Biogeochemical processes accounting for the natural mercury variations in the Southern Ocean diatom ooze sediments
Due to its toxic nature and its high potential for biomagnification, mercury is a pollutant of concern. Understanding the marine biogeochemical cycle of mercury is crucial as consumption of mercury-enriched marine fish is the most important pathway of human exposure to monomethylmercury, a neurotoxi...
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ftdoajarticles:oai:doaj.org/article:1c2308e45d8e43a8ad9399a05b111529 2023-05-15T13:40:15+02:00 Biogeochemical processes accounting for the natural mercury variations in the Southern Ocean diatom ooze sediments S. Zaferani H. Biester 2020-06-01T00:00:00Z https://doi.org/10.5194/os-16-729-2020 https://doaj.org/article/1c2308e45d8e43a8ad9399a05b111529 EN eng Copernicus Publications https://os.copernicus.org/articles/16/729/2020/os-16-729-2020.pdf https://doaj.org/toc/1812-0784 https://doaj.org/toc/1812-0792 doi:10.5194/os-16-729-2020 1812-0784 1812-0792 https://doaj.org/article/1c2308e45d8e43a8ad9399a05b111529 Ocean Science, Vol 16, Pp 729-741 (2020) Geography. Anthropology. Recreation G Environmental sciences GE1-350 article 2020 ftdoajarticles https://doi.org/10.5194/os-16-729-2020 2022-12-31T03:45:36Z Due to its toxic nature and its high potential for biomagnification, mercury is a pollutant of concern. Understanding the marine biogeochemical cycle of mercury is crucial as consumption of mercury-enriched marine fish is the most important pathway of human exposure to monomethylmercury, a neurotoxin. However, due to the lack of long-term marine records, the role of the oceans in the global mercury cycle is poorly understood. We do not have well-documented data of natural mercury accumulations during changing environmental conditions, e.g., sea surface conditions in the ocean. To understand the influence of different sea surface conditions (climate-induced changes in ice coverage and biological production) on natural mercury accumulation, we used a continuous ∼170 m Holocene biogenic sedimentary record from Adélie Basin, East Antarctica, which mainly consists of silica-based skeletons of diatoms. We performed principal component analysis and regression analysis on element concentrations and corresponding residuals, respectively, to investigate the link between sediment mercury accumulation, terrestrial inputs, and phytoplankton productivity. Preindustrial mercury in the remote marine basin shows extremely high accumulation rates (median: 556 µ g m −2 yr −1 ) that displayed periodic-like variations. Our analyses show that the variations in total mercury concentrations and accumulation rates are associated with biological production and related scavenging of water-phase mercury by rapidly sinking algae or algae-derived organic matter after intense algae blooms. High accumulation rates of other major and trace elements further reveal that, in regions of high primary productivity, settling of biogenic materials removes a large fraction of dissolved or particulate-bound elements from the free water phase through scavenging or biological uptake. The link between mercury cycling and primary production will need to be considered in future studies of the marine mercury cycle under primary production enhancement through ... Article in Journal/Newspaper Antarc* Antarctica East Antarctica Southern Ocean Directory of Open Access Journals: DOAJ Articles Southern Ocean East Antarctica Ocean Science 16 3 729 741 |
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language |
English |
topic |
Geography. Anthropology. Recreation G Environmental sciences GE1-350 |
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Geography. Anthropology. Recreation G Environmental sciences GE1-350 S. Zaferani H. Biester Biogeochemical processes accounting for the natural mercury variations in the Southern Ocean diatom ooze sediments |
topic_facet |
Geography. Anthropology. Recreation G Environmental sciences GE1-350 |
description |
Due to its toxic nature and its high potential for biomagnification, mercury is a pollutant of concern. Understanding the marine biogeochemical cycle of mercury is crucial as consumption of mercury-enriched marine fish is the most important pathway of human exposure to monomethylmercury, a neurotoxin. However, due to the lack of long-term marine records, the role of the oceans in the global mercury cycle is poorly understood. We do not have well-documented data of natural mercury accumulations during changing environmental conditions, e.g., sea surface conditions in the ocean. To understand the influence of different sea surface conditions (climate-induced changes in ice coverage and biological production) on natural mercury accumulation, we used a continuous ∼170 m Holocene biogenic sedimentary record from Adélie Basin, East Antarctica, which mainly consists of silica-based skeletons of diatoms. We performed principal component analysis and regression analysis on element concentrations and corresponding residuals, respectively, to investigate the link between sediment mercury accumulation, terrestrial inputs, and phytoplankton productivity. Preindustrial mercury in the remote marine basin shows extremely high accumulation rates (median: 556 µ g m −2 yr −1 ) that displayed periodic-like variations. Our analyses show that the variations in total mercury concentrations and accumulation rates are associated with biological production and related scavenging of water-phase mercury by rapidly sinking algae or algae-derived organic matter after intense algae blooms. High accumulation rates of other major and trace elements further reveal that, in regions of high primary productivity, settling of biogenic materials removes a large fraction of dissolved or particulate-bound elements from the free water phase through scavenging or biological uptake. The link between mercury cycling and primary production will need to be considered in future studies of the marine mercury cycle under primary production enhancement through ... |
format |
Article in Journal/Newspaper |
author |
S. Zaferani H. Biester |
author_facet |
S. Zaferani H. Biester |
author_sort |
S. Zaferani |
title |
Biogeochemical processes accounting for the natural mercury variations in the Southern Ocean diatom ooze sediments |
title_short |
Biogeochemical processes accounting for the natural mercury variations in the Southern Ocean diatom ooze sediments |
title_full |
Biogeochemical processes accounting for the natural mercury variations in the Southern Ocean diatom ooze sediments |
title_fullStr |
Biogeochemical processes accounting for the natural mercury variations in the Southern Ocean diatom ooze sediments |
title_full_unstemmed |
Biogeochemical processes accounting for the natural mercury variations in the Southern Ocean diatom ooze sediments |
title_sort |
biogeochemical processes accounting for the natural mercury variations in the southern ocean diatom ooze sediments |
publisher |
Copernicus Publications |
publishDate |
2020 |
url |
https://doi.org/10.5194/os-16-729-2020 https://doaj.org/article/1c2308e45d8e43a8ad9399a05b111529 |
geographic |
Southern Ocean East Antarctica |
geographic_facet |
Southern Ocean East Antarctica |
genre |
Antarc* Antarctica East Antarctica Southern Ocean |
genre_facet |
Antarc* Antarctica East Antarctica Southern Ocean |
op_source |
Ocean Science, Vol 16, Pp 729-741 (2020) |
op_relation |
https://os.copernicus.org/articles/16/729/2020/os-16-729-2020.pdf https://doaj.org/toc/1812-0784 https://doaj.org/toc/1812-0792 doi:10.5194/os-16-729-2020 1812-0784 1812-0792 https://doaj.org/article/1c2308e45d8e43a8ad9399a05b111529 |
op_doi |
https://doi.org/10.5194/os-16-729-2020 |
container_title |
Ocean Science |
container_volume |
16 |
container_issue |
3 |
container_start_page |
729 |
op_container_end_page |
741 |
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1766131520244809728 |