The accuracy of mercury (Hg) dendrochemistry has been questioned because significant knowledge gaps exist in understanding the Hg translocation and mobility in tree-ring. In this study, we evaluated Hg concentrations and isotopic profiles in the tree-ring at a Hg artisanal mining site and a control site with the documented local Hg production inventory. Results show that the Hg concentration accumulated in tree-ring fails to reconstruct the temporal trend of Hg production due to confounded tree physiological and environmental factors, specifically, the radial translocation and tree age effects occurring during the fast-growing period. The temporal profiles of delta 202Hg exhibit pronounced tree-specific variabilities due to the complexity of Hg isotopic mass dependent fractionation during atmospheric Hg uptake and translocation in vegetation. The Hg odd-MIF (mass independent fractionation) profiles in tree-ring can reconstruct a decadal-scale temporal trend of the atmospheric Hg0 pollution level, and also be used as a tracer to distinguish the emission source shifts of atmospheric Hg0. However, the radial translocation would result in uncertainties at the higher resolution because of the mixing of odd-MIF signatures with active rings. Caution should be taken and additional supporting evidence collected from independent methods should be used for verifying the tree-ring records.
Publication name |
JOURNAL OF HAZARDOUS MATERIALS Volume: 415 Article Number: 125678 DOI: 10.1016/j.jhazmat.2021.125678 Published: AUG 5 2021 |
Author(s) |
Wang, Xun; Yuan, Wei; Lin, Che-Jen; Wu, Fei; Feng, Xinbin |
Corresponding author(s) |
WANG Xun1,2; FENG Xinbin1,3 wangxun@mail.gyig.ac.cn;fengxinbin@vip.skleg.cn 1. Chinese Acad Sci, Inst Geochem, State Key Lab Environm Geochem, Lincheng Rd 99, Guiyang 550081, Guizhou, Peoples R China 2. Southwest Univ, Coll Resources & Environm, Chongqing 400715, Peoples R China 3. Chinese Acad Sci, Ctr Excellence Quaternary Sci & Global Change, Xian 710061, Peoples R China | View here for the details
|
|
|