Alexander L. Friend wrote:
>> Is anyone else bothered by the mis-use of the photosynthetic gas exchange
> phenomenon to imply that deforestation will threaten our oxygen
supply? If
> so, have you seen or written anything accessible to college sophomores on
> the subject?
>> In my class, Forest Ecology and the Global Environment, many of my students
> have come across this in the popular literature.
I've had the same points come up in my intro Ecology class. I use the
same argument you use: oxygen is ~20% of the atmosphere and CO2 is
0.036%. However, I do point out that there would be no O2 if it wasn't
for photosynthesis, but the buildup of O2 occurred over millions of
years.
> Literature citations would be especially welcome as I am trying to upgrade
> my reading list for the fall.
Here are some old and recent articles that might help:
Dole, M., Lane, G.A., Rudd, D.P., and Zaukelies, D.A. 1954. Isotopic
composition of atmospheric oxygen and nitrogen. Geochim Cosmochim Acta
6: 65-78.
Keeling, R., and Shertz, S. 1992. Seasonal and interannual variations in
atmospheric oxygen and implications for the global carbon cycle. Nature
358: 723-727.
Keeling, R., and Najjar, R. 1993. What atmospheric oxygen measurements
can tell us about the global carbon cycle. Global Biogeochemical Cycles
7: 37-67.
Hope this helps!
Renee
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_____________________________________________________________
J. Renee Brooks jrbrooks at chuma.cas.usf.edu
Department of Biology (813) 974-7352 (Office)
University of South Florida (813) 974-3263 (FAX)
Tampa, FL 33620-5150 (813) 974-3250 (Dept.)
http://www.cas.usf.edu/biology/brooks.html
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