Nitrogen

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

• Inorganic
• 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
  acidatmospheric 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

• Inorganic
• 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!