Year: 2024
Type: article
Abstract: High Resolution Image Download MS PowerPoint Slide Tree rings are an emerging atmospheric mercury (Hg) archive. Questions have arisen, though, regarding their mechanistic controls and reliability. Here, we report contrasting tree-ring Hg records in three collocated conifer species: Norway spruce ( Picea abies ), Scots pine ( Pinus sylvestris ), and European larch ( Larix decidua ), which are from a remote boreal forest. Centennial atmospheric Hg trends at the site, derived from varved lake sediments, peats, and atmospheric monitoring, indicated a steady rise from the 1800s, peaking in the 1970s, and then declining. Prior to ca. 2005, larch and spruce tree rings reproduced the peak in the atmospheric Hg trend, while pine tree rings peaked in the 1930s, likely due to the prolonged sapwood period and ambiguity in the heartwood–sapwood boundary of pine. Since ca. 2005, tree rings from all species showed increasing Hg concentrations in the physiologically active outer rings despite declining atmospheric Hg concentrations. The good agreement between Hg and nitrogen concentrations in active tree-ring cells indicates a similar transport mechanism and cautions against their applicability as atmospheric Hg archives. Our results suggest that tree-ring Hg records are controlled by atmospheric Hg and tree physiology. We provide recommendations for using tree-ring Hg archives that take tree physiology into account.
Authors: Haijun Peng, Xiangwen Zhang, Kevin Bishop, John Marshall, Mats B. Nilsson, Chuxian Li, Erik Björn, Wei Zhu
Language: English
Subfield: Health, Toxicology and Mutagenesis
Field: Environmental Science
Domain: Physical Sciences
SDG: Climate action
Open Access status: hybrid
Estimated APC paid: $4,500
Awards: G2529142191, G3972297889, Magnitude and drivers of legacy mercury emission from contaminated pulp-fiber sediments: Towards a refined risk assessment by accounting for emission to the atmosphere, Magnitude and Drivers of Mercury Exchange between the Atmosphere and the Boreal Forest: A Multidisciplinary Approach to Decipher the Role of the Boreal Forest in the Global Mercury Cycle, Does European anthropogenic mercury emission reduction benefit the recovery of biota from mercury pollution in the Baltic Sea? A perspective for fulfilling the Minamata Convention
OpenAlex ID: W4402350511