Environmental science presentation on the nitrogen cycle.

1. Names:
Subject: Environmental Science
cape unit 1

2. The nitrogen cycle is a series of processes that convert nitrogen gas to
organic substances and back to nitrogen in nature. It is a repeated cycle
that is maintained by the decomposers and nitrogen bacteria.
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3. Ammonification(Decay)
• This is certain soil bacteria and fungi
e.g. ammonifying bacteria – that break
down proteins in dead organisms and
animal wastes, releasing ammonium
ions.
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4. Nitrification
• This is a two-step process that is carried out by the
nitrifying bacteria. Ammonia or ammonium ions
are oxidized first to nitrites and then to nitrates.
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5. Denitrification
• Is the bacterial or other microbial process
in which nitrates and nitrites are reduced or
removed from soil, water, or air by their
conversion into nitrogenous gases
.
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6. There are three types of Nitrogen fixation:
Atmospheric fixation - this occurs spontaneously due to
lightning. Only a small amount is fixed this way.
Industrial fixation - the Haber process which involves the
combination N2 and H is used to make nitrogen
fertilizers.
Biological fixation – Is the transformation the unusable
form of nitrogen into other compounds that are more
readily usable.
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7. 7
• Helps plants to synthesize chlorophyll from the nitrogen
compounds.
• Helps in converting inert nitrogen gas into a usable form for
the plants through the biochemical process.
• In the process of ammonification, the bacteria help in
decomposing the animal and plant matter, which indirectly
helps to clean up the environment.
• Nitrates and nitrites are released into the soil, which helps in
enriching the soil with the necessary nutrients required for
cultivation.
• Nitrogen is an integral component of the cell and it forms
many crucial compounds and important biomolecules.

8. Videoexplanation of the Nitrogen cycle 8