Biogeochemical Cycles

1. Biogeochemical Cycles

2. Biogeochemical Cycles describe the flow of elements from the environment through living things and back to the environment.

3. Biogeochemical Cycles Reservoirs places (called reservoirs) where the elements are accumulated or held Assimilation Transfer of elements from the abiotic into the biotic Release Transfer of elements from the biotic back into the abiotic

4. Hydrological Cycle(water cycle) Reservoirs Open water - oceans, lakes, rivers…… Water vapor -clouds, fog Groundwater Glaciers, snow and ice

5. Hydrological Cycle(water cycle) Assimilation plants • absorb water from the ground animals • drink water • eat other organisms which are composed mostly of water

6. Hydrological Cycle(water cycle) Release plants • Transpiration from leaves of plants animals • Breathing releases water vapor • Expel liquid wastes • Evaporation off the surface of the body

7. Hydrological Cycle

8. Carbon Cycle(carbon is required for building organic compounds) Reservoir The atmosphere (as CO2) Fossil fuels (oil, coal,…) Organic materials (tissues of plants and animals).

9. Carbon Cycle(carbon is required for building organic compounds) Assimilation plants use CO2 in photosynthesis animals consume plants or other animals made up of carbon compounds

10. Carbon Cycle(carbon is required for building organic compounds) Release plants release CO2 during breathing and decomposition animals release CO2 during breathing and decomposition CO2 is released during combustion of fossil fuels and other materials

11. Carbon Cycle

12. Nitrogen Cycle(Nitrogen is required for the manufacture of amino acids and nucleic acids) Reservoirs In the atmosphere (as N2) In the soil as NH4+ or ammonium NH3 or ammonia N02- or nitrite N03- or nitrate

13. Nitrogen Cycle(Nitrogen is required for the manufacture of amino acids and nucleic acids) Assimilation plants can absorb either NH4+ or N03- animals obtain nitrogen by eating plants and other animals

14. Nitrogen Cycle(Nitrogen is required for the manufacture of amino acids and nucleic acids) The stages in the assimilation of nitrogen: Nitrogen Fixation: Some bacteria turn N2 toNH4+ Lightning and radiation turn N2 to N03- Nitrification: Some bacteria turn NH4+ to N02- thentoN03-

15. Nitrogen Cycle(Nitrogen is required for the manufacture of amino acids and nucleic acids) Release Denitrifying bacteria change N03- backto N2 Animals excrete NH4+or NH3 in their urine

16. Nitrogen Cycle

17. Phosphorus Cycle(Phosphorus is required for the manufactureof ATP and all nucleic acids) Reservoir sediment and rocks contain phosphorus. When they erode, they transfer phosphorus into the water and soil

18. Phosphorus Cycle(Phosphorus is required for the manufactureof ATP and all nucleic acids) Assimilation plants absorb inorganic phosphatefrom the soil animals obtain organic phosphorus when they eat plants or other animals

19. Phosphorus Cycle(Phosphorus is required for the manufactureof ATP and all nucleic acids) Release plants release phosphorus when they decompose animals release phosphorus when they decompose animals excrete phosphorus in their waste products

20. Phosphorus Cycle