Under natural conditions, the amount of nitrogen gas returned to the atmosphere by denitrification approximately equals
A) phosphorus cycling.
B) evaporation.
C) nitrogen fixation.
D) sublimation.
E) photosynthesis.

Question

Quizplus · Accepted Answer

Denitrification and nitrogen fixation are both parts of the nitrogen cycle, where nitrogen is converted between its various chemical forms. Denitrification returns nitrogen gas to the atmosphere, while nitrogen fixation converts atmospheric nitrogen into forms usable by living organisms. Under natural conditions, these processes are balanced.

Under Natural Conditions, the Amount of Nitrogen Gas Returned to the Atmosphere