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The important sulfur cycle is a biogeochemical cycle in which the sulfur moves between rocks, waterways and living systems. It is important in geology as it affects many minerals and in life because sulfur is an essential element (), being a constituent of many proteins and cofactors, and sulfur compounds can be used as oxidants or reductants in microbial respiration. [1]
The global sulfur cycle involves the transformations of sulfur species through different oxidation states, which play an important role in both geological and biological processes. Earth's main sulfur sink is the oceans SO 4 2−, where it is the major oxidizing agent. [47]
The slow cycle operates through rocks, including volcanic and tectonic activity. There are fast and slow biogeochemical cycles. Fast cycle operate in the biosphere and slow cycles operate in rocks. Fast or biological cycles can complete within years, moving substances from atmosphere to biosphere, then back to the atmosphere.
The field focuses on chemical cycles which are either driven by or influence biological activity. Particular emphasis is placed on the study of carbon, nitrogen, oxygen, sulfur, iron, and phosphorus cycles. [1] Biogeochemistry is a systems science closely related to systems ecology.
Biogeochemical cycles play an important role in sustaining the biosphere. Notable active chemical cycles on Earth include: Carbon cycle – consisting of an atmospheric carbon cycle (and carbon dioxide cycle), terrestrial biological carbon cycle, oceanic carbon cycle and geological carbon cycle
Sulfur is essential and ubiquitous, partly because it is part of the amino acids cysteine and methionine. Many metals that appear as enzyme cofactors are bound by cysteine, and methionine is essential for protein synthesis. Toxic in some forms. tantalum: 73: 1c: Has no known biological role, but is biocompatible, used in medical implants, e.g ...
Sulfur is present in the environment in solids, gases, and aqueous species. Sulfur-containing solids on Earth include the common minerals pyrite (FeS 2), galena (PbS), and gypsum (CaSO 4 •2H 2 O). Sulfur is also an important component of biological material, including in the essential amino acids cysteine and methionine, the B vitamins ...
The microbial oxidation of sulfur is an important link in the biogeochemical cycling of sulfur in environments hosting both abundant reduced sulfur species and low concentrations of oxygen, such as marine sediments, oxygen minimum zones (OMZs) and hydrothermal systems. [3]