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
> 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
> 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
Keeling, R., and Shertz, S. 1992. Seasonal and interannual variations in
atmospheric oxygen and implications for the global carbon cycle. Nature
Keeling, R., and Najjar, R. 1993. What atmospheric oxygen measurements
can tell us about the global carbon cycle. Global Biogeochemical Cycles
Hope this helps!
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.)