Nitrogen fixation is a natural process that converts atmospheric nitrogen gas (N2) into a form that plants can use, such as ammonia (NH3). This process is essential because most plants cannot directly utilize nitrogen from the air. Instead, they rely on nitrogen-fixing bacteria, which can be found in the soil or in the root nodules of certain plants like legumes (peas and clover). These bacteria have special enzymes that allow them to break the strong bonds in nitrogen gas, transforming it into a usable form. Once fixed, nitrogen becomes part of the soil, enriching it and supporting plant growth, which in turn benefits the entire ecosystem.