However, shipping and receiving large numbers of these samples without thawing presents a significant logistical problem and large monetary expense. Access to freezers can also be limited in remote field locations. We therefore test an alternative method of preserving and storing samples for the measurement of DOC concentrations ([DOC]), stable carbon (δ13C), and radiocarbon (as ∆14C) isotopic values via UV photooxidation (UVox). We report a total analytical reproducibility of frozen DOC samples to be [DOC]±1.3 µM, ∆14C±9.4‰, and δ13C±0.1‰, comparable to previously reported results (Druffel et al. 2013). Open Ocean DOC frozen versus acidified duplicates were on average offset by ∆DOC±1.1 µM, ∆∆14C± –1.3‰, and ∆δ13C± –0.1‰. Coastal Ocean frozen vs. acidified sample replicates, collected as part of a long-term (380-day) storage experiment, had larger, albeit consistent offsets of ∆DOC±2.2 µM, ∆∆14C±1.5‰, and ∆δ13C± –0.2‰. A simple isotopic mass balance of changes in [DOC], ∆14C, and δ13C values reveals loss of semi-labile DOC (2.2±0.6 µM, ∆14C=–94±105‰, δ13C=–27±10‰; n=4) and semi-recalcitrant DOC (2.4±0.7 µM, ∆14C=–478±116‰, δ13C=–23.4±3.0‰; n=3) in Coastal and Open Ocean acidified samples, respectively.

Type
Chemical Pretreatment Approaches
Copyright
© 2016 by the Arizona Board of Regents on behalf of the University of Arizona 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

Selected Papers from the 2015 Radiocarbon Conference, Dakar, Senegal, 16–20 November 2015

