THE SULFUR CYCLE

sulfur- A chemical element that occurs naturally as a pure element

- It is a abundant and  a bright yellow crystalline solid when at room temperature

- An essential element of life that is vital and widely used in the biochemical cycle

- Most of the Earth’s sulfur is tied up on rocks and salts buried in the depths of the ocean.

- Important in the functioning of proteins and enzymes in plants and animals and is present in proteins, amino acids, vitamins, and enzymes, necessary for plants and animals

- The 10th most abundant element in the environment

- Used for things such as fertilizers, matches and insecticides.

THE SULFUR CYCLE

The essential steps of the sulfur cycle are:

1. Mineralization of organic sulfur to the inorganic form, hydrogen sulfide(H2S).

2. Oxidation of sulfide and elemental sulfur (S) and related compounds to sulfate (SO4

2–).

3. Reduction of sulfate to sulfide.4. Microbial immobilization of the sulfur compounds and subsequent incorporation into the organic form of sulfur.

EFFECTS OF SULFUR ON

NATURE

1. Natural weathering of rocks, landforms, etc.

2. Volcanoes release large amounts of sulfur dioxide gas (SO2) into the atmosphere

3. SO2 gas can react chemically with oxygen, dust particles and water to form volcanic smog

HUMAN IMPACT ON SULFUR CYCLE

1. Burning of fossil fuels from factories and automobiles releases SO2 into the atmosphere

2. SO2 combines with water in clouds which creates acid rain (H2 SO4)

3. Acid rain slowly erodes structures, both natural and man made

HOW CAN WE STOP ACID RAIN?

Burning fossil fuels is the number one contributor to hydrogen sulfide pollution

Cutting back on driving or riding a bicycle can be a big help in stopping acid rain

Not using sulfate rich fertilizers will also help prevent acid rain

Henrich, 2012

Sievert, S. M., Kiene, R. P., et. al. 2007.

The Sulfur Cycle

www4.ncsu.edu/~franzen/public_html/

Poland/Poznan08a/Sulfur_Cycle.pdf

REFERENCES