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 have even seen forest
products companies use the oxygen producing benefits of trees for PR
purposes. My best argument has been that since the atmospheric pool is
more than 500x greater for oxygen than CO2, impacts of photosynthetic
activity (or a lack thereof) on atmospheric oxygen concentration are
trivial relative to their effects on atmospheric CO2 concentration. My
intuition is that deforestation, or other reductions of global carbon
fixing potential, whould have to be catastrophic in nature to threaten our
oxygen supply, but I have not attempted any calculations or considered the
sensitivity of ecosystems (via fire), or organisms, to small changes in
atmospheric oxygen concentration.
Are there any better arguments, or differences of opinion, on this one?
Literature citations would be especially welcome as I am trying to upgrade
my reading list for the fall.
Thanks --Alex
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| Alexander L. Friend | Assoc. Professor of Forest Ecophysiology
| Box 9681 | Forest and Wildlife Research Center,
| Department of Forestry | Mississippi State University
