Online ¹³C and ¹⁴C Gas Measurements by EA-IRMS–AMS at ETH Zürich

Abstract

Studies using carbon isotopes to understand the global carbon cycle are critical to identify and quantify sources, sinks, and processes and how humans may impact them. 13C and 14C are routinely measured individually; however, there is a need to develop instrumentation that can perform concurrent online analyses that can generate rich data sets conveniently and efficiently. To satisfy these requirements, we coupled an elemental analyzer to a stable isotope mass spectrometer and an accelerator mass spectrometer system fitted with a gas ion source. We first tested the system with standard materials and then reanalyzed a sediment core from the Bay of Bengal that had been analyzed for 14C by conventional methods. The system was able to produce %C, 13C, and 14C data that were accurate and precise, and suitable for the purposes of our biogeochemistry group. The system was compact and convenient and is appropriate for use in a range of fields of research.

Reconciling drainage and receiving basin signatures of the Godavari River system

“…The sample was then wrapped in tinfoil boats (Elementar), pressed, and 335 analysed using a coupled elemental analyser-isotope ratio mass spectrometer-accelerator mass spectrometer (EA-IRMS-AMS) system at ETH Zurich Wacker et al, 2010). The instrumental set-up, blank assessment, accuracy, and reproducibility for the data presented here have been previously reported in McIntyre et al (2016). 340…”

Dynamics of deep soil carbon – insights from <sup>14</sup>C time series across a climatic gradient

“…Terrestrial carbon turnover time remains one of the largest uncertainties in climate model predictions (Carvalhais et al, 2014;He et al, 2016). At present, there is no consensus on the net effect that climate and land use change will have on SOM stocks (Crowther et al, 2016;Gosheva et al, 2017;Melillo et al, 2002;Schimel et al, 2001;Trumbore and Czimczik, 2008). Deep soil carbon is of particular interest because of its large stocks (Jobbagy and Jackson, 2000;Balesdent et al, 2018;Rumpel and Kögel-Knabner, 2011) and perceived stability.…”

“…Given that the so-called "bomb radiocarbon spike" will continue to diminish in the coming decades, time-series measurements are increasingly a matter of urgency in order to take full advantage of this intrinsic tracer (Graven, 2015). Several case studies have collected time-series 14 C soil datasets and demonstrated the value of this approach (Baisden and Parfitt, 2007;Prior et al, 2007;Fröberg et al, 2010;Mills et al, 2013;Schrumpf and Kaiser, 2015). However, these studies are rare, based on single specific sites, and have been rarely linked to abiotic and biotic parameters.…”

Oceanographic and sedimentological influences on carbonate geochemistry and mineralogy in hypersaline coastal lagoons, Rio de Janeiro state, Brazil

“…Fumigated samples were analyzed on a MICADAS system (MIni CArbon DAting System) at ETH Zürich. The accelerator mass spectrometer was run in gas mode and configured to run with the elemental analyzer and the gas interface system using a method modified to incorporate a stable isotope ratio mass spectrometer (Ruff et al ; Fahrni et al ; McIntyre et al ). Radiocarbon ages were calibrated using the Marine 13 curve with the Oxcal software v 4.3.…”