Overview:
-Buildup in atmosphere causes acid rain.
-The main atmospheric form are sulfates (sulfuric acid, etc).
Rain Forest
Sulfur, as with Nitrogen, plays it's damaging role not in the atmosphere itself
but once converted into water soluble compounds which collect in water droplets
within clouds. These compounds are deposited by rainfall and cause damage to
plant life, animal life, and water sources.
Background:
As with all matters of atmospheric chemistry, this one is not black and white.
Atmospheric sulfur is critical to atmospheric acid-base chemistry. However,
in more recent times, human industry has thrown the sulfur cycle out of balance, leading directly to acidic rain and aerosol level increases (website). The
main atmospheric sulfur compounds are sulfates: sulfuric acid, ammonium hydrogen sulfate, and ammonium sulfate.
The following reactions occur in the troposphere:
HSO3- + H2O2 --> HSO4- + H2O
HSO3-+ O3 --> HSO4- + O2
While this reaction appears to be benefitial through the decomposition of
tropospheric ozone, the product HSO4- quickly forms H2SO4, Sulfuric acid. This, along with nitric acid (discussed in NOx) dissolve into water droplets, concentrate in clouds, and result in acidic rain.
Please visit the Land, Flora, and Water groups for information on the negative effects of acid rain.
http://www.pmel.noaa.gov/pubs/outstand/bate1229/intro.shtml
Graedel, T. E., Atmospheric Change: An Earth System Perspective.
W. H. Freeman and Company, 1993.