Transcript The Nitrogen Cycle

Nitrogen Cycle
Geochemical cycles are beautiful and
wonderfully complex. One of the most
dynamic of these is the Nitrogen cycle.
Describe the cycle and how Nitrogen is
stored in the ecosystem. Be sure to
include in your description how Nitrogen
changes form to become available for
plant usage and its importance in
biological systems.
Geochemical cycles are beautiful and
wonderfully complex. One of the most
dynamic of these is the Nitrogen cycle.
Describe the cycle and how Nitrogen is
stored in the ecosystem. Be sure to
include in your description how Nitrogen
changes form to become available for
plant usage and its importance in
biological systems.
Some Uses
• Production of organic molecules by plants
and animals. Ex: amino acids, proteins,
nucleic acids
• Plant nutrient- major one for vegetative
growth.
Amino acids
Storage Sites
• Major area is the
atmosphere
• Organic matter in the
soil and in the oceans
The Forms of Nitrogen in Storage
The Cycle
• Abundance is “tricky” because it is the
most limiting nutrient for plant growth
• Plants take up in the form (s)
– NH4+ ammonium (to much is toxic)
– NO3- nitrate (soil solutions that are prone to
leach)
The Cycle
Transformations to Usable Forms
Mineralization
Organic matter --- decomposers--(bacteria, actinomycetes, and fungi)
---ammonia(NH4+) and (NH4+) ammonium
salts
Transformations cont.
Micelle fixation
• NH4+ absorbed onto clay particles released from
colloids by cat-ion exchange
Nitrification
• Nitrosomonas autotropic bacteria converts
ammonia to nitrite NH3+ --- NO2• Nitrobactor autotropic bacteria convert Nitrite to
Nitrate
NO2- --- NO3-
The Cycle
• Nitrogen returns to environment
– Leaching through soil profile and the into
bodies of water
– Nitrogen in Soil and Water goes through
denitrification • Anaerobic (without oxygen) process
• NO3N2(g) reduction
N2O(g)
The Nitrogen Cycle
Bibliography
• http://www.science.duq.edu/esm/Course_
Material/ESM552/Notes/Chapter2/GIFS/fig
2_8.GIF
• www.lloydminsterheavyoil.com/
buildheavy.htm
• bouman.chem.georgetown.edu/.../
nitrogen.4.jpeg
• www.edunet.tn/.../la%20liaison/
la%20liaison.htm
• www.cmbi.kun.nl/.../infopages/ aminoacids.shtml