Evolution of Carbon and Sulfur Biogeochemical Cycles

Specifically, the isotopic composition of the carbon compounds in the oldest sediments supports the conclusion that the geochemical cycle of carbon evolved into a biogeochemical cycle by the time of the deposition of these rocks. Thus, a fully developed biogeochemical carbon cycle may date from 3.8 billion years ago. Also, the morphological record of microbial (prokaryotic) life has been shown to proceed over at least 3.5-3.8 billion years of geological history. 

The geochemical balance of carbon changed dramatically during Devonian and Carboniferous times. At those times the main evolutionary radiation of terrestrial vascular plants occurred. These events flowed from the development of various parts of higher plants, such as roots, stems, leaves, and reproductive apparatus enabling the colonization of a new ecological niche. This colonization and accumulation of 

No remarkable alterations were shown in carbon and sulfur cycles or in atmospheric oxygen concentrations since the Latest Proterozoic. The coupling of carbon and sulfur biogeochemical cycles is supported by systematic covariations in the isotopic records of sedimentary rocks over Phanerozoic time. 

The appearance of photosynthetic system II and the consequent rise in atmospheric oxygen content would have also changed significantly the geochemical cycles of ferric iron and hydrogen during the Archean and much of the Proterozoic times. 

In addition to carbonate precipitation, the introduction ofC02-fixing organisms into the surficial environment must have a paramount impact on the terrestrial carbon cycle 

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What are the similarities in the evolution of carbon and sulfur biogeochemical cycling Give examples of biological processes that possess these cycles. 

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