Geochemical cycles sulfur

Arthur M. A. (2000) Volcanic contributions to the carbon and sulfur geochemical cycles and global change. In Encyclopedia of Volcanoes (eds. H. Sigurdsson, B. E. Houghton, S. R. McNutt, H. Rymer, and J. Stix). Academic Press, San Diego, pp. 1046—1056. 

Andreae, M. O. (1986). The ocean as a source of atmospheric sulfur compounds. In "The Role of Air-Sea Exchange in Geochemical Cycling" (P. Buat-Menard, ed.). Reidel, Dordrecht. 

Biodegradation. Under aerobic conditions, biodegradation results in the mineralization of an organic compound to carbon dioxide and water and—if the compound contains nitrogen, sulfur, phosphorus, or chlorine—with the release of ammonium (or nitrite), sulfate, phosphate, or chloride. These inorganic products may then enter well-established geochemical cycles. Under anaerobic conditions, methane may be formed in addition to carbon dioxide, and sulfate may be reduced to sulhde. 

Sulfur enters the current geochemical cycle with the weathering of rocks and conversion to either S02 or S042 -bearing species, and subsequent uptake by plants and microorganisms and conversion into a variety of organic forms. Despite the... 

Godfrey JD (1962) The deuterium content of hydrous minerals from the East Central Sierra Nevada and Yosemite National Park. Geochim Cosmochim Acta 26 1215-1245 Goericke R, Fry B (1994) Variations of marine plankton 6 C with latitude, temperature and dissolved CO2 in the world ocean. Global Geochem Cycles 8 85-90 Goldhaber MB, Kaplan IR (1974) The sedimentary sulfur cycle. In Goldberg EB (ed) The sea, vol. 4. WUey, New York... 

Kump LR (1989) Alternative modeling approaches to the geochemical cycles of carbon, sulfur and strontium isotopes. Am J, Sd 289 390-410 Kump LR (2005) Ironing out biosphere oxidation. Science 307 1058-1059 Kump LR, Arthur MA (1999) Interpreting carbon-isotope excursions carbonates and organic matter, Chem Geol, 161 181-198... 

It is not surprising that the geochemical cycle of sulfur during the I0W-O2 Archean differed from that of the present day. As shown in Figure 5, the mass-dependent fractionation of the sulfur isotopes in sedimentary sulfides was smaller prior to 2.7 Ga than in more recent times. Several explanations have been advanced for this observation. The absence of microbial sulfate reduction is one. However, the presence of... 

This global cycling of sulfur is closely linked to other geochemical cycles as well. In particular, it is tied to the abundance of atmospheric oxygen. 

Kump L. R. (1989) Alternative modeling approaches to the geochemical cycles of carbon, sulfur, and strontium isotopes. Am. J. Sci. 289, 390-410. 

Figure 14 The simplified geochemical cycles of carbon and sulfur, including burial and weathering of sedimentary carbonates, organic matter, evaporites, and sulfides. The relative fluxes of burial and weathering of organic matter and sulfide minerals plays a strong role in controlling the concentration of atmospheric O2.

Walker J. C. G. (1979) The early history of oxygen and ozone in the atmosphere. Pure Appl. Geophys. 117, 498-512. Walker J. C. G. (1986) Global geochemical cycles of carbon, sulfur, and oxygen. Mar. Geol. 70, 159-174. 

While sulfate reduction has claimed the most attention by earth scientists, assimilatory organisms also reduce less oxidized forms of sulfur and may thus play a wider role in the geochemical cycling of sulfur than at present... 

We can share the view of some authors (Fenchel et al., 1998) that this theory may serve a plausible explanation of thioester world as precursor for the present RNA world. Furthermore, it is attractive in a number of respects too. One has to mention the development of very early, global scale geochemical cycling of carbon, sulfur, and iron. It would present the early interactions between atmosphere and biochemical processes, like thioester-bounded hydrogen production contribution to the formation of reducing species that were critical for any atmospheric organic synthesis. 

Of the major volatile elements described above, water, a variety of carbon compounds, nitrogen and sulfur are the volatile compounds which dominate in the modern Earth. In this section we review the modern-Earth geochemical cycles for water, carbon, nitrogen, and sulfur and look in some detail at volatile mass balances between the Earth s surface reservoirs and the deep Earth. Then, having established how the modern Earth works we seek to determine how these geochemical cycles might have operated in the early Earth. 

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