ROCR 01 Peirce Mill

Rock Creek Park

Previous studies

In 1982, lichen studies in ROCR were conducted by David Schwartzman and students at Howard University (Kasim et al. 1982, Schwartzman et al. 1987, 1991). They found evidence for elevated Pb and Cd in various lichens collected near Peirce Mill. ROCR 01 was established nearby to provide a basis for comparison with results from these previous studies.

Site data

38.9469N 77.0477W

Oak-hickory forest

Corticololous lichens in plot 2004 (abundance)

Flavoparmelia caperata (2)

Myelochroa aurulenta (3)
Phaeophyscia pusilloides (1)
Phaeophyscia rubropulchra (2)

Physcia millegrana (2)

Punctelia rudecta (3)

Pyxine caesiopruinosa (1)
Pyxine sorediata (2)

Element data (mean µg/g ± SD)

2004	2009
Cd  < 0.54 Cu  14.20 ± 0.63 Cr   2.28 ± 0.21 Pb  27.03 ± 3.30 Ni   1.98 ± 0.35 Zn  41.92 ± 0.15 S  1557.8 ± 47.6 Hg  0.14 ± 0.02	Cd  < 0.50 Cu  15.02 ± 1.57 Cr   2.83 ± 1.05 Pb  19.59 ± 1.58 Ni   2.69 ± 0.28 Zn  55.52 ± 2.77 S  1599.2 ± 27.47 Hg  —