Nitrogen Cycle (APES)

Ammonification

plants die→decompose→convert to NH3 and NH4

Nitrogen Fixation

Links the atmosphere part to the terrestrial part, plants cannot use the N2 gas in the atmosphere

N2+3H2→2NH3

Assimilation

The process where plants and animals take up nitrogen compounds like nitrates from the soil to build proteins and other essential molecules for growth and development.

NH3, NH4, NO3 used in plant production

Nitrification

Gas to ammonia. The process where bacteria convert ammonia into nitrites, then into nitrates.

NH3→NO2→NO3

Dentrification

The process where bacteria convert nitrates in the soil back into nitrogen gas, releasing it back into the atmosphere.

NH3 and NH4 → NO2 and NO3 → N2; links terrestrial back to the atmospheric part