Low sedimentary accumulation of lead caused by weak downward export of organic matter in Hudson Bay, northern Canada
Atmospheric input of anthropogenic lead increased globally over the last centuries. The present study shows that the concentrations of lead in sediment cores from low-productivity Hudson Bay, northern Canada, remained relatively constant over the last centuries. The lack of imprint of the increased...
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ftird:oai:ird.fr:fdi:010071392 2024-09-15T18:11:00+00:00 Low sedimentary accumulation of lead caused by weak downward export of organic matter in Hudson Bay, northern Canada Thibodeau, B. Migon, C. Dufour, A. Poirier, A. /Mari, Xavier Ghaleb, B. Legendre, L. CANADA HUDSON BAIE 2017 https://www.documentation.ird.fr/hor/fdi:010071392 EN eng https://www.documentation.ird.fr/hor/fdi:010071392 oai:ird.fr:fdi:010071392 Thibodeau B., Migon C., Dufour A., Poirier A., Mari Xavier, Ghaleb B., Legendre L. Low sedimentary accumulation of lead caused by weak downward export of organic matter in Hudson Bay, northern Canada. 2017, 136 (3), p. 279-291 Vertical transfer Particulate matter Oligotrophy Ocean Climate change Carbon budget text 2017 ftird 2024-08-15T05:57:41Z Atmospheric input of anthropogenic lead increased globally over the last centuries. The present study shows that the concentrations of lead in sediment cores from low-productivity Hudson Bay, northern Canada, remained relatively constant over the last centuries. The lack of imprint of the increased anthropogenic lead input in this marine environment is not consistent with the increased lead concentrations in nearby lakes over the same period. In addition, the observed trend in lead isotopic composition in our cores suggests an apparent progressive overprint of anthropogenic lead during the 1900s. In other words, isotopes clearly registered the increasingly anthropogenic nature of lead in the sedimentary record, but total lead concentrations remained constant, indicating that some process limited the export of lead to the sediment. These observations point to a long-term limitation of the downward export of particles in Hudson Bay. Given that the source of lead was the same for both Hudson Bay and neighboring high-productivity lakes, we hypothesize that the very low primary productivity of Hudson Bay waters was responsible for the low vertical export of lead to marine sediments. We further propose that primary productivity is the most important factor that generally drives the vertical export of particulate matter, and thus hydrophobic contaminants, in near-oligotrophic marine environments. Text Hudson Bay IRD (Institute de recherche pour le développement): Horizon |
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IRD (Institute de recherche pour le développement): Horizon |
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language |
English |
topic |
Vertical transfer Particulate matter Oligotrophy Ocean Climate change Carbon budget |
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Vertical transfer Particulate matter Oligotrophy Ocean Climate change Carbon budget Thibodeau, B. Migon, C. Dufour, A. Poirier, A. /Mari, Xavier Ghaleb, B. Legendre, L. Low sedimentary accumulation of lead caused by weak downward export of organic matter in Hudson Bay, northern Canada |
topic_facet |
Vertical transfer Particulate matter Oligotrophy Ocean Climate change Carbon budget |
description |
Atmospheric input of anthropogenic lead increased globally over the last centuries. The present study shows that the concentrations of lead in sediment cores from low-productivity Hudson Bay, northern Canada, remained relatively constant over the last centuries. The lack of imprint of the increased anthropogenic lead input in this marine environment is not consistent with the increased lead concentrations in nearby lakes over the same period. In addition, the observed trend in lead isotopic composition in our cores suggests an apparent progressive overprint of anthropogenic lead during the 1900s. In other words, isotopes clearly registered the increasingly anthropogenic nature of lead in the sedimentary record, but total lead concentrations remained constant, indicating that some process limited the export of lead to the sediment. These observations point to a long-term limitation of the downward export of particles in Hudson Bay. Given that the source of lead was the same for both Hudson Bay and neighboring high-productivity lakes, we hypothesize that the very low primary productivity of Hudson Bay waters was responsible for the low vertical export of lead to marine sediments. We further propose that primary productivity is the most important factor that generally drives the vertical export of particulate matter, and thus hydrophobic contaminants, in near-oligotrophic marine environments. |
format |
Text |
author |
Thibodeau, B. Migon, C. Dufour, A. Poirier, A. /Mari, Xavier Ghaleb, B. Legendre, L. |
author_facet |
Thibodeau, B. Migon, C. Dufour, A. Poirier, A. /Mari, Xavier Ghaleb, B. Legendre, L. |
author_sort |
Thibodeau, B. |
title |
Low sedimentary accumulation of lead caused by weak downward export of organic matter in Hudson Bay, northern Canada |
title_short |
Low sedimentary accumulation of lead caused by weak downward export of organic matter in Hudson Bay, northern Canada |
title_full |
Low sedimentary accumulation of lead caused by weak downward export of organic matter in Hudson Bay, northern Canada |
title_fullStr |
Low sedimentary accumulation of lead caused by weak downward export of organic matter in Hudson Bay, northern Canada |
title_full_unstemmed |
Low sedimentary accumulation of lead caused by weak downward export of organic matter in Hudson Bay, northern Canada |
title_sort |
low sedimentary accumulation of lead caused by weak downward export of organic matter in hudson bay, northern canada |
publishDate |
2017 |
url |
https://www.documentation.ird.fr/hor/fdi:010071392 |
op_coverage |
CANADA HUDSON BAIE |
genre |
Hudson Bay |
genre_facet |
Hudson Bay |
op_relation |
https://www.documentation.ird.fr/hor/fdi:010071392 oai:ird.fr:fdi:010071392 Thibodeau B., Migon C., Dufour A., Poirier A., Mari Xavier, Ghaleb B., Legendre L. Low sedimentary accumulation of lead caused by weak downward export of organic matter in Hudson Bay, northern Canada. 2017, 136 (3), p. 279-291 |
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1810448598180036608 |