Nitrogen Cycle

We intervene in the nitrogen cycle in several ways that affect what goes on in the atmosphere and in aquatic systems. We add large amounds of nitrogen oxides to the atmosphere when we burn gasoline and other fuels and when we use commercial nitrate ferilizers. For example, we add nitric oxide (NO) into the atmosphere when N2 and O2 combine as we burn any fuel at high temperatures, such as in car, truck, and jet engines. In the atmosphere, this gas can be converted to nitrogen dioxide gas (NO2) and nitric acid vapor (HNO3), which can return to the earth's surface as damaging acid deposition, commonly called acid rain.