The largest pool of nitrogen on Earth is found in our atmosphere. Nitrogen is one of the most abundant substances in the atmosphere, and makes up about 78% of the air we breathe. It is essential for life on Earth and is a component of all proteins, DNA, and other important molecules.
Nitrogen is also found in many other places on the planet. It can be found in the soil, water, and even in the ocean. However, the largest pool of nitrogen on Earth is found in the atmosphere. This nitrogen is constantly being cycled between the atmosphere, land, and ocean.
When nitrogen is released into the atmosphere, it is mainly in the form of nitrogen dioxide (NO2). This gas is released as a result of combustion, such as from car exhaust and burning fossil fuels. Nitrogen dioxide is one of the major contributors to air pollution.
The nitrogen dioxide in the atmosphere is then broken down by sunlight, producing nitric oxide (NO). This gas is then converted into nitrate (NO3-) and nitrite (NO2-) molecules, which are the main forms of nitrogen that plants and animals need.
Nitrogen is also released into the atmosphere from natural sources such as lightning and wildfires. This nitrogen is then taken up by plants, which then use it to build proteins and other molecules that are essential for life on Earth.
The amount of nitrogen in the atmosphere is constantly being cycled, and it is estimated that about 78% of the Earth's nitrogen is found in the atmosphere. This is the largest pool of nitrogen on Earth, and it is essential for all life on our planet.