carbon dioxide + water + light energy → carbohydrate + oxygen
Even if the single oxygen per carbon stayed buried, we'd lose a maximum of 400ppm[1] of oxygen, of currently 20.95 % volume of oxygen. That does not even affect the last digit of that rounded number, and the number is normally not given with more digits because it changes with the season and stuff.
No carbon dioxide in the atmosphere would probably be really bad for further tree growth (among other things), so it is naturally limited.
n CO2 + n H2O + photons → (CH2O)n + n O2
carbon dioxide + water + light energy → carbohydrate + oxygen
Even if the single oxygen per carbon stayed buried, we'd lose a maximum of 400ppm[1] of oxygen, of currently 20.95 % volume of oxygen. That does not even affect the last digit of that rounded number, and the number is normally not given with more digits because it changes with the season and stuff.
No carbon dioxide in the atmosphere would probably be really bad for further tree growth (among other things), so it is naturally limited.
[1]http://www.esrl.noaa.gov/gmd/ccgg/trends/#mlo