Peat bogs in northern Alberta, Canada reveal decades of declining atmospheric Pb contamination



Shotyk, William, Appleby, Peter G ORCID: 0000-0002-6945-1841, Bicalho, Beatriz, Davies, Lauren, Froese, Duane, Grant-Weaver, Iain, Krachler, Michael, Magnan, Gabriel, Mullan-Boudreau, Gillian, Noernberg, Tommy
et al (show 4 more authors) (2016) Peat bogs in northern Alberta, Canada reveal decades of declining atmospheric Pb contamination. GEOPHYSICAL RESEARCH LETTERS, 43 (18). pp. 9964-9974.

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Abstract

<jats:title>Abstract</jats:title><jats:p>Peat cores were collected from six bogs in northern Alberta to reconstruct changes in the atmospheric deposition of Pb, a valuable tracer of human activities. In each profile, the maximum Pb enrichment is found well below the surface. Radiometric age dating using three independent approaches (<jats:sup>14</jats:sup>C measurements of plant macrofossils combined with the atmospheric bomb pulse curve, plus <jats:sup>210</jats:sup>Pb confirmed using the fallout radionuclides <jats:sup>137</jats:sup>Cs and <jats:sup>241</jats:sup>Am) showed that Pb contamination has been in decline for decades. Today, the surface layers of these bogs are comparable in composition to the “cleanest” peat samples ever found in the Northern Hemisphere, from a Swiss bog ~ 6000 to 9000 years old. The lack of contemporary Pb contamination in the Alberta bogs is testimony to successful international efforts of the past decades to reduce anthropogenic emissions of this potentially toxic metal to the atmosphere.</jats:p>

Item Type: Article
Depositing User: Symplectic Admin
Date Deposited: 28 Sep 2016 08:02
Last Modified: 18 Sep 2023 23:40
DOI: 10.1002/2016GL070952
Related URLs:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3003485