The+Nitrogen+cycle

Why is nitrogen so important - becuase it is a constituent of proteins DNA RNA and chrolophyll. Where is most of the nitrogen is? 78% of the air is nitrogen. Nitrogen is the most common element in Earth's atmosphere, yet it is also one of the most limiting factors for growth in plants and animals. Most nitrogen exists as a gas. In this common molecule, two nitrogen atoms are bound by a strong triple bond that makes them all but completely unavailable to any other atom, ion, compound, or organism. Yet without sufficient levels of available nitrogen, organisms would be unable to create their structures or to perform vital functions. Nitrogen is a key building block in a number of important molecules, such as nucleic acids, amino acids, and proteins. Without it, life as we know it would be impossible. Organisms can only use nitrogen when it has been fixed, in a process called fixation.

Not all ammonium ions are absorved by plants, so nitrification happens. Nitrification is when the nitrate ions are absorbed by plant roots. Other bacteria converts NO3 ions into NO2.

Leaching -> Excess nitrate are washed into rivers and lakes ---> Plants life increase -> Sunlight blocked > Plants Die --->Bacteria feed of plants > Bacteria use up O2 (and no plants producing more) --> Fish die :( > EUTROPHICTION