Special emphasis on fossil materials, fossil fuel origin and migration, early diagenesis of organic matter, abyssal ocean cycling of carbon and nitrogen, abiotic synthesis of organic materials and organic pollutants. Molecular approaches to isotope analysis. Isotope studies of food webs in modern and fossil ecosystems. Resolution of diet in early humans.

Selected Recent Publications

Brisman, K., M. H. Engel and S. A. Macko. 2001. Distribution, stereochemistry, and stable isotope composition of amino acids in K/T boundary sediments. Precambrian Research 106:59-78.

Chambers, R.M., J.W. Fourqurean, S.A. Macko and R.Hoppenot. 2001. Biogeochemical effects of iron availability on primary producers in a shallow marine carbonate environment. Limnol Oceanogr 46:4278-4286.

Engel, M.H. and S.A. Macko. 2001. The stereochemistry of amino acids in the Murchison meteorite. Precambrian Research 106:35-46.

Fryer, A. E., W.F. Mullican and S.A. Macko. 2001. Chemical evolution during recharge to and flow within the High Plains aquifer, Texas. Hydrolog Journal.

Haramis, G. M., D.G. Jorde, J.L. Walker and S.A. Macko. 2001. A stable isotope analysis of canvasback winter diet in upper Chesapeake Bay. Auk 118:1008-1017.

Knoff, A., S.A. Macko and M. Erwin. 2001. Diets of nesting laughing gulls (Larus atricilla) at the Virginia Coastal Reserve: Observations from stable isotope analysis. Isotopes Environm Health Stud 37:67-88.

MacAvoy, S., S.A. Macko and G. Garman. 2001. Isotope turnover in aquatic predators: Quantifying the exploitation of migratory prey. Canadian J. Fisheries Aqautic Sci 58:923-932.

Schidlowski, M., M.H. Engel and S.A. Macko. 2001. From Sediments to Meteorites: A Special Issue in Memory of Bartholomew Nagy. Precambrian Research 106:1-186, Elsevier, Amsterdam.

Sigleo, A.C. and S.A. Macko. 2001. Carbon and nitrogen isotopes in suspended particles and colloids, Chespeake and San Francisco Estuaries, U.S.A. Estuarine and Coastal Shelf Science, 54:701-711.

Tobias, C.R., I. Anderson, E. Canuel and S.A. Macko. 2001. Nitrogen cycling through a fringing marsh- aquifer ecotone. Marine Ecol Progress Series 210:25-39.

Tobias, C.R., S.A. Macko, I.C. Anderson, E.A. Canuel and J.W. Harvey. 2001. Tracking the fate of a high concentration.groundwater nitrate plume through a fringing marsh: A combined groundwater tracer and in situ isotope enrichment study. Limnol Oceanogr 46:1977-1989.

Townsend, M.A., S.A. Macko and D.P. Young. 2001. Distribution and sources of nitrate-nitrogen in Kansas groundwater. The Scientific World 1:216-222.

Turekian, V.C., S. A. Macko, and W.C. Keene. 2001. Application of stable sulfur isotopes to differentiate sources of size-resolved particulate sulfate in polluted marine air at Bermuda during spring. Geophysical Research Letters 28:1491-1494.

Anderson, I.C., C.R. Tobias, S.A. Macko and M.A. Poth. 2000. Sources and sinks of nitrogen in acidified glacial lakes of the Bohemian Forest, Czech Republic. Silva Gabreta 4:135-146.

Bytnerowicz, A., S. Godzik, M. Poth, I. Anderson, J.Szduj, C. Tobias, S. A. Macko, P. Kubiesa, T. Stazewski and M. Fenn. 2000. Chemical composition of air, soil and vegetation in forests of the Silesian Beskid Mountains, Poland. Water, Air and Soil Pollution 116:141-150.

Fisher, C.R., I.R. MacDonald, R. Sasson, C.M. Young, S.A. Macko, S. Hourdez, R.S. Carney, S. Joye, and E. McMullin. 2000. Methane ice worms: Hesiocaeca methanicola colonizing fossil fuel reserves. Naturwissenschaften 87:184-187.

Fryer, A.E., S.A. Macko, W.F. Mullican, K.D. Romanak and P.C. Bennet. 2000. Nitrate during ground-water recharge, southern high plains, Texas. J. Contam. Hydrol. 40:335-363.

