Atmospheric Mercury Accumulation Rates Between 5900 and 800 Calibrated Years BP in the High Arctic of Canada Recorded by Peat Hummocks

详细信息    查看全文

• 作者：Nicolas Givelet ; Fiona Roos-Barraclough ; Michael E. Goodsite ; Andriy K. Cheburkin ; and William Shotyk
• 刊名：Environmental Science & Technology
• 出版年：2004
• 出版时间：October 1, 2004
• 年：2004
• 卷：38
• 期：19
• 页码：4964 - 4972
• 全文大小：223K
• 年卷期：v.38,no.19(October 1, 2004)
• ISSN：1520-5851

文摘

In this paper, we present the first comprehensive long-term record of preanthropogenic rates of atmospheric mercuryaccumulation in dated peat deposits for the High Arcticof Canada. Geochemical studies of two peat hummocks fromBathurst Island, Nunavut reveal substantial inputs fromsoil dust (titanium), marine aerosols (bromine), and mineral-water interactions (uranium). Mercury, however, wassupplied to these peat mounds exclusively by atmosphericdeposition. Mercury concentration measurements andage dating of the peat profiles indicate rather constantnatural "background" mercury flux of ca. 1 microgram persquare meter per year from 5900 to 800 calibrated yearsBP. These values are well within the range of the mercuryfluxes reported from other Arctic locations, but also bypeat cores from southern Canada that provide a record ofatmospheric Hg accumulation extending back 8000years. Thus, preanthropogenic Hg fluxes in the Arcticwere not significantly different from atmospheric Hg fluxesin the temperate zone. In preindustrial times, therefore,the High Arctic was no more important as a sink for globalatmospheric mercury than was the temperate zone.