What is the primary outcome of the process known as nitrification?

Nitrification is a crucial process in the nitrogen cycle, primarily involving the conversion of ammonia (NH3) into nitrates (NO3-). This two-step microbial process is facilitated by specific bacteria. First, ammonia is oxidized into nitrites (NO2-) by bacteria such as Nitrosomonas. Then, another group of bacteria, including Nitrobacter, further oxidizes nitrites into nitrates.

This conversion is vital for several reasons. Nitrates are more readily absorbed by plants, making them an essential form of nitrogen for plant growth. Without nitrification, the availability of nitrogen in a form that plants can utilize would be significantly reduced, affecting entire ecosystems.

In contrast, the other processes listed do not accurately represent nitrification. Converting plant matter into soil relates to decomposition, the breakdown of nitrogen compounds into gas is associated with denitrification, and the synthesis of nitrogen compounds by plants refers to nitrogen fixation. Thus, the primary outcome of nitrification is indeed the conversion of ammonia to nitrates, making it a key part of nutrient cycling in ecosystems.