<p>I went to do a bit of research on this, and think that you can get a satisfactory answer just from the relevant wikipedia articles. Here are some select quotes:</p>
<blockquote>
<p><a href="https://en.wikipedia.org/wiki/Nitrogen_fixation" rel="noreferrer">Nitrogen fixation</a> is a process by which nitrogen in the Earth's
atmosphere is converted into ammonia (NH3) or other molecules
available to living organisms.</p>
</blockquote>
<p>Nitrogen fixation has the chemical process:</p>
<blockquote>
<p>N<span class="math-container">$_2$</span> + 8 H<span class="math-container">$^+$</span> + 8 e<span class="math-container">$^−$</span> <span class="math-container">$\rightarrow$</span> 2 NH<span class="math-container">$_3$</span> + H<span class="math-container">$_2$</span></p>
</blockquote>
<p>and is performed by <a href="https://en.wikipedia.org/wiki/Diazotroph" rel="noreferrer">Diazotroph</a> bacteria or archaea. Some of these are symbiotic with plant roots, especially of the family <a href="https://en.wikipedia.org/wiki/Fabaceae" rel="noreferrer">Fabaceae</a>.</p>
<blockquote>
<p><a href="https://en.wikipedia.org/wiki/Nitrification" rel="noreferrer">Nitrification</a> is the biological oxidation of ammonia or ammonium to
nitrite followed by the oxidation of the nitrite to nitrate.</p>
</blockquote>
<p>An example of a nitrification chemical reaction is:</p>
<blockquote>
<p>2NH<span class="math-container">$_4^+$</span> +  3O<span class="math-container">$_2$</span> <span class="math-container">$\rightarrow$</span> 2NO<span class="math-container">$_2^−$</span> + 2 H<span class="math-container">$_2$</span>O + 4 H<span class="math-container">$^+$</span></p>
<p>2NO<span class="math-container">$_2^−$</span> + O<span class="math-container">$_2$</span> <span class="math-container">$\rightarrow$</span> 2 NO<span class="math-container">$_3^−$</span></p>
</blockquote>
<p>There are a wide variety of bacteria that peform these steps, and some only do one step or the other. There are also other pathways for reducing ammonia instead of ammonium, for example.</p>
<p>In conclusion, these are two different biologically driven steps in the <a href="https://en.wikipedia.org/wiki/Nitrogen_cycle" rel="noreferrer">nitrogen cycle</a>, driven by two different sets of microorganims. There other biologically driven processes as well, such as <a href="https://en.wikipedia.org/wiki/Nitrogen_cycle#Ammonification" rel="noreferrer">ammonification</a>, where organic nitrogen compounds in formerly living tissue (or waste) is broken down into ammonia or ammonium.</p>

CC BY-SA 3.0
2017-04-25T19:13:45.110Z
I understand that N-fixation and nitrification are two separate processes in the N cycle. I was just wondering if at any time in the literature has the name ʻnitrificationʻ been used for the process of reducing atmospheric nitrogen gas to ammonia. The thing confusing me is in this article: [link](http://ebme.marine.rutgers.edu/papers/Falkowski_Godfrey_Philos_Trans_363_May_2008.pdf) . In the first paragraph of section 6 they say that in the low oxygen Late Archaean Earth **nitrification** would be more important in imparting a del15N signature to fixed N...
chiaka
CC BY-SA 3.0
2017-04-25T19:14:00.853Z
But I understand that nitrification, being the oxidation of NH4 to NO3, requires sufficient oxygen in the environment.
chiaka
CC BY-SA 3.0
2017-04-26T15:24:25.553Z
@chiaka.dont forget to mark answers as accsepted when or if they are.
trond hansen
CC BY-SA 3.0
2017-04-25T16:44:36.230Z
2017-04-25T16:44:36.230Z
2020-06-18T08:25:19.090Z
kingledion
<p>Is 'nitrification' and 'nitrogen fixation' used interchangeably to describe biological reduction of $\ce{N2}$ gas to $\ce{NH3}$? I know $\ce{NH4} \to \ce{NO3}$ is called nitrification too.</p>