Goodfriend, G. A., M. J. Collins, M. L. Fogel, S. A. Macko, and J. F. Wehmiller (eds.). 2000. Perspectives in Amino Acid and Protein Geochemistry. Oxford University Press, NY. vi+366p.

Hobbie, E., S.A. Macko and M. Williams. 2000. Correlations between foliar d15N and nitrogen concentrations may indicate plant-mycorrhizal interactions. Oecologia 122:273-283.

Korontzi, S., S. A. Macko, I.C. Anderson and M.A. Poth. 2000. A stable isotopic study to determine carbon and nitrogen cycling in a disturbed southern Californian forest ecosystem. Global Biogeochem. Cycles 14:177-188.

MacAvoy, S.E., S.A. Macko, S.P. McInich and G.C. Garman. 2000. Marine nutrient contributions to freshwater apex predators. Oecologia 122:568-573.

Nissenbaum, A., S.A. Macko and M.H. Engel. 2000. The isotopic composition of hair from archaeological sites in Israel. Archaeology and Science 7:27-30 (in Hebrew).

Spangenberg, J.E., L. Fonbote and S.A. Macko. 2000. An evaluation of the inorganic and organic geochemistry of the San Vicente Mississippi Valley-type zinc-lead district, central Peru: implications for ore composition, mixing processes, and sulfate reduction. Econom. Geol. 94:1067-1092.

Bytnerowicz A., S. Godzik, M. Poth, I. Anderson, J. Szdzuj, C. Tobias, S. Macko, P. Kubiesa, T. Staszewski, and M. Fenn. 1999. Chemical composition of air, soil and vegetation in forests of the Silesian Beskid Mountains, Poland. Water, Air, & Soil Pollution 116:141-150.

Hobbie, E.A., S.A. Macko and H.H. Shugart. 1999. Insights into nitrogen and carbon dynamics of ectomycorrhizal and saprotrophic fungi from isotopic evidence. Oecologia 118:353-360.

Hobbie EA., S.A. Macko and H.H. Shugart. 1999. Interpretation of nitrogen isotope signatures using the NIFTE model. Oecologia. 120:405-415.

Macko, S.A. and M.H. Engel. 1999. Organic matter in fossils. Pages 456-458 In: Encyclopedia of Geochemistry. Marshall, C.P. and Fairbridge, R.W., eds. Kluwer Acad. Pub., Boston, MA.

Macko, S.A., G. Lubec, M. Teschler-Nicola, V. Andrusevich and M.H. Engel. 1999. The Ice Man’s diet reflected by the stable nitrogen and carbon isotopic composition of his hair. Federation of American Societies for Experimental Biology Journal 13:559-562.

Macko, S.A., M.H. Engel, V. Andrusevich, G. Lubec, T.C. O’Connell and R.E.M. Hedges. 1999. Documenting the diet in ancient human populations through stable isotope analysis of hair. Phil. Trans. Royal Society 353:1-12.

Pope, J., T.H. O’Donnell, S.A. Macko and D. Rosen. 1999. Use of stable isotopes for tracking Anaragonite beach fill. Coastal Sediments 99, ASCE, NY, pp 1-15.

Scott, K.M., M. Bright, S.A. Macko, and C.R. Fisher. 1999. Carbon dioxide use by chemoautotrophic endosymbionts of hydrothermal vent vestimentiferans: Affinities for carbon dioxide, absence of carboxysomes, and d13C values. Mar. Biol. 135:24-34.

Uhle M.E., S.A. Macko, H.J. Spero, D.W. Lea, W.F. Ruddiman, and M.H. Engel. 1999. The fate of nitrogen in the Orbulina universa foraminifera-symbiont system determined by nitrogen isotope analyses of shell-bound organic matter. Limnology & Oceanography 44:1968-1977.

Walker, J.L., S.A. Macko and C.W. Potter. 1999. Stable isotopes correlate the diets of modern and historic bottlenose dolphin populations. Mar. Mammal Res. 15:335-350.

Walker, J.L. and S.A. Macko. 1999. The correlation of diets of marine mammals with stable isotopic analyses of teeth. Mar. Mammal Res. 15: 314-334.

Engel, M.H. and S.A. Macko, 1997. Isotopic evidence for extraterrestrial nonracemic amino acids in the Murchison meteorite. Nature 389:265-268.

Macko, S.A., M.E. Uhle, M.H. Engel and V. Andrusevich, 1997. Stable nitrogen isotope analysis of amino acid enantiomers by gas chromatography/combustion/isotope ratio mass spectrometry. Analytical Chemistry 69:926-929.