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A synthesis of mercury research in the Southern Hemisphere, part 2: Anthropogenic perturbations.

ABSTRACT: Environmental mercury (Hg) contamination is a global concern requiring action at national scales. Scientific understanding and regulatory policies are underpinned by global extrapolation of Northern Hemisphere Hg data, despite historical, political, and socioeconomic differences between the hemispheres that impact Hg sources and sinks. In this paper, we explore the primary anthropogenic perturbations to Hg emission and mobilization processes that differ between hemispheres and synthesize current understanding of the implications for Hg cycling. In the Southern Hemisphere (SH), lower historical production of Hg and other metals implies lower present-day legacy emissions, but the extent of the difference remains uncertain. More use of fire and higher deforestation rates drive re-mobilization of terrestrial Hg, while also removing vegetation that would otherwise provide a sink for atmospheric Hg. Prevalent Hg use in artisanal and small-scale gold mining is a dominant source of Hg inputs to the environment in tropical regions. Meanwhile, coal-fired power stations continue to be a significant Hg emission source and industrial production of non-ferrous metals is a large and growing contributor. Major uncertainties remain, hindering scientific understanding and effective policy formulation, and we argue for an urgent need to prioritize research activities in under-sampled regions of the SH.

SUBMITTER: Fisher JA

PROVIDER: S-EPMC10073395 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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A synthesis of mercury research in the Southern Hemisphere, part 2: Anthropogenic perturbations.

Fisher Jenny A JA Schneider Larissa L Fostier Anne-Hélène AH Guerrero Saul S Guimarães Jean Remy Davée JRD Labuschagne Casper C Leaner Joy J JJ Martin Lynwill G LG Mason Robert P RP Somerset Vernon V Walters Chavon C

Ambio 20230323 5

Environmental mercury (Hg) contamination is a global concern requiring action at national scales. Scientific understanding and regulatory policies are underpinned by global extrapolation of Northern Hemisphere Hg data, despite historical, political, and socioeconomic differences between the hemispheres that impact Hg sources and sinks. In this paper, we explore the primary anthropogenic perturbations to Hg emission and mobilization processes that differ between hemispheres and synthesize current ...[more]

PMID: 36952094

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A synthesis of mercury research in the Southern Hemisphere, part 2: Anthropogenic perturbations.

Publications

A synthesis of mercury research in the Southern Hemisphere, part 2: Anthropogenic perturbations.

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