200 years of Pb deposition throughout the Czech Republic: Patterns and sources.
Historical rates of Pb deposition were determined over the past 150-200 years for eight sites throughout the Czech Republic using Pb-210-dated, Sphagnum-derived peat cores. Maximum historical Ph deposition was greater at sites in the northern and western parts of the Czech Republic than at sites in the southern part of the Czech Republic (peak values averaging 57, 21, and 16 mg m(-2) yr(-1), respectively). Lead deposition patterns generally reflect increasing industrialization over the past 100-200 years, especially in the post-We rid War II era. For seven of the eight sites, maximum Pb deposition occurred between 1965 and 1992, corresponding to a period of peak production and burning of lignite coal. A decrease in Ph deposition rates since 1975-1980 was evident in seven of the sites. The most recent Pb deposition rates (1992), estimated from the uppermost peat core sections, averaged 32, 11, and 7 mg m(-2) yr(-1) for the northern, western, and southern sites, respectively, are higher than current Pb deposition in the eastern United States of 4 mg m(-2) yr(-1). Lead deposition rates prior to Czech industrialization, estimated from the deepest dateable peat core sections, averaged 8, 5, and 1 mg m(-2) yr(-1) for the northern, western, and southern sites, respectively. Using acid-insoluble ash concentrations in peat and peat magnetic susceptibility determinations, we were able to identify past periods of elevated Pb deposition related to local mining of Pb-containing ore deposits at three of the sites and periods of elevated Pb deposition from fossil fuel combustion at five of the sites. Without stable Pb isotopic determinations, the importance of lead ed gasoline-derived Ph could not be determined.
|Main Author:||Vile, Melanie.|
|Other Authors:||Wieder, R Kelman., Novak, Martin.|