Download The Nitrogen Cycle

The Nitrogen Cycle
2 ~ Sampaguita
Group 6
‫ ۝‬Celz Alejandro ‫۝‬
‫ ۝‬Jade Castro ‫۝‬
‫ ۝‬Josh Quinto ‫۝‬
‫ ۝‬Cheska Regalado ‫۝‬
‫ ۝‬Geo Robeniol ‫۝‬
What is Nitrogen?
Nitrogen (N) is an essential component of
DNA, RNA, and amino acids.
All organisms require nitrogen to live and
grow.
Majority of the air we breath is N2. (78%)
Most of the nitrogen in the atmosphere is
unavailable for use by organisms.
What is Nitrogen?
In order for plants and animals to be able
to use nitrogen, N2 gas must first be
converted to more a chemically available
form.
Biologically available nitrogen is usually
short of supply in natural ecosystems,
limiting plant growth and biomass
accumulation.
The Nitrogen Cycle
This describes the movement of N2
between the atmosphere, biosphere, and
the lithosphere in different forms.
Nitrogen is processed and exchanged in
the various storage pools.
The processes in this cycle include
nitrogen fixation, nitrogen uptake,
nitrogen mineralization, nitrification, and
denitrification.
Nitrogen Fixation
N2 → NH4+
A process in which Nitrogen is converted
to ammonium.
Done mostly by Nitrogen fixing bacteria
in legume roots
Done by human activities such as
burning fossil fuels and use of synthetic
nitrogen fertilizers.
Nitrogen Uptake
NH4+ → Organic N
Ammonia is incorporated into protein and
other organic nitrogen compounds.
This is done, for example, by organisms
when they eat. They use nitrogen that
has been initially fixed by nitrogen fixing
bacteria.
Also known as Organismic Growth
Nitrogen Mineralization (Decay)
Organic N → NH4+
Organic Nitrogen is converted back to
ammonium when organisms die.
This is done by decomposers which
consume organic matter in the process of
decomposition.
Nitrification
NH4+ → NO3- or NO2Ammonium is transformed into nitrate or
nitrite.
Ammonium is positively charged so it
“sticks” to soil and is not leached easily
unlike nitrate (NO3-) and nitrite (NO2-)
Denitrification
NO3- or NO2- →N2 + N2O
Oxidized forms of nitrogen are turned to
into dinitrogen and sometimes, nitrous
oxide gas.
Done by denitrifying bacteria.
Denitrification returns Nitrogen to the
atmospehere.
Remember.....
In the Nitrogen Cycle, nitrogen undergoes
chemical reactions, changes form, and moves
through different reservoirs on earth.
Nitrogen is needed by organisms as it is the
essential component of Amino Acids.
The Five processes – Fixaton, Uptake,
Mineralizatoin, Nitrification, and Denitrificaton are mostly driven by microorganisms.
Humans influence this biogeochemical cycle
with the ise of nitrogen-based fertilizers.
Quiz
1.) What is the most common way that
nitrogen fixation occurs?
a. Lightning
b. Nitrogen Fixing Bacteria
c. Fossil Fuels
d. Forest Fires
Quiz
1.) What is the most common way that
nitrogen fixation occurs?
a. Lightning
b. Nitrogen Fixing Bacteria
c. Fossil Fuels
d. Forest Fires
Quiz
2.) Atmospheric Nitrogen is easily taken up
and used by organisms.
a. True
b. False
c. I don't know
d. Tralse?
Quiz
2.) Atmospheric Nitrogen is easily taken up
and used by organisms.
a. True
b. False
c. I don't know
d. Tralse?
Quiz
3.) Organic nitrogen is converted back to
inorganic nitrogen like ammonium in the
process of ____
a. Nitrogen Fixation
b. Nitrification
c. Nitrogen Mineralization (Decay)
d. None of the above
Quiz
3.) Organic nitrogen is converted back to
inorganic nitrogen like ammonium in the
process of ____
a. Nitrogen Fixation
b. Nitrification
c. Nitrogen Mineralization (Decay)
d. None of the above
Quiz
4.) Ammonium (NH4) stays in soil, while
nitrate (NO3) is easily leached out. Why
do they behave so differently?
a. NO3 is easily carried by bacteria
b. NH4 has a positive charge
c. NH4 is unavailable to organisms
d. None of the above
Quiz
4.) Ammonium (NH4) stays in soil, while
nitrate (NO3) is easily leached out. Why
do they behave so differently?
a. NO3 is easily carried by bacteria
b. NH4 has a positive charge
c. NH4 is unavailable to organisms
d. None of the above
Quiz
5.) Which process releases dinitrogen gas
(N2) back into the atmosphere?
a. Denitrification
b. Nitrogen Fixaton
c. Nitrogen Mineralization (Decay)
d. Nitrification
Quiz
5.) Which process releases dinitrogen gas
(N2) back into the atmosphere?
a. Denitrification
b. Nitrogen Fixaton
c. Nitrogen Mineralization (Decay)
d. Nitrification
Quiz
6.) Once bacteria have fixed nitrogen, it
can be taken up by plants and animals,
where it is used in the production of ____
a. Nitrogen oxides
b. Carbohydrates
c. Proteins
d. Energy
Quiz
6.) Once bacteria have fixed nitrogen, it
can be taken up by plants and animals,
where it is used in the production of ____
a. Nitrogen oxides
b. Carbohydrates
c. Proteins
d. Energy
Quiz
7.) Synthetic fertilizers add ____ to the soil.
a. Fixed nitrogen (Ammonium)
b. Organic Nitrogen
c. Nitrogen Oxides
d. Nitrate
Quiz
7.) Synthetic fertilizers add ____ to the soil.
a. Fixed nitrogen (Ammonium)
b. Organic Nitrogen
c. Nitrogen Oxides
d. Nitrate
Quiz
8.) Legumes host nitrogen fixing bacteria
and, thus are good crops to replenish the
soil.
a. True
b. False
c. I don't know
d. Tralse?
Quiz
8.) Legumes host nitrogen fixing bacteria
and, thus are good crops to replenish the
soil.
a. True
b. False
c. I don't know
d. Tralse?
Thanks, Bye!