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sulfur cycle
community leads to succession, e.g., the change in species composition of
algae during the year, caused by the change in temperature, light, grazing, or
nutrient composition due to nutrient uptake by the growing algae.
Succession leads to stabilization of an ecosystem.
sulfate chemical symbol S04 2 - is the predominant form of sulfur in seawater,
where its concentration is 28.3 mmoll- 1 • Sulfur in the form of sulfate is after
chlorine, sodium, and magnesium the most abundant element in seawater.
It can be considered a nutrient because all living organisms need it to build
organic macromolecules, e.g., proteins.
sulfate reduction is the reduction of sulfate to sulfide. This process is executed by
the widely distributed sulfate-reducing Bacteria. These anaerobic bacteria use
sulfate as electron acceptor in the oxidization of organic matter. During the
electron transport along the electron transport system ATP is synthetized.
Such a sulfate reduction is also called dissimilative sulfate reduction. Many
organisms, including higher plants, algae, fungi, and most bacteria, use sulfate as a sulfur source for biosynthesis. This is the assimilative sulfate reduction. The obligate anaerobic sulfate-reducing bacteria play an essential role
in the mineralization of organic matter in anaerobic marine ecosystems, sediments, anaerobic fjords, and basins.
sulfides compounds with S2- as anion. In sediments beneath regions of high
productivity, where dissolved oxygen in pore waters is quickly consumed,
FeS (mackinawite or graygite) is formed from Fe (II) and H 2 S which originates from sulfate by bacterial reduction. This precipitate causes the black
layers found a few mm to several dm below the sediment surface. At deeper
levels, the black color disappears again by transformation of FeS into FeS 2
(pyrite) or other polysulfides which have a gray color. Sulfides are also precipitated from hydrothermal fluids near deep-sea hydrothermal vents in midoceanic ridges. They consist of mixtures of Fe, Ca, and Cu sulfides and contain
also Co, Mn, Pb, and other trace constituents.
sulfur bacteria are a group of bacteria that possess the capacity of chemolithotrophically (-tmetabolic diversity) oxidizing reduced sulfur compounds. -tsulfur
cycle.
sulfur cycle a biogeochemical cycle effected by various types of microorganisms. Assimilative and dissimilative sulfate reductions reduce sulfate to respectively reduced sulfur in organic matter and sulfide. Different groups of
Bacteria are specialized in the oxidation of sulfide. Colorless sulfur bacteria
oxidize sulfide with oxygen or nitrate and phototrophic sulfur bacteria can
use reduced sulfur compounds as electron donors to assimilate CO 2 in the
light (anoxygenic photosynthesis). Also some cyanobacteria are known to pos-
sulfur cycle
community leads to succession, e.g., the change in species composition of
algae during the year, caused by the change in temperature, light, grazing, or
nutrient composition due to nutrient uptake by the growing algae.
Succession leads to stabilization of an ecosystem.
sulfate chemical symbol S04 2 - is the predominant form of sulfur in seawater,
where its concentration is 28.3 mmoll- 1 • Sulfur in the form of sulfate is after
chlorine, sodium, and magnesium the most abundant element in seawater.
It can be considered a nutrient because all living organisms need it to build
organic macromolecules, e.g., proteins.
sulfate reduction is the reduction of sulfate to sulfide. This process is executed by
the widely distributed sulfate-reducing Bacteria. These anaerobic bacteria use
sulfate as electron acceptor in the oxidization of organic matter. During the
electron transport along the electron transport system ATP is synthetized.
Such a sulfate reduction is also called dissimilative sulfate reduction. Many
organisms, including higher plants, algae, fungi, and most bacteria, use sulfate as a sulfur source for biosynthesis. This is the assimilative sulfate reduction. The obligate anaerobic sulfate-reducing bacteria play an essential role
in the mineralization of organic matter in anaerobic marine ecosystems, sediments, anaerobic fjords, and basins.
sulfides compounds with S2- as anion. In sediments beneath regions of high
productivity, where dissolved oxygen in pore waters is quickly consumed,
FeS (mackinawite or graygite) is formed from Fe (II) and H 2 S which originates from sulfate by bacterial reduction. This precipitate causes the black
layers found a few mm to several dm below the sediment surface. At deeper
levels, the black color disappears again by transformation of FeS into FeS 2
(pyrite) or other polysulfides which have a gray color. Sulfides are also precipitated from hydrothermal fluids near deep-sea hydrothermal vents in midoceanic ridges. They consist of mixtures of Fe, Ca, and Cu sulfides and contain
also Co, Mn, Pb, and other trace constituents.
sulfur bacteria are a group of bacteria that possess the capacity of chemolithotrophically (-tmetabolic diversity) oxidizing reduced sulfur compounds. -tsulfur
cycle.
sulfur cycle a biogeochemical cycle effected by various types of microorganisms. Assimilative and dissimilative sulfate reductions reduce sulfate to respectively reduced sulfur in organic matter and sulfide. Different groups of
Bacteria are specialized in the oxidation of sulfide. Colorless sulfur bacteria
oxidize sulfide with oxygen or nitrate and phototrophic sulfur bacteria can
use reduced sulfur compounds as electron donors to assimilate CO 2 in the
light (anoxygenic photosynthesis). Also some cyanobacteria are known to pos-