The nitrogen cycle represents one of the most important nutrient cycles found in terrestrial ecosystems (Figure 1). Nitrogen is used by living organisms to produce a number of complex organic molecules like amino acids, proteins, and nucleic acids. The largest store of nitrogen is found in the atmosphere where it exists as a gas (mainly N2). The atmospheric store is about one million times larger than the total nitrogen contained in living organisms. Other major stores of nitrogen include organic matter in soil and the oceans.…
