|
|
|
|
|
Study methods |
|
Site Location
§
Permanent study sites (presently 102 total) were established in
nine NCR park units: §
CATO §
CHOH §
GWMP §
HAFE §
MANA §
NACE §
NAMA §
PRWI §
ROCR §
Sites were placed in forested locations where a sample of one
lichen species (Flavoparmelia caperata) could be obtained for elemental
analysis. §
In CATO and PRWI sites were located within 1 km2 grids. §
A 20m X 20m quadrat was established at each site and its GPS
location recorded. Site data (abundance scores)
§
The sampling protocol was similar to that of McCune et al.
(1997) used in the Forest Health Monitoring Program (complete details of the
methods are given in Tallent-Halsell,1994); the only difference is that a
plot of 20m X 20m was used instead of a circular plot of 36.6 m radius. §
Within each quadrat presence of all corticolous
(bark-inhabiting) macrolichen species was recorded; species on dead and down
trees were included. §
Terricolous (ground-dwellling) species and corticolous species
below 0.5 m on trees were included as off-frame information. §
Sensitivity
to pollution was assess for species based on a literature survey. §
The abundance of all lichen species was also recorded
using abundance scores from McCune et al. (1997): 1
= rare (< 3 individuals in plot) Sampling for elemental analysis
§
A sample of a single lichen (F. caperata) was obtained in each
plot for elemental analysis. This species has been used in several previous
biomonitoring studies done in the NCR. §
Lichen samples were analyzed for metals (Cd,Cu,Pb,Ni,Cr,Zn, EPA
method 3051), total sulfur (3051 digest), and Hg (EPA method 7471). §
Seven park units (CATO, CHOH, GWMP, NACE, NAMA, PRWI, ROCR) were sampled in 2004; HAFE and MANA were sampled in
2006. All park units were resampled in 2009. . |
NCR Lichens Home Location of NCR park
units
Flavoparmelia caperata
used
in elemental analyses. Image © 2006 by Paul Diederich from http://www.lichenology.info. |
