Which process describes the conversion of ammonia to nitrite and nitrate in aquatic systems?

Which process describes the conversion of ammonia to nitrite and nitrate in aquatic systems?

• A. Carbon cycle
• B. Oxygen cycle
• C. Hydrogen cycle
• D. Nitrogen cycle

Answer: (D)

Nitrification is the transformation of ammonia to nitrite and then to nitrate, a key part of the nitrogen cycle in aquatic systems. In aerated water, ammonia from waste or decay is oxidized to nitrite by ammonia-oxidizing bacteria, and nitrite is further oxidized to nitrate by nitrite-oxidizing bacteria. This two-step process detoxifies ammonia and makes nitrogen available in forms that plants or denitrifying microbes can use or remove. Carbon cycle, oxygen cycle, and hydrogen cycle describe other elemental processes and do not describe this ammonia-to-nitrite-to-nitrate sequence.

Nitrification is the transformation of ammonia to nitrite and then to nitrate, a key part of the nitrogen cycle in aquatic systems. In aerated water, ammonia from waste or decay is oxidized to nitrite by ammonia-oxidizing bacteria, and nitrite is further oxidized to nitrate by nitrite-oxidizing bacteria. This two-step process detoxifies ammonia and makes nitrogen available in forms that plants or denitrifying microbes can use or remove. Carbon cycle, oxygen cycle, and hydrogen cycle describe other elemental processes and do not describe this ammonia-to-nitrite-to-nitrate sequence.