Skidaway Institute of Oceanography

B.A. Chemistry, The College of Wooster, Wooster, Ohio, 1970
M.S. Chemistry, University of Washington, 1972
Ph.D. Chemistry, University of Washington, 1976

Local Pages:

Organic Biogeochemistry Lab Webpage

Research Interests and Projects

My research focuses on the biogeochemistry of organic matter, with an emphasis on lipid biomarkers, in aquatic environments. Lipid biomarkers provide a link between biological sources of organic matter and organic compounds preserved in sediments. Biomarkers are used as tracers of processes that produce, transport, and alter organic matter in water columns and sediments, and we use biomarker distributions to determine rates and mechanisms for these processes. Most biomarkers in the ocean are produced by phytoplankton in surface waters via photosynthesis, although terrigenous biomarkers in deep-sea sediments verify that organic compounds from continental sources also reach the sea. The fate of organic compounds is affected by biological food web dynamics, by chemical alteration such as photolysis, by association with mineral particles, and by physical transport by currents. Although most work in our laboratory is directed at understanding the behavior of biogenic organic substances, organic pollutants are affected by the same processes.

Understanding the behavior of organic substances in rivers, lakes, estuarine salt marshes, and coastal and open ocean areas is vital because organic matter is intimately involved in life processes on Earth. Biogeochemical cycling of organic matter is a major determinant of the composition of the global atmosphere and ocean: the photosynthetic production of organic matter produces oxygen and consumes carbon dioxide, while the degradation of organic matter utilizes oxygen and releases carbon dioxide. Preservation of organic matter in sediments provides a link to ancient environments, including those environments and geological processes that produce coal and oil that are critical sources of energy in today's society. If we can better understand how biogenic compounds behave in aquatic environments, we may better be able to predict the fate of pollutants, and vice versa.

Courses

Coastal Oceanography and Marine Field Methods, Skidaway Institute of Oceanography
Contaminated Sediment Geochemistry - CE8103H, Georgia Institute of Technology

Selected Publications


2009	F. Schubotz, S. G. Wakeham, J. S Lipp, H. S. Fredericks, K.-U. Hinrichs. (2009) Detection of microbial biomass by intact polar membrane lipid analysis in the water column and surface sediments of the Black Sea . Environ. Microbiol., in press.
2009	S. G. Wakeham , C. Lee, M. L. Peterson, Z. Liu, J. Szlosek, I. F. Putnam and J. Xue. (2009) Organic biomarkers fluxes in the twilight zone – Time series and settling velocity sediment traps during MedFlux. Deep-Sea Res. II, in press. doi:10.1016/j.dsr2.2008.11.030.
2009	J.-F. Rontani, N. Zabeti , and S. G, Wakeham. (2009) The fate of marine lipids: biotic vs. abiotic degradation of particulate sterols and alkenones in the Northwestern Mediterranean Sea . Mar. Chem., 113: 9-18. doi:10.1016/marchem.2008.11.001.
2009	Z. Liu, J. Mao, M. L. Peterson, C. Lee, S. G. Wakeham, and P. G. Hatcher. (2009) Characterization of sinking particles from the northwest Mediterranean Sea using advanced solid-state NMR. Geochim. Cosmochim. Acta, 73: 1014-1026. doi:10.1016/j.gca.2008.11.019.
2008	T. P. Sampere, T. S. Bianchi, S. G. Wakeham, M. A. Allison. (2008) Sources of organic matter in surface sediments of the Louisiana continental margin: effects of primary depositional/transport pathways and Hurricane Ivan. Cont. Shelf Res. 28: 2472-2487. doi:10.1016/j.csr.2008.06.009.
2007	M. Goutx, S. G. Wakeham, C. Lee, M. Duflos, C. Guigue, Z. Liu, B. Moriceau, R. Sempéré, M. Tedetti, and J. Xue. (2007) Composition and degradation of marine particles with different settling velocities in the Northwestern Mediterranean Sea . Limnol. Oceanogr. 52: 1645-1654.
2007	S. G. Wakeham, R. Amann, K. H. Freeman, E. C. Hopmans, B. B. Jørgensen, I. F. Putnam, S. Schouten, J. S. Sinninghe Damsté, H. A. Talbot, and D. Woebken. (2007) Microbial ecology of the stratified water column of the Black Sea as revealed by a comprehensive biomarker study. Org. Geochem., 38: 2070-2097.
2007	M. J. L. Coolen, B. Abbas, J. van Bleiswijk, E. C. Hopmans, M. M. M Kuypers, S. G. Wakeham, and J. S. Sinninghe Damsté. (2007) Putative ammonia-oxidizing Crenarchaeota thrive in suboxic waters of the Black Sea: A basin-wide ecological study using 16S ribosomal and functional genes and membrane lipids. Environ. Microbiol. 9, 1001-1016.
2007	A. Jaeschke, E. C. Hopmans, S. G. Wakeham, S. Schouten and J. S. Sinninghe Damsté. (2007) The presence of ladderane lipids in the oxygen minimum zone of the Arabian Sea indicate nitrogen loss through anammox. Limnol. Oceanogr. 52, 780-786.
2006	C. J. Schubert, M. J. L. Coolen, L. N. Neretin, A. Schippers, B. Abbas, E. Durisch-Kaiser, B. Wehrli, E. C. Hopmans, J. S. Sinninghe Damsté, S. Wakeham, and M. M.M. Kuypers. (2006) Aerobic and anaerobic methanotrophs in the Black Sea water column. Environ. Microbiol. Doi:10.1111/j.1462-2920.2006.01079x.
2006	X. Lin, S. G. Wakeham, I. F. Putnam, Y. M. Astor, M. I. Scranton, A. Y. Chistoserdov and G. T. Taylor. (2006) Comparison of vertical distributions of prokaryotic assemblages in the anoxic Cariaco Basin and Black Sea by use of fluorescence in situ hybridization. Appl. Environ. Microbiol. 72: 2679-2690.
2006	S. G. Wakeham, A. P. McNichol, J. Kostka, T. K. Pease. (2006) Natural abundance radiocarbon as a tracer of assimilation of petroleum carbon by bacteria in salt marsh sediments. Geochim. Cosmochim. Acta. 70: 1761-1771.
2004	C. Lee, S. G. Wakeham and C. Arnosti. (2004) Particulate organic matter in the sea: the composition conundrum. Ambio 33: 565-575.