Nitrogen fixation is the process by which nitrogen gas from the atmosphere is converted into ammonia or other molecules that plants can use. In soil, nitrogen fixation can be carried out by certain types of bacteria such as Rhizobium and Azotobacter. These bacteria have the enzyme nitrogenase that allows them to convert atmospheric nitrogen (N2) into ammonia (NH3) or nitrate (NO3-), which can then be used by plants to make proteins and other essential compounds. This process helps in replenishing the soil with usable nitrogen, which is necessary for plant growth and overall ecosystem health.
