what are the processes of the nitrogene cycle?

Question:

Answers:
ASSUMING YOU MEANT NITRIGEN CYCLE
Nitrogen Fixation
Main article: Nitrogen fixation
[edit]
Conversion of N2
There are four ways to convert N2 (atmospheric nitrogen gas) into more chemically reactive forms (Smil, 2000):

The conversion of dinitrogen(N2)from the atomsphere into a form available to plants and hence to animals and humans. This is an important step in the terrestrial nitrogen cycle

Biological fixation : some symbiotic bacteria (most often associated with leguminous plants) and some free-living bacteria are able to fix nitrogen and assimilate it as organic nitrogen. An example of mutualistic nitrogen fixing bacteria are the Rhizobium bacteria, which live in plant root nodes. These species are diazotrophs.
Industrial N-fixation ; in the Haber-Bosch process, N2 is converted together with hydrogen gas (H2) into ammonia (NH3) fertilizer.
Combustion of fossil fuels : automobile engines and thermal power plants, which release NOx.
Other processes : Additionally, the formation of NO from N2 and O2 due to photons and lightning, are important for atmospheric chemistry, but not for terrestrial or aquatic nitrogen turnover.
As a result of extensive cultivation of legumes (particularly soy, alfalfa, and clover), use of the Haber-Bosch process in the creation of chemical fertilizers and pollution emitted by vehicles and industrial plants, human beings have more than doubled the annual transfer of nitrogen into a biologically available form (Vitousek et al, 1997). This has occurred to the detriment of aquatic and wetland habitats through eutrophication.

[edit]
Assimilation
In plants which have a mutualisic relationship with Rhizobium, some nitrogen is assimilated in the form of ammonium ions from the nodules. All plants however, can absorb nitrate from the soil via their root hairs. These are then reduced to nitrate ions and then ammonium ions for incorporation into amino acids, and hence protein, which forms part of the plants or animals that they eat (Smil, 2000).

[edit]
Ammonification
Nitrates are the form of nitrogen most commonly assimilated by plant species, which, in turn are consumed by heterotrophs for use in compounds such as amino and nucleic acids. The remains of heterotrophs will then be decomposed into nutrient-rich organic material. Bacteria or in some cases, fungi, will convert the nitrates within the remains back into ammonia.

[edit]
Nitrification
Main article: Nitrification
The conversion of ammonia to nitrates is performed primarily by soil-living bacteria. The primary stage of nitrification, the oxidation of ammonia (NH3) is performed by bacteria such as the Nitrosomonas species, which converts ammonia to nitrites (NO2-). Other bacterial species, such as the Nitrobacter, are responsible for the oxidation of the nitrites into nitrates (NO3-) (Smil, 2000)

[edit]
Anaerobic Ammonium Oxidation
Main article: Anammox
In this biological process, nitrite and ammonium are converted directly into dinitrogen gas. This process makes up a major proportion of dinitrogen conversion in the oceans.

[edit]
Denitrification
Main article: Denitrification
Denitrification is the reduction of nitrates back into the largely inert nitrogen gas (N2), completing the nitrogen cycle. This process is performed by bacterial species such as the Pseudomonas (Smil, 2000) .

Source(s):
http://en.wikipedia.org/wiki/Nitrogen_cycle

2 weeks ago - Report Abuse

More Questions and Answers

The consumer health information on youqa.com is for informational purposes only and is not a substitute for medical advice or treatment for any medical conditions.
The answer content post by the user, if contains the copyright content please contact us, we will immediately remove it.

what are the processes of the nitrogene cycle?

Health Resources