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The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple chemical forms as it circulates among atmospheric, terrestrial, and marine ecosystems. The conversion of nitrogen can be carried out through both biological and physical processes. Important processes in the nitrogen cycle include fixation ...
Impacts of anthropogenic inputs on the nitrogen cycle. Between 1600 and 1990, global reactive nitrogen (Nr) creation had increased nearly 50%. [6] During this period, atmospheric emissions of Nr species reportedly increased 250% and deposition to marine and terrestrial ecosystems increased over 200%. [6]
Nitrogen fixation is a chemical process by which molecular dinitrogen (N. 2) is converted into ammonia (NH. 3). [1] It occurs both biologically and abiologically in chemical industries. Biological nitrogen fixation or diazotrophy is catalyzed by enzymes called nitrogenases. [2]
Nitrogen cycle. Nitrification is the biological oxidation of ammonia to nitrate via the intermediary nitrite.Nitrification is an important step in the nitrogen cycle in soil.The process of complete nitrification may occur through separate organisms [1] or entirely within one organism, as in comammox bacteria.
The Haber process, [1] also called the Haber–Bosch process, is the main industrial procedure for the production of ammonia. [2][3] It converts atmospheric nitrogen (N 2) to ammonia (NH 3) by a reaction with hydrogen (H 2) using a finely divided iron metal catalyst: This reaction is slightly favorable in terms of enthalpy, but is disfavored in ...
Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at seventh in total abundance in the Milky Way and the Solar System. At standard temperature and pressure, two atoms of the element bond to form N 2, a colorless and odorless diatomic gas.
A biogeochemical cycle, or more generally a cycle of matter, [ 1 ] is the movement and transformation of chemical elements and compounds between living organisms, the atmosphere, and the Earth's crust. Major biogeochemical cycles include the carbon cycle, the nitrogen cycle and the water cycle. In each cycle, the chemical element or molecule is ...
The nitrogen cycle is one of the Earth's biogeochemical cycles. It involves the conversion of nitrogen into different chemical forms. The main processes of the nitrogen cycle are the fixation, ammonification, nitrification, and denitrification. As one of the macronutrients, nitrogen plays an important role in plant growth.