Abstract:
:Concentrations and isotopic compositions of ethane and propane in cold, deeply buried sediments from the southeastern Pacific are best explained by microbial production of these gases in situ. Reduction of acetate to ethane provides one feasible mechanism. Propane is enriched in (13)C relative to ethane. The amount is consistent with derivation of the third C from inorganic carbon dissolved in sedimentary pore waters. At typical sedimentary conditions, the reactions yield free energy sufficient for growth. Relationships with competing processes are governed mainly by the abundance of H(2). Production of C(2) and C(3) hydrocarbons in this way provides a sink for acetate and hydrogen but upsets the general belief that hydrocarbons larger than methane derive only from thermal degradation of fossil organic material.
journal_name
Proc Natl Acad Sci U S Aauthors
Hinrichs KU,Hayes JM,Bach W,Spivack AJ,Hmelo LR,Holm NG,Johnson CG,Sylva SPdoi
10.1073/pnas.0606535103subject
Has Abstractpub_date
2006-10-03 00:00:00pages
14684-9issue
40eissn
0027-8424issn
1091-6490pii
0606535103journal_volume
103pub_type
杂志文章abstract::The Hawaiian Islands are renowned for some of the most spectacular species radiations in the world. Most of these radiations have been attributed to single colonization events, although the evidence supporting monophyletic origins is often poorly resolved and/or ambiguous. Without a concrete understanding of the origi...
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1980-09-01 00:00:00