Post on 17-May-2015
Sulfur Cycle
Sedimentary and Gaseous
• Sedimentary cycle– Weathering of rock and leaching of its minerals,
transport, deposition and burial.• Gaseous Cycle– A biogeochemical cycle with the main reservoir or
pool of nutrients in the atmosphere and ocean
Sulfur enters the biosphere through
• Natural Activity
Weathering of rocks and decomposition
Carried through terrestrial environments in salt
solution.
PlantsConsumers
Sulfur enters the atmosphere through
• Natural Activity
Volcanic eruptions, gases released by decomposition
• Human Activity
Burning of fossil fuels, acidic drainage from mines
Enters atmosphere as H2S and reacts with oxygen to
form SO2
SO2 is soluble in H2O Acid rain (H2SO4)
plantsconsumers
Death of consumers Sulfur to the atmosphere
soilPonds, lakes, seas and oceans
Different kinds of bacteria process this sulfur
Non-photosynthetic photosynthetic
Colorless sulfur bacteria
Purple bacteria
Green bacteria
Sulfur
Iron
Ferrous sulfide (FeS2)
Sulfur from the oceans
Released in the atmosphere as Dimethyl sulfide ((CH3)2S )
Go back to the atmosphere by bacteria fixation, or sea
sprays