STEP 3b: View Example Graph
This graph was prepared by a marine biologist, and looks much like the
graphs you'll prepare as you complete this project. Below is the comparison
of rockweed cover at middle elevation unoiled sites
and oiled/washed rocky sites, 1989-1996. Washed sites were cleaned by
hot-water washing during the months after the spill.
Mean Percent Cover of a 0.25 Square meter Quadrat
Summary of Fucus gardneri Abundance
This graph shows mean percent Fucus gardneri cover of 0.25
square meter quadrat from 1989 to 1996. Abundance is plotted for these
categories: oiled/washed and unoiled. The data for oiled/washed sites
show a steep decline
in cover in 1989 after treatment. Mean abundance of oiled/washed Fucus dropped from a high of 80% cover per quadrat in 1989 to a low of less
than 5% in
1990. Abundance then steadily increased to a high of over 60% in 1993.
Cover
again declined, reaching a low of about 20% in 1995, then increasing
to about
35% in 1996.
The abundance of unoiled Fucus fluctuated somewhat during
the
same period, but gradually decreased from about 70% cover per quadrat
in 1989
to just over 30% in 1996. Although the steep decline in Fucus cover
in 1989 at
oiled/washed sites almost certainly reflects the impact of oil and
treatment, the
other fluctuations are more difficult to explain. This is true for
oiled/washed sites,
as well as control sites.
Proceed
to Step 4a: Interpret Your Data and Write Report
(Top)
