Editing Nitrous oxide (section)

===Biological processes===
Microbial processes that generate nitrous oxide may be classified as [[nitrification]] and [[denitrification]]. Specifically, they include:

* aerobic autotrophic nitrification, the stepwise oxidation of [[ammonia]] ({{chem|NH|3}}) to [[nitrite]] ({{chem|NO|2|−}}) and to [[nitrate]] ({{chem|NO|3|−}})<!-- (Kowalchuk and Stephen, 2001)-->
* anaerobic heterotrophic denitrification, the stepwise reduction of {{chem|NO|3|−}} to {{chem|NO|2|-}}, [[nitric oxide]] (NO), {{chem|N|2|O}} and ultimately {{chem|N|2}}, where facultative anaerobe bacteria use {{chem|NO|3|−}} as an electron acceptor in the respiration of organic material in the condition of insufficient oxygen ({{chem|O|2}})<!-- (Knowles, 1982)-->
* nitrifier denitrification, which is carried out by autotrophic {{chem|NH|3}}-oxidising bacteria and the pathway whereby ammonia ({{chem|NH|3}}) is oxidised to nitrite ({{chem|NO|2|−}}), followed by the reduction of {{chem|NO|2|-}} to nitric oxide (NO), {{chem|N|2|O}} and molecular nitrogen ({{chem|N|2}})<!-- (Webster and Hopkins, 1996; Wrage et al., 2001)-->
* heterotrophic nitrification<!-- (Robertson and Kuenen, 1990)-->
* aerobic denitrification by the same heterotrophic nitrifiers<!-- (Robertson and Kuenen, 1990) -->
* fungal denitrification<!-- (Laughlin and Stevens, 2002) -->
* non-biological chemodenitrification<!-- (Chalk and Smith, 1983; Van Cleemput and Baert, 1984; Martikainen and De Boer, 1993; Daum and Schenk, 1998; Mørkved et al., 2007)-->

These processes are affected by soil chemical and physical properties such as the availability of mineral nitrogen and [[organic matter]], acidity and soil type, as well as climate-related factors such as soil temperature and water content. <!--(Mosier, 1994; Bouwman, 1996; Beauchamp, 1997; Yamulki et al. 1997; Dobbie and Smith, 2003; Smith et al. 2003; Dalal et al. 2003) -->

The emission of the gas to the atmosphere is limited greatly by its consumption inside the cells, by a process catalysed by the enzyme [[nitrous-oxide reductase|nitrous oxide reductase]].<ref>{{cite book|author1=Schneider, Lisa K. |author2=Wüst, Anja |author3=Pomowski, Anja |author4=Zhang, Lin |author5=Einsle, Oliver |chapter=No Laughing Matter: The Unmaking of the Greenhouse Gas Dinitrogen Monoxide by Nitrous Oxide Reductase |year=2014|title=The Metal-Driven Biogeochemistry of Gaseous Compounds in the Environment|pages =177–210| volume =14 |series=Metal Ions in Life Sciences |editor=Kroneck, Peter M. H. |editor2=Sosa Torres, Martha E. |publisher= Springer|doi=10.1007/978-94-017-9269-1_8|pmid=25416395|isbn=978-94-017-9268-4}}</ref>