Sulfur Cycle Flashcards
Why are sulfur transformations complex?
- due to variety of oxidation states
How do sulfur cycle reactions occur?
Chemically and biologically
Where are sulfate mineral reservoirs?
Rocks and oceans, sediments
What is the rotten egg smell when stepping in waterlogged soil? What are the bubbles?
Sulfur oxide (H2S)
methane
Where does bacterial oxidation of sulfide occur?
interfaces of oxic/anoxic areas
Where are hyperthermophiles found?
- in thermal vents (lots of sulfur)
Define phototrophic
light must be present to carry out reactions
Define thiobacillus, where are they found?
- elemental sulfur oxidizer and sulfur transformer
- found in acidic environments
Are chemolithotrophs organic or inorganic?
- inorganic
Where does H2S get trapped and oxidized in the cycle?
in anoxic area, oxidized in anoxic conditions and feeds other parts of the cycle
What is S0?
- readily oxidized by sulfur-oxidizing bacteria to form sulfate and H2
- elemental sulfur
What is an example of a sulfur oxidizer?
Thiobacillus
What happens to conditions when S0 is oxidized?
acidification (pH drop)
How does S0 form H2S? What is this carried out by?
- via anaerobic reduction
= hyperthermophilic archaea
What causes a drop in pH during S0 oxidation?
accumulation of H+
