This article includes a list of general references, but it lacks sufficient corresponding inline citations. Please help to improve this article by introducing more precise citations.(August 2014) (Learn how and when to remove this message)
Eutrophication, which is often caused by overabundance of reactive nitrogen, is apparent as increased turbidity in the northern part of the Caspian Sea, imaged from orbit.
Reactive nitrogen ("Nr"), also known as fixed nitrogen[1], refers to all forms of nitrogen present in the environment except for molecular nitrogen (N 2).[2] While nitrogen is an essential element for life on Earth, molecular nitrogen is comparatively unreactive, and must be converted to other chemical forms via nitrogen fixation before it can be used for growth. Common Nr species include nitrogen oxides (NO x), ammonia (NH 3), nitrous oxide (N 2O), as well as the anion nitrate (NO− 3).
Biologically, nitrogen is "fixed" mainly by the microbes (eg., Bacteria and Archaea) of the soil that fix N 2 into mainly NH 3 but also other species. Legumes, a type of plant in the Fabacae family, are symbionts to some of these microbes that fix N 2. NH 3 is a building block to Amino acids and proteins amongst other things essential for life. However, just over half of all reactive nitrogen entering the biosphere is attributable to anthropogenic activity such as industrial fertilizer production.[3] While reactive nitrogen is eventually converted back into molecular nitrogen via denitrification, an excess of reactive nitrogen can lead to problems such as eutrophication in marine ecosystems.
A schematic representing the marine nitrogen cycle.
^Winiwarter, Wilfried; Erisman, Jan Willem; Galloway, James N.; Klimont, Zbigniew; Sutton, Mark A. (25 July 2013). "Estimating environmentally relevant fixed nitrogen demand in the 21st century" (PDF). Climatic Change. 120 (4): 889–901. Bibcode:2013ClCh..120..889W. doi:10.1007/s10584-013-0834-0. eISSN 1573-1480. ISSN 0165-0009. S2CID 51862713.
^Galloway, James N.; Leach, Allison M.; Bleeker, Albert; Erisman, Jan Willem (5 July 2013). "A chronology of human understanding of the nitrogen cycle". Philosophical Transactions of the Royal Society B: Biological Sciences. 368 (1621): 20130120. doi:10.1098/rstb.2013.0120. eISSN 1471-2970. ISSN 0962-8436. PMC 3682740. PMID 23713118.
^Fowler, David; Coyle, Mhairi; Skiba, Ute; Sutton, Mark A.; Cape, J. Neil; Reis, Stefan; Sheppard, Lucy J.; Jenkins, Alan; Grizzetti, Bruna; Galloway, James N.; Vitousek, Peter; Leach, Allison; Bouwman, Alexander F.; Butterbach-Bahl, Klaus; Dentener, Frank; Stevenson, David; Amann, Marcus; Voss, Maren (5 July 2013). "The global nitrogen cycle in the twenty-first century". Philosophical Transactions of the Royal Society B: Biological Sciences. 368 (1621): 20130164. doi:10.1098/rstb.2013.0164. eISSN 1471-2970. ISSN 0962-8436. PMC 3682748. PMID 23713126.
Reactivenitrogen ("Nr"), also known as fixed nitrogen, refers to all forms of nitrogen present in the environment except for molecular nitrogen (N 2)...
Reactivenitrogen species (RNS) are a family of antimicrobial molecules derived from nitric oxide (•NO) and superoxide (O2•−) produced via the enzymatic...
atmospheric reactivenitrogen (Nr) fluxes. Agricultural sources of reactivenitrogen can produce atmospheric emission of ammonia (NH3), nitrogen oxides (NO...
leaks. Atomic nitrogen, also known as active nitrogen, is highly reactive, being a triradical with three unpaired electrons. Free nitrogen atoms easily...
Nitrogen dioxide is a chemical compound with the formula NO2. One of several nitrogen oxides, nitrogen dioxide is a reddish-brown gas. It is a paramagnetic...
of nitrogen fertilizer, which was used at a rate of about 110 million tons (of N) per year in 2012, adding to the already existing amount of reactive nitrogen...
be utilized in most biological processes, N2 must be converted to reactivenitrogen (Nr), which includes inorganic reduced forms (NH3 and NH4+), inorganic...
subtropical thunderstorms studied turned 7 kg (15 lb) of nitrogen into chemically reactive NOx. With 1.4 billion lightning flashes per year, multiplied...
to as sewage dumping, and still occurs all over the world. Excess reactivenitrogen compounds in the environment are associated with many large-scale...
to the generated reactive free radicals. There are 3 main pathways for the generation of reactive oxygen species or reactivenitrogen species (RNS) in...
to as sewage dumping, and still occurs all over the world. Excess reactivenitrogen compounds in the environment are associated with many large-scale...
stress Oxygen toxicity Pro-oxidant Reactivenitrogen species Reactive sulfur species Reactive carbonyl species Reactive oxygen species production in marine...
phagosome. The bacteria also evades macrophage-killing by neutralizing reactivenitrogen intermediates. More recently, M. tuberculosis has been shown to secrete...
the systemic manifestation of reactive oxygen species and a biological system's ability to readily detoxify the reactive intermediates or to repair the...
of human impact on the nitrogen cycle. In the Netherlands, the soil is burdened by a very high deposition of reactivenitrogen compounds, in particular...
cells, causing cellular damage or even toxicity. Reactivenitrogen signaling, coupled with reactive oxygen species, have been found to be a central part...
contributors to a buildup of reactivenitrogen in the biosphere, causing an anthropogenic disruption to the nitrogen cycle. Since nitrogen use efficiency is typically...
directly neutralizes various reactive oxygen species, including hydroxyl (OH•), superoxide (O2−•), and reactivenitrogen species such as nitric oxide...
reactive nitrogen is lacking. Reactivenitrogen is a required constituent of soil used for plant growth, and it is possible that nitrogen fixing species...
and glycosaminoglycans. Eosinophil peroxidase forms reactive oxygen species and reactivenitrogen intermediates that promote oxidative stress in the target...
Nitric oxide (nitrogen oxide or nitrogen monoxide) is a colorless gas with the formula NO. It is one of the principal oxides of nitrogen. Nitric oxide...
and nitrogen dioxide) that are believed to cause peroxynitrite-related cellular damage. Its conjugate acid peroxynitrous acid is highly reactive, although...
proteins in the cell Nicotinamide riboside, a form of Vitamin B3 Reactivenitrogen (Nr) .nr, the top-level domain for Nauru New Radio, a fifth generation...
lithocholic acid (LCA) induce production of DNA-damaging reactive oxygen species or reactivenitrogen species in human or animal colon cells. Furthermore,...
"Salivary analysis in oral cancer patients: DNA and protein oxidation, reactivenitrogen species, and antioxidant profile". Cancer. 109 (1): 54–59. doi:10...
damages in proliferating cells through their generation of ROS and reactivenitrogen species (RNS). ROS and RNS are normally produced by these cells to...
Global Information
