Recent lead deposition trends in the Czech Republic as recorded by peat bogs and tree rings

The lead (Pb) content and 206Pb/207Pb ratio were studied in three peat profiles dated by 210Pb from the border-area mountains of the Czech Republic and in the tree rings of spruce trees located in their immediate vicinity. Both archives document a similar progress in Pb pollution levels and Pb accumulation in the 1950’s–1990’s. The deposition rate (DR) of Pb in peat bogs attained maximum values of 40 mg Pb m−2 y−1 in the “Black Triangle” area and 15 mg Pb m−2 y−1 in more distant areas in this period. The Pb isotopic record of both archives from the contaminated area exhibit a similar trend in the presence of the individual sources of Pb, in which Pb derived from combustion of coal predominates. The peat cores in more distant areas document well the effect of automobile Pb in the atmosphere and its substantial reduction after 2000. The two archives differ in individual patterns following from the differences in the rates of formation of their biomass and different means of deposition of Pb in the two archives.