Nitrogen cycle

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The nitrogen cycle is the process by which nitrogen is converted between its various chemical forms. This transformation can be carried out through both biological and physical processes. Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and denitrification. The majority of Earth's atmosphere (78%) is nitrogen,[1] making it the largest pool of nitrogen. However, atmospheric nitrogen has limited availability for biological use, leading to a scarcity of usable nitrogen in many types of ecosystems. The nitrogen cycle is of particular interest to ecologists because nitrogen availability can affect the rate of key ecosystem processes, including primary production and decomposition. Human activities such as fossil fuel combustion, use of artificial nitrogen fertilizers, and release of nitrogen in wastewater have dramatically altered the global nitrogen cycle[citation needed].

A 2011 study found that nitrogen from rocks may also be a significant source of nitrogen, that had not previously been included in most calculations and statistics.
Nitrogen is essential for many processes and is crucial for any life on Earth. It is a component in all amino acids, as incorporated into proteins, and is present in the bases that make up nucleic acids, such as RNA and DNA. In plants, much of the nitrogen is used in chlorophyll molecules, which are essential for photosynthesis and further growth.[5] Although Earth's atmosphere is an abundant source of nitrogen, most is relatively unusable by plants.[6] Chemical processing, or natural fixation (through processes such as bacterial conversion—see rhizome), are necessary to convert gaseous nitrogen into forms usable by living organisms, which makes nitrogen a crucial component of food production. The abundance or scarcity of this "fixed" form of nitrogen, (also known as reactive nitrogen), dictates how much food can be grown on a piece of land. The nitrogen cycle and the carbon cycle work together to maintain an ecosystem. Source of the article published in description is Wikipedia. I am sharing their material. Copyright by original content developers of Wikipedia.
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