The major sources of oxygen...are plants because without them we wouldn't have enough oxygen to start with..
plants
Plants provide oxygen water has oxygen in it idk if theirs anything else
The two main sources for obtaining oxygen are the air - 23% of air is oxygen - and water by electrolysis.
air water trees
Ozone is a tri oxygen molecule. It is formed by the action of UV light on oxygen.
leaking oxygen cylinders and liquid oxygen systems in the immediate area
gas liquid air(oxygen)
Water, Oxygen, Wind, Sun...
Wind and rain
One can find medical oxygen solutions from the following sources: Health Oxygen, Portable Oxygen, Oxygen Solutions, Alternative Oxygen Solutions, to name a few.
Oxygen is important as it the breathing sources. It also forms ozone which is vital for life on earth.
Air pollution is virtually anything that isn't nitrogen, oxygen or water vapor. It can come from natural sources or human sources.