Date of Award
Master of Science
Integrated Environmental Sciences
Mary E. Lehman, Ph.D.
Dana P. Johnson, M.S.
Heavy metals in the environment pose a risk to human health as well as to ecosystem health. These metals are released into the atmosphere as a result of industrial processes, and can be transported away from their sources to be deposited into the environment. Ectohydric mosses are known accumulators of atmospheric heavy metals, and their tissue can be used to quantify integrated deposition of these metals over time in the ecosystem.
In this study, the moss Thuidium delicatulum (Hedw.) was used to quantify lead (Pb), copper (Cu), chromium (Cr), and nickel (Ni) concentrations in the central Blue Ridge of Virginia . Projects using moss as a bioindicator of heavy metals on a landscape scale have been infrequent in the southern U.S. and have never occurred in the Blue Ridge. The objectives of the project were to evaluate the suitability of this moss for a moss-monitoring study, to assess the effects of several geographical and environmental variables on deposition, and to contribute to the current literature regarding the deposition of heavy metals in the Appalachians.
The moss was sampled on four mountains in the Blue Ridge in the Spring of 2000 following the protocol of the standard European moss-monitoring method (Markert et al. 1996). Metal concentrations in the samples of T. delicatulum corresponded with levels found in other North American and European studies.
Overall concentrations of three metals were significantly higher on one mountain, and some trends based on elevation were observed among metal concentrations in the moss sampled at all sites. A significant difference in mean metal levels, however, was observed in moss sampled under pine canopies as opposed to moss sampled under deciduous canopies. Data was standardized to account for this disparity. After reanalysis, some previous trends were altered or no longer significant, however, some new correlations emerged within the entire data set.
A lack of substrate association for metals tested and significant metal/metal correlations between Pb, Cu, and Ni suggest that the concentrations observed during this study are accurate representations of local levels of these three metals. Therefore, the applications of this method throughout the physiographic province of the Blue Ridge and the southern Appalachians in future biomonitoring are discussed.
Schilling, Johathan Scott, "BIOINDICATION OF ATMOSPHERIC HEAVY METAL DEPOSITION IN THE BLUE RIDGE USING THE MOSS THUIDIUM DELCATULUM" (2000). Theses & Honors Papers. 172.