Mercury in lake sediment cores of eastern and northern Canada
Recent and historical deposition of mercury (Hg) are examined over a broad geographic area from southwestern Northwest Territories to Labrador and from the U.S. Northeast to northern Ellesmere Island using dated sediment cores from 50 lakes (18 in midlatitudes (41-50 degrees North), 14 subarctic (51-64 degrees North) and 18 in the Arctic (65-83 degrees North)). Objectives were to quantify latitudinal and longitudinal trends of anthropogenic mercury deposition in eastern and northern North America, to investigate variations in mercury deposition, to examine relationships with lake area, catchment/lake area ratio and sedimentation rates, and to compare results with model predictions.
Distinct increases of mercury over time were observed in 76% of Arctic, 86% of subarctic and 100% of midlatitude cores. Subsurface maxima in mercury depositional fluxes were observed in only 28% of midlatitude lakes and 18% of arctic lakes, indicating little recent reduction of inputs. Anthropogenic mercury fluxes adjusted for sediment focusing and changes in sedimentation rates were negatively correlated with latitude. The latitudinal trend for anthropogenic mercury fluxes adjusted for sediment focusing and changes in sedimentation rates values showed excellent agreement with predictions of the global/regional atmospheric heavy metal (mercury) model (GRAHM) for the geographic location of each lake. The results are consistent with a scenario of slow atmospheric oxidation of mercury, and slow deposition of reactive mercury emissions, declining with increasing latitude away from emission sources in the midlatitudes, and support the view that there are significant anthropogenic mercury inputs in the Arctic.
Basic view
Metadata Record Information
- File Identifier
- 56fbf46f-2883-410c-a830-2836bcfd29f0 XML
- Date Stamp
- 2022-11-09T14:37:21
- Metadata language
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eng; CAN
- Character set
- UTF8
- Hierarchy Level
- Dataset
Data identification
- Date (Publication)
- 2018-04-30
- Date (Creation)
- 2012-02-15
- Status
- Completed
- Metadata language
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eng; CAN
- Topic category
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- Environment
- Maintenance and Update Frequency
- Not planned
- Spatial representation type
- Text, table
Keywords
- Place
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Arctic lakes
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Subarctic lakes
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Mid-latitude lakes
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Arctic
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- Theme
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Observation/Measurement
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Northern Contaminants Program (NCP)
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Mercury
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Contaminants
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Sediment cores
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Northern Ecosystem Initiative (NEI)
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Toxic Substances Research Initiative (TSRI)
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ECCC Information Category EN
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Nature and Biodiversity - Contaminants
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Government of Canada Core Subject Thesaurus
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Arctic
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Business Functions
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Assess Toxicity, Manage and Monitor for Environmental Presence of Hazardous Substances and Waste
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Monitor / Assess Substance and Waste Levels in Air, Water, Soil, Biota
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Geography
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National (CA)
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Branch
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Science and Technology Branch
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Directorate
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Water Science and Technology
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Program (PAA)
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1.2.1. Water Quality and Aquatic Ecosystems Health
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GC Security Level
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Unclassified
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- Use Limitation
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Open Government Licence - Canada ( http://open.canada.ca/en/open-government-licence-canada )
- Access Constraints
- License
- Use Constraints
- License
- Begin Date
- 1998-07-01
- End Date
- 2005-09-01
- Begin Date
- 1998-07-01
- End Date
- 2005-09-01
Extent
Ref. system Reference Systems
- Reference system identifier
- http://www.epsg-registry.org / EPSG:4326 /
Distribution
Distribution Formats
- Distribution format
-
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CSV
(
1
)
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CSV
(
1
)
https://www.canada.ca