The earth’s atmosphere is made up of approximately 78% nitrogen gas, making it the most plentiful element in the atmosphere. It stands to reason therefore that it must be critically important to life on earth. Nitrogen is found in DNA, amino acids, proteins, and more. Nitrogen is also needed by plants to make chlorophyll that is then used to make food for the plant. Nitrogen from the atmosphere changes from one chemical form to other forms as it moves from the atmosphere to the land and back to the atmosphere.
For example, nitrogen gas from the atmosphere forms nitrogen oxides when lightening breaks the strong nitrogen molecule bonds. The nitrogen oxides then combine with oxygen to form nitrates that dissolve in rain and fall to the earth. Fixation, decay, nitrification and denitrification processes help to cycle the nitrogen back into the atmosphere.