Which process is directly involved in converting ammonia to nitrate?

Nitrification is the process that converts ammonia (NH3) into nitrate (NO3-) through a two-step oxidation process. During the first step, ammonia is oxidized to nitrite (NO2-) by specific bacteria, such as Nitrosomonas. In the second step, nitrite is further oxidized to nitrate by another group of bacteria, including Nitrobacter. This process is a crucial part of the nitrogen cycle, as it transforms ammonia, which can be toxic at high concentrations, into nitrate, a form that is much more readily taken up by plants.

This process is significant for soil health and plant nutrition, as nitrate serves as an essential nutrient for plant growth. The transformation from ammonia to nitrate enables the ecosystem to utilize nitrogen more effectively, supporting various life forms.

Ammonification is related but involves the conversion of organic nitrogen (from decomposing plant and animal matter) into ammonia, not directly into nitrate. Fixation refers to the process of converting atmospheric nitrogen into a form that living organisms can use, often into ammonia. Denitrification is the process where nitrate is reduced back to nitrogen gas (N2), completing the nitrogen cycle but not converting ammonia to nitrate. Therefore, nitrification is the correct choice for the conversion