Why Is Oxygen Important in Water?

Oxygen

• The most common element on earth is oxygen, which is present in both water and ozone. Oxygen readily forms compounds with other elements and dissolves when air and water come into contact, although it is less soluble at higher temperatures.

Oxygen and Water

• All living plants and animals on the planet require oxygen in order to breathe. Fish breathe by absorbing the oxygen gas from water with their gills. Human beings cannot breathe underwater because their lungs lack the surface area to absorb oxygen in this way. Without oxygen, fish and other organisms in water would be unable to survive.

Environmental Issues

• Micro-organisms use oxygen to decompose organic matter in water, thus keeping the equilibrium of the environment constant. An issue with global warming is that increased temperatures cause a lessening of oxygen in the water of the earth's lakes, oceans and streams.