Use of the mercury record in Red Tarn sediments to reveal air pollution history and the implications of catchment erosion.

摘要: Red Tarn is a cirque lake with small ratio of terrestrial area to area, surrounded by glacial edges little soil in the catchment. A sediment core taken from deepest was 210Pb dated and validated 137Cs 241Am stratigraphic records. The analysed for mercury (Hg) other elements. results show Hg pollution before mid-19th century, thereafter, rapid increase into modern time, followed decline since 1968–1970. This agrees well UK emissions Clear Air Act 1968. suggest that has recorded air history, it can be used benchmark changes sediments lakes region up late 1980s. However, increased fluxes after 1980s indicate enhanced catchment erosion, which brought more legacy lake. As consequence, 2000, record no longer reflects atmospheric deposition. shows how dominant sources changed deposition inputs, demonstrates contaminated inputs have not only but also concentrations sediments.