The type of bacteria that are essential for nitrogen fixation are known as rhizobia. These bacteria form symbiotic relationships with the roots of leguminous plants, converting atmospheric nitrogen (N₂) into ammonia (NH₃), which plants can use for growth. This process enriches the soil with usable nitrogen and plays a critical role in the nitrogen cycle. Nitrogen fixation is essential for agriculture, as it enhances soil fertility and reduces the need for synthetic fertilizers. Understanding the role of rhizobia is crucial for sustainable farming practices and ecosystem management.