References

REFERENCES

Beaupre, SR, Druffel, ERM, Griffin, S. 2007. A low-blank photochemical extraction system for concentration and isotopic analyses of marine dissolved organic carbon. Limnology and Oceanography-Methods 5(6):174184.CrossRefGoogle Scholar
Benner, R, Amon, RMW. 2015. The size-reactivity continuum of major bioelements in the ocean. Annual Review of Marine Science 7(1):185205.CrossRefGoogle ScholarPubMed
Calleja, ML, Batista, F, Peacock, M, Kudela, R, McCarthy, MD. 2013. Changes in compound specific delta N-15 amino acid signatures and D/L ratios in marine dissolved organic matter induced by heterotrophic bacterial reworking. Marine Chemistry 149:3244.CrossRefGoogle Scholar
Cherrier, J, Bauer, JE, Druffel, ERM, Coffin, RB, Chanton, JP. 1999. Radiocarbon in marine bacteria: evidence for the ages of assimilated carbon. Limnology and Oceanography 44(3):730736.CrossRefGoogle Scholar
Druffel, ERM, Griffin, S, Walker, BD, Coppola, AI, Glynn, DS. 2013. Total uncertainty of radiocarbon measurements of marine dissolved organic carbon and methodological recommendations. Radiocarbon 55(2–3):11351141.CrossRefGoogle Scholar
Gasol, JM, Alonso-Saez, L, Vaque, D, Baltar, F, Calleja, ML, Duarte, CM, Aristegui, J. 2009. Mesopelagic prokaryotic bulk and single-cell heterotrophic activity and community composition in the NW Africa-Canary Islands coastal-transition zone. Progress in Oceanography 83(1–4):189196.CrossRefGoogle Scholar
Griffin, S, Beaupre, SR, Druffel, ERM. 2010. An alternate method of diluting dissolved organic carbon seawater samples for 14C analysis. Radiocarbon 52(2–3):12241229.CrossRefGoogle Scholar
Griffith, DR, McNichol, AP, Xu, L, McLaughlin, FA, Macdonald, RW, Brown, KA, Eglinton, TI. 2012. Carbon dynamics in the western Arctic Ocean: insights from full-depth carbon isotope profiles of DIC, DOC, and POC. Biogeosciences 9(3):12171224.CrossRefGoogle Scholar
Guo, LD, Santschi, PH, Cifuentes, LA, Trumbore, SE, Southon, J. 1996. Cycling of high-molecular-weight dissolved organic matter in the middle Atlantic bight as revealed by carbon isotopic (13C and 14C) signatures. Limnology and Oceanography 41(6):12421252.CrossRefGoogle Scholar
Hertkorn, N, Benner, R, Frommberger, M, Schmitt-Kopplin, P, Witt, M, Kaiser, K, Kettrup, A, Hedges, JI. 2006. Characterization of a major refractory component of marine dissolved organic matter. Geochimica et Cosmochimica Acta 70(12):29903010.CrossRefGoogle Scholar
Hwang, J, Druffel, ERM, Eglinton, TI. 2010. Widespread influence of resuspended sediments on oceanic particulate organic carbon: insights from radiocarbon and aluminum contents in sinking particles. Global Biogeochemical Cycles 24(4):GB4016.CrossRefGoogle Scholar
McMurry, J. 2011. Organic Chemistry. Belmont: Cengage Learning. 1376 p.Google Scholar
Ruiz-Halpern, S, Calleja, ML, Dachs, J, Del Vento, S, Pastor, M, Palmer, M, Agusti, S, Duarte, CM. 2014. Ocean-atmosphere exchange of organic carbon and CO2 surrounding the Antarctic Peninsula. Biogeosciences 11(10):27552770.CrossRefGoogle Scholar
Sharp, JH, Carlson, CA, Peltzer, ET, Castle-Ward, DM, Savidge, KB, Rinker, KR. 2002. Final dissolved organic carbon broad community intercalibration and preliminary use of DOC reference materials. Marine Chemistry 77(4):239253.CrossRefGoogle Scholar
Sugimura, Y, Suzuki, Y. 1988. A high-temperature catalytic-oxidation method for the determinatino of non-volatile dissolved organic carbon in seawater by direct injection of a liquid sample. Marine Chemistry 24(2):105131.CrossRefGoogle Scholar
Suzuki, Y. 1993. On the measurement of DOC and DON in seawater. Marine Chemistry 41(1–3):287288.CrossRefGoogle Scholar
Tupas, LM, Popp, BN, Karl, DM. 1994. Dissolved organic carbon in oligotrophic waters – experiments on sample preservation, storage and analysis. Marine Chemistry 45(3):207216.CrossRefGoogle Scholar
Vogel, JS, Southon, JR, Nelson, DE, Brown, TA. 1984. Performance of catalytically condensed carbon for use in accelerator mass spectrometry. Nuclear Instruments and Methods in Physics Research B 5(2):289293.CrossRefGoogle Scholar
Vogel, JS, Southon, JR, Nelson, DE. 1987. Catalyst and binder effects in the use of filamentous graphite for AMS. Nuclear Instruments and Methods in Physics Research B 29(1–2):5056.CrossRefGoogle Scholar
Walker, BD, Beaupre, SR, Guilderson, TP, Druffel, ERM, McCarthy, MD. 2011. Large-volume ultrafiltration for the study of radiocarbon signatures and size vs. age relationships in marine dissolved organic matter. Geochimica Cosmochimica Acta 75(18):51875202.CrossRefGoogle Scholar
Walker, BD, Guilderson, T, Okimura, KM, Peacock, M, McCarthy, M. 2014. Radiocarbon signatures and size-age-composition relationships of major organic matter pools within a unique California upwelling system. Geochimica et Cosmochimica Acta 126:117.CrossRefGoogle Scholar
Williams, PM, Oeschger, H, Kinney, P. 1969. Natural radiocarbon activity of dissolved organic carbon in north-east Pacific Ocean. Nature 224(5216):256258.CrossRefGoogle Scholar
Xu, XM, Trumbore, SE, Zheng, SH, Southon, JR, McDuffee, KE, Luttgen, M, Liu, JC. 2007. Modifying a sealed tube zinc reduction method for preparation of AMS graphite targets: reducing background and attaining high precision. Nuclear Instruments and Methods in Physics Research B 259(1):320329.CrossRefGoogle Scholar
Xue, Y, Ge, T, Wang, X. 2015. An effective method of UV-oxidation of dissolved organic carbon in natural waters for radiocarbon analysis by accelerator mass spectrometry. Journal of Ocean University of China 14(6):989993.CrossRefGoogle Scholar
Supplementary material: File

Walker supplementary material

Walker supplementary material 1

Download Walker supplementary material(File)
File 31.5 KB