Download The Nitrogen Cycle - Dillon Environmental Science

The Nitrogen
Cycle
Noah Carter
Rio Chamberlain
Morgan Howell
Pathway of
Movement:
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The Nitrogen Cycle starts with
Atmospheric Nitrogen (N2), This form of
Nitrogen is the most abundant gas in the
Atmosphere.
It makes up 78% of the Atmosphere
Then N2 is converted to ammonia(NH3)
by Rhizobium, bacteria living in small
nodules on the roots of plants, such as
Alfalfa and Soybeans through the process
of Nitrogen Fixation.
After N2 is converted to NH3 , it is
converted to Nitrite ions(NO2 -),Toxic to the
plants, and then to Nitrate ions(NO3 -)
which then can be used as a nutrient,
which is referred to as Nitrification.
Assimilation, in which plants can absorb
inorganic Ammonia, Ammonium, and
Nitrate ions, they use these to make
Nitrogen Containing organic molecules
such as DNA, amino acids, and proteins.
Then during the process of
Ammonification, decomposer bacteria
convert nitrogen containing organic
compounds into simpler nitrogen containing
inorganic compounds such as NH3 and NH4
+.
The last step of the Nitrogen cycle is
Denitrification, which is the process by
which NH3 and NH4+ are converted back to
Nitrite and Nitrate, and the into Nitrogen
Gas.
Then the cycle starts over again!!
IMPACT OF HUMAN
INTERVENTION ON THE
NITROGEN CYCLE:
3
Burning Fossil Fuels increases Nitrogen Levels, the
nitrogen released combines with sulfur to form acid rain
Human impact has nearly doubled the amount of global
Industrial Nitrogen Fixation
Have impacted the availability of Nitrogen in ecosystems
• The unnatural addition of Nitrogen by humans has
caused unequal amounts of nutrients in trees, changes in
forest areas, and decrease of Biodiversity
Fertilizer runoff from farms and fields can leak into
aquifers of our drinking water
Our affects we have on the Nitrogen Cycle leads to the
affecting other cycles as well
• Ex.) An increase in Nitrogen due to Industrial Nitrogen
Fixation on a worldwide scale causes a change in carbon
storage.
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Inorganic and Organic Reservoirs
of Nitrogen:
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Organic Reservoirs: Contains Carbon and
derives from the environment, essential.
•
Amino Acids
Proteins
Nucleic Acids such as DNA and RNA
Atmosphere(N2)
Groundwater(NO2-) and (NO3-)
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Inorganic Reservoirs: Man-made and
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doesn’t contain Carbon
Ammonia(NH3)
Ammonium(NH4+)
Fertilizers
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During Nitrogen Fixation:
Atmospheric Nitrogen to
Ammonia
N2 to NH3
 During Nitrification:
Ammonia to Nitrites
NH3 - to NO2  During Nitrification:
Nitrites to Nitrates
NO2 - to NO3  During Ammonification:
Waste into Ammonia(NH4-)
Ammonium(NH4+)
During Denitrification:
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From Ammonia to Atmospheric
Nitrogen
NH3 - to N2
Chemical
Reactions
Involved:
6
Works Cited
 "The
Nitrogen Cycle: Processes, Players,
and Human Impact." Nature.com.
Nature Publishing Group, n.d. Web. 27
Sept. 2013.
<http://www.nature.com/scitable/kn
owledge/library/the-nitrogen-cycleprocesses-players-and-human15644632>.