Regional and Local Variations in Heavy Metal Concentrations of Bryophytes in the Northeastern United States
1976; Wiley; Volume: 27; Issue: 3 Linguagem: Inglês
10.2307/3543463
ISSN1600-0706
Autores Tópico(s)Peatlands and Wetlands Ecology
ResumoWide regional variations in the deposition of air-borne heavy metals in the northeastern USA were determined by analyzing Leucobryum glaucum (Hedw.) Angstr. ex Fr., and other mosses collected throughout the region for Pb, Cu, Cd, Cr, Ni, and Zn. Lead, Cu, Cr, and Ni concentrations were generally highest in the southern, more highly industrialized portions of New England. A trend of decreasing concentrations with increasing distance from New York City was found for all metals except Cd. Cadmium and Zn concentrations tended to increase with increasing altitude. Except for Zn, the average concentrations of all metals in samples from the northeastern USA were considerably higher than the near-natural levels found in samples from remote areas of Canada, suggesting that high levels of air-borne heavy metals are present in the atmosphere of the northeast. Based on Leucobryum glaucum data, metal deposition rates were determined for various areas within the northeastern USA. Average annual deposition rates for the northeast were 32.9 ? 2.3 mg Pb m-2, 2.4 ? 0.2 mg Cu m-2, 0.19 ? 0.01 mg Cd m-2, 13.5 ? 0.7 mg Zn m-2, 1.3 ? 0.1 mg Cr m-2, and 2.3 ? 0.2 mg Ni m-2.
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