Accumulation rates and predominant atmospheric sources of natural and anthropogenic Hg and Pb on the Faroe Islands ...

• Main Authors: Van Der Knaap, Pim, Heinemeier, J., Lohse, C., Norton, S.A., Givelet, N., Cheburkin, A.K., Roos-Barraclough, F., Le Roux, G., Weiss, D., Shotyk, W., Goodsite, M.E., Knudsen, K.
• Format: Text
• Language: English
• Published: Elsevier Science 2005
• Subjects: 580 Plants Botany; Faroe Islands; Greenland
• Online Access: https://dx.doi.org/10.7892/boris.73965; http://boris.unibe.ch/73965/

A monolith representing 5420 14C yr of peat accumulation was collected from a blanket bog at Myrarnar, Faroe Islands. The maximum Hg concentration (498 ng/g at a depth of 4.5 cm) coincides with the maximum concentration of anthropogenic Pb (111 μg/g). Age dating of recent peat accumulation using 210Pb (CRS model) shows that the maxima in Hg and Pb concentrations occur at AD 1954 ± 2. These results, combined with the isotopic composition of Pb in that sample (206Pb/207Pb = 1.1720 ± 0.0017), suggest that coal burning was the dominant source of both elements. From the onset of peat accumulation (ca. 4286 BC) until AD 1385, the ratios Hg/Br and Hg/Se were constant (2.2 ± 0.5 × 10-4 and 8.5 ± 1.8 × 10-3, respectively). Since then, Hg/Br and Hg/Se values have increased, also reaching their maxima in AD 1954. The age date of the maximum concentrations of anthropogenic Hg and Pb in the Faroe Islands is consistent with a previous study of peat cores from Greenland and Denmark (dated using the atmospheric bomb pulse ...