Which process is crucial for converting atmospheric nitrogen into a usable form for plants?

Nitrification is a crucial process for converting atmospheric nitrogen into a form that plants can use, specifically nitrates. This process occurs in two main steps: first, ammonia (which can come from the decomposition of organic matter) is oxidized into nitrites by bacteria, and then those nitrites are further oxidized into nitrates by another group of bacteria. The nitrates produced through this process are the form of nitrogen that plants can absorb through their roots and utilize to synthesize proteins and other essential compounds.

The importance of nitrification in the nitrogen cycle cannot be understated. While nitrogen gas (N2) makes up a significant portion of the Earth's atmosphere, it is not directly usable by most organisms. Nitrification thus serves as a vital link in making nitrogen available in a bioavailable form necessary for plant growth.