Nitrogen Cycle

1
Nitrogen gas in the atmosphere N2
air
soil
Nitrogen in dead animals and plants
Nitrogen in ammonium compounds in soil NH4
Nitrogen in nitrates in soil water NO3-
Nitrogen in nitrites in soil water NO2-
2
Nitrogen gas in the atmosphere
Legumes
air
soil
Nitrogen in dead animals and plants
Nitrogen in ammonium compounds in soil
Nitrogen in nitrates in soil water
Nitrogen in nitrites in soil water
3
Some nitrates are turned back into nitrogen gas
Nitrogen gas in the atmosphere N2
Using nitrogen from the air
Lightning converts Nitrogen to nitrates
Denitrifying bacteria
air
soil
Nitrogen in dead animals and plants
Fertiliser factories
Nitrogen in ammonium compounds in soil NH4-
Nitrogen in nitrates in soil water NO3-
Nitrogen in nitrites in soil water NO2-
nitrates leached into river water
Nitrifying bacteria
4
Some nitrates are turned back into nitrogen gas
Nitrogen gas in the atmosphere N2
Using nitrogen from the air
Lightning converts Nitrogen in nitrates
Denitrifying bacteria
air
soil
Nitrogen in dead animals and plants
Fertiliser factories
Nitrogen in ammonium compounds in soil NH4-
Nitrogen in nitrates in soil water NO3-
Nitrogen in nitrites in soil water NO2-
nitrates leached into river water
Nitrifying bacteria
5
(No Transcript)
6
Effect of adding nitrogen too late?
Effect of adding nitrogen too soon?
7
Some nitrates are turned back into nitrogen gas
Nitrogen gas in the atmosphere N2
Using nitrogen from the air
Lightning converts Nitrogen in nitrates
Denitrifying bacteria
air
soil
Nitrogen in dead animals and plants
Fertiliser factories
Nitrogen in ammonium compounds in soil NH4-
Nitrogen in nitrates in soil water NO3-
Nitrogen in nitrites in soil water NO2-
nitrates leached into river water
Nitrifying bacteria
8
nitrates leached into river water
Algae and surface plants grow larger
Eutrophication
Large plants grow
Deep water plants receive less light and die
Fish die due to shortage of oxygen
Microbes feed on dead plants and use up more
oxygen
9
nitrates leached into river water
Eutrophication
Large plants grow
10
(No Transcript)
11




air
soil






B493-15.4

12
Eutrophication

Large plants grow



B493-15.4