1. Nitrogen Cycle

2. Nitrogen Most abundant element in the atmosphere 78% of the air we breathe is N ₂

3. Nitrogen Reservoirs Atmosphere Plants Animals Soil

4. Nitrogen All living things contain nitrogen! Building block of amino acids, proteins and DNA

5. Nitrogen Organisms cannot use Atmospheric nitrogen (N ₂) N ₂ has to become “fixed” so organisms can use it

6. Nitrogen Fixation 1.Biological: Bacteria and fungi Bacteria forms a mutualistic relationships with plants Bacteria forms a mutualistic relationships with plants

7. Nitrogen Fixation 2. Atmospheric: Lightning Lightning has enough energy to break the bonds in N ₂ creating NO ₂ Lightning has enough energy to break the bonds in N ₂ creating NO ₂

8. Nitrogen Fixation 3. Industrial: Fertilizer  Ammonia is formed under high pressure

9. Haber - Bosch German scientists who developed fertilizer German scientists who developed fertilizer Same process created chemical warfare Same process created chemical warfare

10. Chemical Warfare WWI 15,000 died in 1 st battle WWI 15,000 died in 1 st battle Mustard gas Mustard gas

11. Usable: Ammonia: NH 3 Ammonium: NH ₄ Nitrates: NO ₃ Unusable: Atmospheric: N ₂ Nitrites: NO ₂ Unusable: Atmospheric: N ₂ Nitrites: NO ₂ LIFE ON EARTH DEPENDS ON BACTERIA AND FUNGI THAT TRANSFORM NITROGEN INTO USEABLE FORMS LIFE ON EARTH DEPENDS ON BACTERIA AND FUNGI THAT TRANSFORM NITROGEN INTO USEABLE FORMS Plants cannot use atmospheric nitrogen N ₂ Plants cannot use atmospheric nitrogen N ₂ Animals must get their nitrogen from eating plants and other animals Animals must get their nitrogen from eating plants and other animals

12. Ammonification NH 3 NH ₄ The process of converting atmospheric nitrogen (N ₂) to ammonia NH 3 and ammonium NH ₄ NH 3 NH ₄ N ₂  NH 3 OR NH ₄

13. Nitrification NH 3 NH₄ NO₂ NO ₃ The process of converting ammonia NH 3 or ammonium NH₄ to nitrites NO₂ or nitrates NO ₃ NH 3 OR NH₄  NO ₃ OR NO₂ NH 3 OR NH₄  NO ₃ OR NO₂

14. Denitrification NO ₃ NO₂ The process of converting nitrates NO ₃ or nitrites NO₂ into atmospheric nitrogen N ₂ NO ₃ OR NO₂  N₂ NO ₃ OR NO₂  N₂