SC4730 Environmental Science
Analysis 2
Nitrogen cycle
Nitrogen exists in nature in many different forms, from molecular nitrogen in gaseous to the complex organic compounds in the body of plants, animals and humans. In an organism, Nitrogen exists in the form of organic compounds such as proteins, amino acids. When the microorganisms die, the amount of nitrogen exists in soil. Under the action of the group saprophytic microorganisms, proteins are degraded to amino acids. The amino acid to be a group of other microorganisms into NH3 or NH4+ called ammonium group of bacteria. This process called mineralization of organic matter such as through organic nitrogen is converted into nitrogen mineralization types. NH4 + form will be converted into the form of NO3- by nitrifying bacteria. (Wikipedia, Nitrogen cycle) Of the nitrate compounds are converted into nitrogen molecules, this process is called nitrification reaction was carried out by reaction of nitrate bacteria. N2 gas will be fixed in bacterial cells and plant cells are then transformed into organic forms of nitrogen by microorganisms group of fixed nitrogen. (Wikipedia, Nitrogen cycle) Thus nitrogen cycle is closed in most phases of the cycle metabolism and involvement of different groups of microorganisms. If the activities of a group are stopped the whole metabolism of the cycle will be seriously affected.

The process of ammonium
The organic forms of nitrogen converted to NH3 or NH4 +. a / The chemical urea ammonium: the process of urea ammonium divided into two stages:
Stage 1: Under the action of urease enzyme secreted by microorganisms, the urea decomposes to form ammonium carbonate salt.
2(NH4)CO ⎯⎯⎯→ CO(NH2)2 + 2H2O
Stage 2: Ammonium carbonate is converted to (NH4) 2CO3 but it isn’t (NH4)2CO3 durable so liberated NH3, CO2 and H2O.
CO(NH2)2 ⎯⎯⎯→ (NH4)2CO3 ⎯⎯⎯→ 2NH3 + CO2 + H2O
Also in urine