Atmospheric Nitrogen is NOT bioavailable.
Nitrogen fixation
Furthermore... water has a max rate of O2 holding dependent on temp and pressure... You will simply raise the level to the max by this method making it easier for all O2 using organisms to have less competition for the available O2. Not sure how this will play out with the non-aerobic stuff.
Using this science can anyone explain why plants go off after an electrical storm? I always assumed it was from the lightning charging the water with nitrogen?