Written Assignment: Biology and Technology in the Real World
Background: This assignment will give you the opportunity to participate in ongoing scientific research. For the past several years, I have been involved in ecological research in old-growth forests in Wisconsin. In many areas the forest floor is dominated by a grasslike species, Pennsylvania sedge (Carex pensylvanica). The sedge may exclude other ground species by interspecific competition, which may decrease the number of species in an area, which is a main component of biodiversity. The Penn sedge "lawns" are probably caused by selective herbivory by an abundance of white-tailed deer. The deer do not like the sedge but consume most other ground plants.
Another problem in the forests is that dominant trees, such as white pine and sugar maple, do not show successful reproduction to replace the old pines and maples that die, which leads to the question - does Pennsylvania sedge decrease the establishment of tree seedlings? With support from a UMUC Faculty Research Grant to create this assignment, I collected data last summer that you can use to test three hypotheses-
Hypotheses
A. Pennsylvania sedge inhibits regeneration of white pine
B. Pennsylvania sedge inhibits regeneration of sugar maple
C. Pennsylvania sedge decreases biodiversity
REPORT
Your report should be organized under the following bold headings (or a similar format).
Background - Choice of Study Site
I use GPS readings of latitude and longitude for reports on my study sites, so others may be able to locate them. The Trout Lake Point study plot for this Penn sedge project was approximately centered at 46o 02' 45.00" N latitude and 89o 40' 07.25" W longitude. It extended south to north about 43.0" to 47.0" and east to west about 6.0" to 8.5".
Please use Google Earth to locate the study plot (coordinates of latitude and longitude should be in the lower right corner of the Google Earth screen). The current aerial photograph on Google Earth was taken on May 9, 2013. Note the ice on Trout Lake, as it was a late spring. Note that the deciduous trees (maples, oaks, etc.) have yet to leaf, while the pines and other conifers are green. Look over the study site and its surroundings by navigating with the GPS coordinates given above and describe (1) the forest of the peninsula in general from what you can see from the aerial perspective and (2) why you think the study plot was not extended farther south or farther north within the peninsula.
Hypotheses
Simply restate the 3 hypotheses here.
[Normally a scientific report would next have a section on methods, but you can skip this since I already stated the methods in the assignment.]
Results
Here, report on your analysis of the data. Include tables and/or graphs and text to explain them. [Graphing reminder - best to put independent variable on x-axis and dependent variable on y-axis.]
Conclusions & Discussion
Summarize your analyses by concluding whether the data support or disprove Hypotheses A, B, and C. Then discuss how your conclusions might relate to the many factors that influence forest composition. For example, one factor not measured that may affect our data is the amount of shade. Although the study area had similar tree composition throughout, some areas contained thicker shade, which might decrease both sedge cover and species richness, thus obscuring any relationship between the two. Ecology is very complex, that's why it is so much fun (but it makes it very difficult to verify causes and effects). Again, be creative in the discussion. Shade is just one example of many factors that influence plant growth.
One experiment leads to another in the scientific method. In your discussion, use your conclusions to generate at least one new hypothesis that could be tested to further add to our knowledge of the effects of Pennsylvania sedge.