Distribution of mercury in ichens across St.Charles,St.James,and St.John Parishes,Louisiana

摘要

Concentrations of mercury in the lichens Ramalina stenospora and Pamotrema Praesorediosum were determined using a Bacharach Model 50B analyzer system employing the Environmental Protection Agency(EPA) cold vapor atomic absorption method.Samples were collected from the limbs of live oak trees in a three-parish area in south-east Louisiana.The highest concentrations detected were above 0.8 ppm(#mu3g/ml) and fell off rapidly with increasing sistance from possible sources of trace metals.The spatial distribution of mercury concentrations correlated with predominant wind patterns for the region.