Bacteria in nitrogen cycle
...produced by decay is converted into nitrites by bacteria of the genus Nitrosomonas. Then bacteria of the genus Nitrobacter oxidize the nitrites to nitrates. Denitrification is the reduction of nitrates to nitrogen gas by denitrifying bacteria. The bacteria like Pseudomonas, convert nitrites into molecular nitrogen. However, some of the nitrite is converted by bacteria into nitrous oxide and released into the air. Nitrogen Fixation is the incorporation of nitrogen gas into organic nitrogen-containing compounds. Nitrogen-fixing bacteria convert nitrogen gas into ammonium compounds, which can be used to synthesize other biological compounds. An example of nitrogen-fixing bacteria is Rhizobium. The plants don't use ammonia directly, but it's a product of the waste. (Bill Indge, November 2000) There are a number of benefits of bacteria in nitrogen cycle. The organic nitrogen compounds such as nitrates is used by living organisms to produce a number of complex organic molecules like amino acids, proteins, and nucleic acids. It produce organic nitrogen compounds which promote the growth of the plants. Nitrogen-fixing cyanobacteria are essential to maintaining the fertility of semi-aquatic environments like rice paddies. After the nutrients in the soil are used up by plants, it will restore the fertility of the soil. The increased use of legumes offers the potential for a significant decrease in the need for fertilizer nitrogen, and therefore is a key component of sustainable agricultural systems. It increases yields in the fields, and also when it reduces, or at least does not increase the risk like the problem cause by the fertilizer. Example, the blue-green alga Anabaena and the water fern Azolla pinnata sown on the rice field produce a crop-yield increase of 50 to 100%.Besides that, it also reduce the concentration of ammonia, which is toxic to fishes and aqua life by convert ammonia into nitrites and then to nitrates. (The Nitrogen Cycle, http://www.mi.mun.ca/mi-net/enviro/enviro1.htm#assi) However, there are also disadvantages of bacteria in nitrogen cycle. Biological nitrogen fixation requires a complex set of enzymes, nitroge...