The validity of the use of sycamore tree rings for the reconstruction of atmospheric lead pollution histories was investigated. The lead concentration and <sup>206</sup>Pb/<sup>207</sup>Pb profiles of several tree cores collected from the Loch Lomond region were compared with one another and with the established records at a Loch Lomond sediment core and as Scottish archival moss collection. Little similarity was observed among the lead concentration and isotopic histories of the tree cores, or between the records of the tree-cores and the sediment/moss records. Sycamore tree ring analysis was also used to investigate the temporal and spatial influence of lead pollution from two areas of former lead mining and smelting. Wanlockhead and Tyndrum, which produced lead with distinctive isotopic signatures. The investigation of lead concentrations and <sup>206</sup>Pb/<sup>207</sup>Pb ratios revealed a waning influence of the mines with both distance and time since cessation of operations. Although general temporal trends of lead pollution in regions close to large point sources were identified in the tree-ring studies, accurate annual records were not preserved. The contemporary concentration and isotopic composition of atmospheric lead in Scotland was investigated by the analysis of tree bark. Some 85 samples of Scots pine tree bark were collected from throughout mainland Scotland and analysed for lead concentrations and isotopic ratios. The lead concentrations in bark allowed comparison of the relative atmospheric lead concentrations around the country, with higher lead concentration observed in areas of higher population and traffic density, and lower concentrations associated with more remote areas. The <sup>206</sup>Pb/<sup>207</sup>Pb ratios allowed estimations of the source/s of the lead detected in the tree bark. Tree bark was seen to be less suitable for studies of contemporary atmospheric isotopic composition than moss.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:660431 |
| Date | January 2004 |
| Creators | Patrick, Gavin James |
| Publisher | University of Edinburgh |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/1842/15595 |
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