CC BY-SA 3.0
2017-04-25T11:54:55.293Z
You might get a better answer in https://chemistry.stackexchange.com/
arkaia
CC BY-SA 3.0
2017-04-25T13:15:43.673Z
do you want an answer of this for nitrogen cyckle in water or for soil,there is some differences.nitrification is the production of nitrate and nitrogen fixation is the storage of nitrate.there is also somthing called denitrification this is the release of nitrogen from nitrate.
trond hansen
<atmosphere><ocean><biogeochemistry><nitrogen>
Nitrogen cycle semantics; nitrification/nitrogen fixation
chiaka
# Nitrogen cycle semantics; nitrification/nitrogen fixation

(Asked by: username_0 on 2017-04-25)

Is 'nitrification' and 'nitrogen fixation' used interchangeably to describe biological reduction of $\ce{N2}$ gas to $\ce{NH3}$? I know $\ce{NH4} \to \ce{NO3}$ is called nitrification too.

**Tags:** atmosphere, ocean, biogeochemistry, nitrogen

> **Comments:**
> **username_1**: You might get a better answer in https://chemistry.stackexchange.com/  
> **username_2**: do you want an answer of this for nitrogen cyckle in water or for soil,there is some differences.nitrification is the production of nitrate and nitrogen fixation is the storage of nitrate.there is also somthing called denitrification this is the release of nitrogen from nitrate.  

---

## 1 answers

### Answer by username_3 on 2017-04-25. Score: 5

I went to do a bit of research on this, and think that you can get a satisfactory answer just from the relevant wikipedia articles. Here are some select quotes:

> [Nitrogen fixation](https://en.wikipedia.org/wiki/Nitrogen_fixation) is a process by which nitrogen in the Earth's
> atmosphere is converted into ammonia (NH3) or other molecules
> available to living organisms.

Nitrogen fixation has the chemical process:

> N$\_2$ + 8 H$^+$ + 8 e$^−$ $\rightarrow$ 2 NH$\_3$ + H$\_2$

and is performed by [Diazotroph](https://en.wikipedia.org/wiki/Diazotroph) bacteria or archaea. Some of these are symbiotic with plant roots, especially of the family [Fabaceae](https://en.wikipedia.org/wiki/Fabaceae).

> [Nitrification](https://en.wikipedia.org/wiki/Nitrification) is the biological oxidation of ammonia or ammonium to
> nitrite followed by the oxidation of the nitrite to nitrate.

An example of a nitrification chemical reaction is:

> 2NH$\_4^+$ + 3O$\_2$ $\rightarrow$ 2NO$\_2^−$ + 2 H$\_2$O + 4 H$^+$
>
> 2NO$\_2^−$ + O$\_2$ $\rightarrow$ 2 NO$\_3^−$

There are a wide variety of bacteria that peform these steps, and some only do one step or the other. There are also other pathways for reducing ammonia instead of ammonium, for example.

In conclusion, these are two different biologically driven steps in the [nitrogen cycle](https://en.wikipedia.org/wiki/Nitrogen_cycle), driven by two different sets of microorganims. There other biologically driven processes as well, such as [ammonification](https://en.wikipedia.org/wiki/Nitrogen_cycle#Ammonification), where organic nitrogen compounds in formerly living tissue (or waste) is broken down into ammonia or ammonium.

> **Comments:**
> **username_0**: I understand that N-fixation and nitrification are two separate processes in the N cycle. I was just wondering if at any time in the literature has the name ʻnitrificationʻ been used for the process of reducing atmospheric nitrogen gas to ammonia. The thing confusing me is in this article: [link](http://ebme.marine.rutgers.edu/papers/Falkowski_Godfrey_Philos_Trans_363_May_2008.pdf) . In the first paragraph of section 6 they say that in the low oxygen Late Archaean Earth **nitrification** would be more important in imparting a del15N signature to fixed N...  
> **username_0**: But I understand that nitrification, being the oxidation of NH4 to NO3, requires sufficient oxygen in the environment.  
> **username_2**: @username_0.dont forget to mark answers as accsepted when or if they are.  

---

