Nitrogen Cycle Essay

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The Nitrogen Cycle or Nitric Acid? Discuss the relevance of these to the debate between intensive and organic farming. In the farming industry the nitrogen cycle is important. Whether it is organic or intensive farming the best way to a high crop yield is to add fertiliser full of nitrogen and other elements to help the plants grow. Artificial fertilisers and organic fertilisers both have advantages and disadvantages to their usage in farming. Either way both are used to enhance the nitrogen cycle for a better crop yield. Nitrogen is necessary for all life on Earth and is an important component in plant and animal cells. Organisms need nitrogen to produce proteins, nucleic acids, and amino acids. While nitrogen gas (mostly N2) makes up 78% of the Earth’s atmosphere, it is not usable in that form by most plants and animals (1). Most living things can only use nitrogen when combined with carbon, hydrogen, or oxygen. The nitrogen cycle describes the way in which microorganisms transform atmospheric nitrogen and the nitrogen contained in organic matter into usable compounds (2). The steps of the nitrogen cycle are: nitrogen fixation, assimilation, ammonification, nitrification, dentrification, and anaerobic ammonium oxidation. The nitrogen cycle begins with atmospheric nitrogen. To be useful to plant and animal life, non reactive elemental nitrogen (N2) must be combined (or “fixed”) with hydrogen to form ammonium (NH4) ions or with oxygen (NO3) to form nitrate ions. Microorganisms in the Earth’s soil convert nitrogen into ammonia by using an enzyme called nitrogenase (3). This process is called “nitrogen fixation” and the microorganisms that accomplish it include free-living bacteria, such as Azotobacter, Purple sulphur bacteria, some Cyanobacteria, as well as bacteria that live symbiotically with plants. Plants can use either ammonium or nitrate, which
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