@article {585,
	title = {Natural-abundance radiocarbon as a tracer of assimilation of petroleum carbon by bacteria in salt marsh sediments},
	journal = {Geochimica Et Cosmochimica Acta},
	volume = {70},
	year = {2006},
	note = {030olTimes Cited:27Cited References Count:65},
	month = {Apr 1},
	pages = {1761-1771},
	abstract = {The natural abundance of radiocarbon ((14)C) provides unique insight into the source and cycling of sedimentary organic matter. Radiocarbon analysis of bacterial phospholipid lipid fatty acids (PLFAs) in salt-marsh sediments of southeast Georgia (USA)-one heavily contaminated by petroleum residues-was used to assess the fate of petroleum-derived carbon in sediments and incorporation of fossil carbon into microbial biomass. PLFAs that are common components of eubacterial cell membranes (e.g., branched C(15) and C(17), 10-methyl-C(16)) were depleted in (14)C in the contaminated sediment (mean Delta(14)C value of +25 +/- 19 parts per thousand for bacterial PLFAs) relative to PLFAs in uncontaminated "control" sediment (Delta(14)C = +101 +/- 12 parts per thousand). We suggest that the (14)C-depletion in bacterial PLFAs at the contaminated site results from microbial metabolism of petroleum and subsequent incorporation of petroleum-derived carbon into bacterial membrane lipids. A mass balance calculation indicates that 6-10\% of the carbon in bacterial PLFAs at the oiled site could derive from petroleum residues. These results demonstrate that even weathered petroleum may contain components of sufficient lability to be a carbon source for biomass production by marsh sediment microorganisms. Furthermore, a small but significant fraction of fossil carbon is assimilated even in the presence of a much larger pool of presumably more-labile and faster-cycling carbon substrates. (c) 2006 Elsevier Inc. All rights reserved.},
	issn = {0016-7037},
	doi = {10.1016/j.gca.2005.12.020},
	author = {Wakeham, S. G. and McNichol, A. P. and Kostka, J. E. and Pease, T. K.}
}
