What a biotic factor can fix nitrogen?

A biotic factor that can fix nitrogen is certain bacteria, particularly those in the genus Rhizobium. These bacteria form symbiotic relationships with leguminous plants, where they inhabit root nodules and convert atmospheric nitrogen into a form that plants can use for growth. This process, known as nitrogen fixation, is crucial for maintaining soil fertility and supporting plant health. Other nitrogen-fixing organisms include free-living bacteria like Azotobacter and cyanobacteria.