TWO PARMOTREMA LICHEN SPECIES AS POLLUTION BIOINDICATORS IN FLORIDA

Lichens are commonly used as bioindicators of air pollution. For my thesis, I tested the utility of two easily identified lichen species as bioindicators. Parmotrema perforatum is considered to be pollution intolerant, while Parmotrema subrigidium is considered to be somewhat pollution tolerant. I surveyed P. perforatum and P. subrigidum growing on the trunks of southern live oak trees (Quercus virginiana) at two sites on the John D. MacArthur campus of Florida Atlantic University in Jupiter, Florida that differed in exposure to road traffic. One site on the interior of campus (AOS1) was distant from any road, while the other site (AOS2) was along a busy road. I identified lichen samples from using keys and chemical spot tests. I found AOS1 had a higher density of P. perforatum, and whereas AOS2 had a higher density of P. subrigidum, confirming the utility of these two lichens as bioindicators of pollution.