Increased atmospheric deposition of mercury in reference lakes near major urban areas

P. C. Van Metre

doi:10.1016/j.envpol.2011.11.003

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Increased atmospheric deposition of mercury in reference lakes near major urban areas

P. C. Van Metre

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Abstract

Atmospheric deposition of Hg is the predominant pathway for Hg to reach sensitive ecosystems, but the importance of emissions on near-field deposition remains unclear. To better understand spatial variability in Hg deposition, mercury concentrations were analyzed in sediment cores from 12 lakes with undeveloped watersheds near to (<50 km) and remote from (>150 km) several major urban areas in the United States. Background and focusing corrected Hg fluxes and flux ratios (modern to background) in the near-urban lakes (68 ± 6.9 μg m −2 yr −1 and 9.8 ± 4.8, respectively) greatly exceed those in the remote lakes (14 ± 9.3 μg m −2 yr −1 and 3.5 ± 1.0) and the fluxes are strongly related to distance from the nearest major urban area ( r 2 = 0.87) and to population and Hg emissions within 50–100 km of the lakes. Comparison to monitored wet deposition suggests that dry deposition is a major contributor of Hg to lakes near major urban areas.

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Environmental Pollution Article

Source-reported bounding extent: 17.94655° to 71.35776° latitude; -171.79111° to -65.591° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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P. C. Van Metre. 2012. Increased atmospheric deposition of mercury in reference lakes near major urban areas. https://doi.org/10.1016/j.envpol.2011.11.003

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