Transcript Sulfur - SOIL 5813

The Sulfur Cycle
*Additional
S
Information
Atmospheric SO2
(CH3)2S
COS
SO42- in
ocean
H2S
(CH3)2S
H2S
COS
Fossil Fuel
Combustion
Volcanoes
FeS2
volatilization
SO32-, SO42-
H2S
smelting/refining
electricity generation
Photosynthetic
anaerobic bacteria
swamps,lakes
estuaries
CO2
light
H2S
S2-
Biomass
burning
Desulfuromanas
mineralization
Soil solution SO42-
CaSO4
River sediment
Inorganic S
Atmospheric SO2
dry deposition
Irrigation
water
Fertilizers
O3
SO4 in
rainfall
pH>7; less SO42absorbed by plants
2H2SO4
mineralization, redox reactions
Soil solution
SO42-
decomp
microbial
2S + 3O2 + 2H2O
Organic S
Inorganic S
H 2S
+O2
Authors: Xin Li, Dale Keahey, Jeremy Dennis,
Michael Blazier, and Chris Stiegler
S2-
Leaching
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General
Concentrations
Mobility in
plant
Effect of pH on
availability
Mobility in soil
Deficiency
symptoms
Interaction with
other nutrients
Enzymes needing S
Fertilizer
sources
Role of nutrient in
plant and microbial
growth
Industrial uses
References
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General Facts
• Sulfur is a pale yellow, non-metallic solid.
• Name was derived from the Latin word for brimstone (“burning stone”),
since it burns readily in air.
• Elemental sulfur has been used since ancient times in religious
ceremonies, to fumigate buildings, and for bleaching cloth. Also used
agriculturally to lower the pH of soil.
• During the Middle Ages, sulfur was one of the principal reagents used
by alchemists in their search for the philosopher’s stone, believed to
contain the secret of life. Modern chemistry has put sulfur to many
other uses.
• Large sedimentary deposits around the Gulf of Mexico and in Italy are
extensively mined, as are volcanic deposits in Japan, Chile, and
Indonesia.
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Form taken up by plants:
SO42-, SO32- (low levels
adsorbed through leaves)
Mobility in plant:
Yes
Mobility in soil:
Yes
Deficiency symptoms:
Leaves chlorotic (upper
leaves), reduced plant
growth, weak stems
Enzymes needing
sulfur and biological
compounds
containing sulfur:
Coenzyme A, ferrodoxin,
biotin, thiamine, glutathione,
pyrophoshates, urease, and
sulfotransferases
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Role of nutrient in plant and
microbial growth
• Sulfur atoms play important roles in the biochemistry of plants, animals,
and microorganisms.
• Synthesis of the S-containing amino acids cystein, cystine, and methionine;
synthesis of other metabolites, including CoA, biotin, thiamine, and
glutathione; main function in proteins is the formation of disulfide bonds
between polypeptide chains; component of other S-containing substances,
including S-adenosylmethionine, formylmethionine, lipoic acid, and
sulfolipid; about 2% of the organic reduced sulfur in the plant is present in
the water soluble thiol (-SH) fraction; vital part of ferredoxin; responsible for
the characteristic taste and smell of plants in the mustard and onion
families; enhances oil formation in flax and soybeans; sulfate can be
utilized without reduction and incorporated into essential organic structures;
reduced sulfur can be re-oxidized in plants.
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Concentration in plants:
0.1 and 0.5% of the dry wt.
of plants
Concentration in earth’s
crust:
0.05%
Effect of pH on availability:
pH<6.5, AEC increases
with decreasing pH
Interaction with other
nutrients:
associated with salts and
exchangeable cations, can
be replaced by phosphorus
on exchange sites; also
interconnects with the
calcium and nitrogen
cycles in important ways
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Fertilizer Sources
• Organic matter, ammonium bisulfite, ammonium
nitrate-sulfate, ammonium phosphate-sulfate,
ammonium polysulfide, ammonium sulfate, ammonium
thiosulfate, ferrous sulfate, gypsum, magnesium
sulfate, potassium sulfate, pyrites, potassium
thiosulfate, potassium polysulfide, sulfuric acid
(100%), sulfur, sulfur dioxide, single superphosphate,
triple superphosphate, urea-sulfur, urea-sulfuric acid,
and zinc sulfate
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Industrial Uses/Fun Facts
• Sulfur is used to manufacture wood
pulp, rubber, insecticides, fertilizers, and
many medicines.
• Hair, wool, albumen, mustard, garlic,
horseradish, and cabbage all contain
appreciable amounts of sulfur, as do
many proteins.
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References
• Hartmann, H.T., Kofranek, A.M., Rubatzky, V.E., Flocker, W.J.
(1988). Plant Science. 2nd ed. Prentice Hall. Englewood
Cliffs, NJ.
• Marschner, H. (1995). Mineral Nutrition of Higher Plants. 2nd
ed. Institute of Plant Nutrition Univ. Hohenheim. Academic
Press. San Diego, CA.
• Tisdale, S.L., Nelson, W.L., Beaton, J.D., and Havlin, J.L.
(1993). Soil Fertility and Fertilizers. 5th ed. Macmillan Pub.
Co. New York, NY.
• Vaughan, D., Malcolm, R.E. (1985). Soil Organic Matter and
Biological Activity. Martinus Nijhoff/Dr. W. Junk Publishers,
Dordrecht.
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