Element cycles nitrogen cycle

The cyclical movement of elements between living organisms (the biotic phase) and their nonliving (abiotic) surroundings (e.g. rocks, water, air). Examples of biogeochemical cycles are the carbon cycle, nitrogen cycle, oxygen cycle, phosphorus cycle, and sul-phur cycle. 

One of the things that environmental scientists do IS to keep track of important elements in the biosphere—in what form do these ele ments normally occur to what are they transformed and how are they returned to their normal state Careful studies have given clear although compli cated pictures of the nitrogen cycle the sulfur cy cle and the phosphorus cycle for example The carbon cycle begins and ends with atmospheric carbon dioxide It can be represented in an abbrevi ated form as... 

The following sections summarize only the most prominent interactions between the elemental cycles and the links in the hydrologic cycle. Water also plays a role in many chemical and biological reactions that are beyond the scope of this discussion. The carbon, nitrogen, sulfur, and phosphorus cycles are discussed in detail in Chapters 11, 12, 13, and 14, respectively. 

No element is ever destroyed by use. The radioactive ones decay, but stable elements may be used over and over. The nitrogen cycle shows how the nitrogen atoms in your body and the ones in the air have been combining and recombining for millions of years. 

Rodin, L. E., Bazilevich, N. I. (1965). The dynamics of Organic Matter and Biological Cycling of Ash Elements and Nitrogen in Major Vegetation Type of the Earth. Moscow-Leningrad Nauka Publishing House, 321 pp. 

The most noteworthy multistage element cycles in which bacteria play important roles are the nitrogen and sulfur redox cycles. The fixation of nitrogen is a reductive process that provides organisms with nitrogen in a form usable for the synthesis of amino acids, nucleic acids, and other cell constituents. In essence, the overall conversion to the key intermediate, ammonia, can be represented as ... 

The nitrogen cycle is closely connected with the fluxes of hydrogen, sulfur, and other chemicals (Smith et al., 1998 Dimitroulopoulou and Marsh, 1997 Chapin et al., 2002 Rhee et al., 2005 Stevenson and Cole, 1999). Nitrogen and hydrogen react under great pressure and temperature in the presence of a catalyst to make ammonia. The study of correlations between the cycles of these elements is necessary to improve... 

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