The Nitrogen Cycle 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. …
showed first 75 words of 701 total

showed last 75 words of 701 total
…systems, the added nitrogen can lead to eutrophication. *Increased deposition of nitrogen from atmospheric sources because of fossil fuel combustion and forest burning. Both of these processes release a variety of solid forms of nitrogen through combustion. *Livestock ranching. Livestock release a large amounts of ammonia into the environment from their wastes. This nitrogen enters the soil system and then the hydrologic system through leaching, groundwater flow, and runoff. *Sewage waste and septic tank leaching.