1. Nitrogen & Phosphorous
Group #3:
Neil Mehta
Misha Nelson
Tristan Jenkins
Jenna Colhouer
Brendon Esperancilla

2. Nitrogen Chemical Reactions
Inorganic and organic reservoirs for the element
Pathway of movement
Impact of human intervention on the cycle

3. Chemical Reactions
Nitrogen: (N2) most abundant element in atmosphere (78% of troposphere volume)
Combines with atmospheric oxygen to form nitrogen dioxide gas (NO2)
(N2) cannot be metabolized as a nutrient
Electrical discharges cause N2 & O2 to react
Certain bacteria (Rhizobium, etc.) can fix nitrogen for use by plants

4. Inorganic and organic reservoirs for the element
Atmospheric gas
Organic:
Plants are consumed by animals as a source of nitrogen
Detritus resulting from decomposition of formerly living organisms

5. Pathway of movement
Nitrification: ammonia converts to nitrite (NO2-) & nitrate (NO3-)
Assimilation: plant roots absorb inorganic ammonia, ammonium ions, and nitrate ions
Used for synthesis of DNA, proteins, etc.
Ammonification: bacteria decompose dead matter into constituent components, including ammonia and ammonium salts
Denitrification: bacteria convert ammonia and ammonium back into nitrite and nitrate, then becoming N2 and nitrogen oxide

6. Impact of human intervention on the cycle
When we burn any fuel, it adds large amounts of nitric oxide
Acid rain: formed by HNO3 (nitric acid=atmospheric water and nitrogen dioxide) and dissolves in rain or snow
Farm animals release methane into atmosphere

7. Phosphorous Chemical Reactions
Inorganic and organic reservoirs for the element
Pathway of movement
Impact of human intervention on the cycle

8. Chemical Reactions Very little P circulates in atmosphere
At Earth STP, P is not usually gaseous and mostly mineral
P is typically found in terrestrial rock and ocean sediment
Helps form structure of bones in animal skeletons
Often used in fertilizer
Composes ATP for nearly all cellular activities
Composes phospholipid bilayer of cell membranes
Most abundant form: orthophosphate (PO43-)

9. Inorganic and organic reservoirs for the element
Mineral formations
Ocean sediment
Organic:
Aquatic and terrestrial plants
Bones of terrestrial animal

10. Pathway of movement Starts in mineral form
Weathering deposits it in soils
Plants absorb from soil
Animals consume plants and their phosphorous
Reintegrated into soil after death of animal
Can run off into ocean
Ocean plants ocean animals
Some settles into marine sediment
Mined by humans for fertilizer

11. Impact of human intervention on the cycle
We harvest phosphorous from sediment to make fertilizer
Remove trees from tropical forests
No plants, no absorption from soil
No plant roots, no soil to begin with!
Pollute aquatic environments
Overabundance of P promotes algal bloom, which helps bacteria thrive; bacteria consume too much oxygen, and fish drown!?

12. HEY!