NAME: KHADIJA ABID
CLASS: O’LEVEL C-III
.
NITROGEN CYCLE: THE
CIRCULATION OF NITROGEN FROM
ATMOSPHERE TO THE SOIL AND BACK
INTO THE ATMOSPHERE.
.
1:NITROGEN FIXATION
THE PROCESS IN WHICH ATMOSPHERIC
NITROGEN IS CONVERTED INTO
AMMONIA.
2:NITROGEN ASSIMILATION
THE PROCESS OF ABSORBING
NITRATES AND AMMONIA.
3:AMMONIFICATION
The process of converting nitrogen into Ammonia
when animals die.
 Also known as Mineralization.
 The process was carried out by some saprophytes
like Fungi and Bacteria.
 Ammonia is also produced from Volcanic
eruptions and excretory products of Animals.

4: NITRIFICATION
Ammonia
Nitrites(Nitrococcus)
Nitrates(Nitrobacter).
Nitrifying Bacteria : Bacterias that are involved in
nitrification.

5:DENITRIFCATION
THE PROCESS IN WHICH NITRATES ARE CONVERTED
INTO NITROGEN THROUGH NITRIC OXIDE.
IMPACT OF HUMANS ON
NITROGEN CYCLE

Amount of Nitrogen in air increases due to
burning of fossil fuels, nitrogen-based fertilize
and industrial waste nitrogen.
Acid rain formation
 Desertification
 Acidification

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