title: Natural and anthropogenic mercury distribution in marine sediments from Hudson Bay, Canada.
abstract: Twelve marine sediment cores from Hudson Bay, Canada, were collected to investigate the response of sub-Arctic marine sediments to atmospherically transported anthropogenic mercury (Hg). Modeling by a two-layer sediment mixing model suggests that the historical Hg deposition to most of the sediment cores reflects the known history of atmospheric Hg deposition in North America, with an onset of increasing anthropogenic Hg emissions in the late 1800s and early 1900s and a reduction of Hg deposition in the mid- to late-1900s. However, although anthropogenic Hg has contributed to a ubiquitous increase in Hg concentrations in sediments over the industrial era, the most elevated industrial-era sedimentary Hg concentrations only marginally exceed the upper preindustrial sedimentary Hg concentrations. Analysis of delta13C and relationship between Hg and organic matter capture suggests that the response of Hudson Bay sediments to changes in atmospheric Hg emissions is largely controlled by the particle flux in the system and that natural changes in organic matter composition and dynamics can cause variation in sedimentary Hg concentrations at least to the same extent as those caused by increasing anthropogenic Hg emissions.
authors.affiliation: Centre for Earth Observation Science, Department of Environment and Geography, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2.
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Hare
authors.forename: Gary A
authors.initials: GA
authors.lastname: Stern
authors.forename: Zou Zou A
authors.initials: ZZ
authors.lastname: Kuzyk
authors.forename: Robie W
authors.initials: RW
authors.lastname: Macdonald
authors.forename: Sophia C
authors.initials: SC
authors.lastname: Johannessen
authors.forename: Feiyue
authors.initials: F
authors.lastname: Wang
mesh_terms: D002170:Canada; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D008628:Mercury / Q000032:analysis*; D012623:Seawater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014877:Water Pollution, Chemical / Q000706:statistics & numerical data
chemical_list: D014874:Water Pollutants, Chemical; D008628:Mercury