APES 1.5 Nitrogen Cycle

Nitrogen Cycle

• Most abundant gas in the atmosphere
• A somewhat inert gas, doesn't react much
• The nitrogen cycle plays an important role in the "life" of ecosystems
• Nitrogen is a common limiting factor for producers due to its high required amounts for some processes
• Used to form amino acids and nucleic acids (very important)

Breakdown of cycle:

Nitrogen fixation

• Converts N2 from atmosphere
• Biotic processes convert N2 to ammonia (NH3)
• abiotic converts it to nitrate (NO3)

Assimilation

• Producers take up ammonium (NH4+) or nitrate (NO3-)
• Consumers assimilate nitrogen by eating said producers

Ammonification

• Decomposers break down biological nitrogen compounds into ammonium (NH4+)

Nitrification

• Nitrifying bacteria convert ammonium (NH4+) into nitrite (NO2-)
• And then into nitrate (NO3-)

Denitrification

• Denitrifying bacteria in soil with low oxygen or stagnant water convert nitrate (NO3-) into nitrous oxide (N2O)
• And eventually nitrogen gas (N2)