Articles | Volume 17, issue 19
https://doi.org/10.5194/bg-17-4919-2020
https://doi.org/10.5194/bg-17-4919-2020
Research article
 | 
14 Oct 2020
Research article |  | 14 Oct 2020

Effects of 238U variability and physical transport on water column 234Th downward fluxes in the coastal upwelling system off Peru

Ruifang C. Xie, Frédéric A. C. Le Moigne, Insa Rapp, Jan Lüdke, Beat Gasser, Marcus Dengler, Volker Liebetrau, and Eric P. Achterberg

Related authors

Regulation of nitrous oxide production in low-oxygen waters off the coast of Peru
Claudia Frey, Hermann W. Bange, Eric P. Achterberg, Amal Jayakumar, Carolin R. Löscher, Damian L. Arévalo-Martínez, Elizabeth León-Palmero, Mingshuang Sun, Xin Sun, Ruifang C. Xie, Sergey Oleynik, and Bess B. Ward
Biogeosciences, 17, 2263–2287, https://doi.org/10.5194/bg-17-2263-2020,https://doi.org/10.5194/bg-17-2263-2020, 2020
Short summary

Related subject area

Biogeochemistry: Stable Isotopes & Other Tracers
Sea ice and mixed layer depth influence on nitrate depletion and associated isotopic effects in the Drake Passage–Weddell Sea region, Southern Ocean
Aymeric P. M. Servettaz, Yuta Isaji, Chisato Yoshikawa, Yanghee Jang, Boo-Keun Khim, Yeongjun Ryu, Daniel M. Sigman, Nanako O. Ogawa, Francisco J. Jiménez-Espejo, and Naohiko Ohkouchi
Biogeosciences, 22, 2239–2260, https://doi.org/10.5194/bg-22-2239-2025,https://doi.org/10.5194/bg-22-2239-2025, 2025
Short summary
Stable iron isotope signals indicate a “pseudo-abiotic” process driving deep iron release in methanic sediments
Susann Henkel, Bo Liu, Michael Staubwasser, Simone A. Kasemann, Anette Meixner, David A. Aromokeye, Michael W. Friedrich, and Sabine Kasten
Biogeosciences, 22, 1673–1696, https://doi.org/10.5194/bg-22-1673-2025,https://doi.org/10.5194/bg-22-1673-2025, 2025
Short summary
How long does carbon stay in a near-pristine central Amazon forest? An empirical estimate with radiocarbon
Ingrid Chanca, Ingeborg Levin, Susan Trumbore, Kita Macario, Jost Lavric, Carlos Alberto Quesada, Alessandro Carioca de Araújo, Cléo Quaresma Dias Júnior, Hella van Asperen, Samuel Hammer, and Carlos A. Sierra
Biogeosciences, 22, 455–472, https://doi.org/10.5194/bg-22-455-2025,https://doi.org/10.5194/bg-22-455-2025, 2025
Short summary
No increase is detected and modeled for the seasonal cycle amplitude of δ13C of atmospheric carbon dioxide
Fortunat Joos, Sebastian Lienert, and Sönke Zaehle
Biogeosciences, 22, 19–39, https://doi.org/10.5194/bg-22-19-2025,https://doi.org/10.5194/bg-22-19-2025, 2025
Short summary
Fungi present distinguishable isotopic signals when grown on glycolytic versus tricarboxylic acid cycle intermediates
Stanislav Jabinski, Vítězslav Kučera, Marek Kopáček, Jan Jansa, and Travis B. Meador
EGUsphere, https://doi.org/10.5194/egusphere-2024-3153,https://doi.org/10.5194/egusphere-2024-3153, 2024
Short summary

Cited articles

Abernathey, R. P. and Marshall, J.: Global surface eddy diffusivities derived from satellite altimetry, J. Geophys. Res.-Oceans, 118, 901-916, https://doi.org/10.1002/jgrc.20066, 2013. 
Anderson, R. F., Fleisher, M. Q., and LeHuray, A. P.: Concentration, oxidation state, and particulate flux of uranium in the Black Sea, Geochim. Cosmochim. Ac., 53, 2215–2224, https://doi.org/10.1016/0016-7037(89)90345-1, 1989. 
Arthur, M. A., Dean, W. E., and Laarkamp, K.: Organic carbon accumulation and preservation in surface sediments on the Peru margin, Chem. Geol., 152, 273–286, https://doi.org/10.1016/S0009-2541(98)00120-X, 1998. 
Bacon, M., Cochran, J., Hirschberg, D., Hammar, T., and Fleer, A.: Export flux of carbon at the equator during the EqPac time-series cruises estimated from 234Th measurements, Deep-Sea Res. Pt. II, 43, 1133–1153, https://doi.org/10.1016/0967-0645(96)00016-1, 1996. 
Barnes, C. and Cochran, J.: Uranium removal in oceanic sediments and the oceanic U balance, Earth Planet. Sc. Lett., 97, 94–101, https://doi.org/10.1016/0012-821X(90)90101-3, 1990. 
Download
Short summary
Thorium-234 (234Th) is widely used to study carbon fluxes from the surface ocean to depth. But few studies stress the relevance of oceanic advection and diffusion on the downward 234Th fluxes in nearshore environments. Our study in offshore Peru showed strong temporal variations in both the importance of physical processes on 234Th flux estimates and the oceanic residence time of 234Th, whereas salinity-derived seawater 238U activities accounted for up to 40 % errors in 234Th flux estimates.
Share
Altmetrics
Final-revised paper
Preprint