William T. Anderson
Assistant Professor
Doctor of Natural Sciences, Swiss Federal Institute of Technology (ETH-Zürich), 2000
M.S. Syracuse University, 1995
B.A. University of Kansas, 1992

Office: PC 342B
Laboratory: QSL PC 305, SIL OE 310
Telephone: (305) 348-2693/7475/3044
Email: andersow@fiu.edu

Stable Isotope Biogeochemsitry and Paleoclimatology
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Research Interests
My current research focuses on the oxygen, carbon, and nitrogen isotopic signature in organic material. This work/approach is focused on the calibration and reconstruction of the isotopic hydrologic cycle from terrestrial archives (tree rings and lake sediments) located in the US, Europe, and South America. Present work focuses on applying new continuous flow isotope ratio mass spectrometry (CF-IRMS) methods to biogeocemical orientated projects in the Everglades, The Keys, Florida Bay, and other tropical locations in South America. The goal of this approach is to better understand how changes in the hydrologic cycle and environmental conditions (nutrients, pCO2, stress, etc.) affect different biogeochemical systems, which aids in improving our understanding of past and present climatic change.

The SERC Stable Isotope Laboratory (http://www.fiu.edu/~sil) is equipped with three mass spectrometers including: a Finnigan deltaC EA-IRMS, a Finnigan deltaPlus GC-IRMS, and a Micromass Prism with both duel inlet and continuous flow EA modes. The laboratory can measure all important stable isotopes (C,N,S, and O), in a variety of inorganic and organic compounds.

Current research projects include:

South Florida Marine Stable Isotope Time Series
Understanding nitrogen and carbon isotopic signals from organic matter in modern systems with implications for geologic records (funded by ACS PRF-38095-G2). Samantha Evans (Doctoral Student) has just completed her first year of quarterly POM sampling at 6 stations in the Florida Keys National Marine Sanctuary and Florida Bay. This work is being done in conjunction with the Seagrass Lab (directly by James Fourqurean) and the FCE-LTER.

Seagrass History of Florida Bay, Everglades National Park
FIU geologists, biologists and chemists are investigating the amount of variation in coastal environmental conditions that is naturally occurring. Our approach is to reconstruct the historical record of seagrass abundance, which is highly correlated with environmental water quality. We have collected sediment cores and obtained ages as old as 4000+ years, and we are using proxies of seagrass abundance contained in the sediment as indicators of the environmental water quality of the past few hundred years. I am studying seagrass-associated foraminifera as an indicator of seagrass abundance, and will combine my results with the other proxies (sedimentology, geochemistry, diatoms) to produce an integrated history of Florida Bay seagrass abundance.

Isotopic signals in Tropical and semi-Tropical tree
Our recent work in Brazil and South Florida have shown it is possible to two work with and find ring forming species in low latitude areas with strong seasonal wet/dry periods. We are now working on water-level reconstructions in wetlands systems using stable isotopes. This work is being done in conjunction with the Leo Sternberg at the University of Miami.

Limnogeolgy - The geologic study of lakes as archives of climate change
Recently the group has started to focus on Quaternary Research with the opening of the Quaternary Science Laboratory, which is equiped several lake core systems and sample modern sample processing systems. In the past we have work with groups at Syracuse on Lake Ontario and with Matt Kirby at CalState Fullerton on Lake Elsinore. Presently we have two funded projects studying paleoclimate and paleoecological archives in lakes and peat bogs: 1) Sediment nutrient characteristics and paleolimnological reconstruction of Lake Monroe, Florida, USA, (with Gaiser and Scinto, both at FIU), funded by the St. John's River Water Management District; and 2) Lynch's Crater, Queensland: A terrestrial climate record of the past 200,000 years as a key to understand modern climatic fluctuations, with Wust and Kershaw (both at James Cook Uni., Australia), funded by Australian Research Council.

Recent publications:

Wozniak, J.R., Childers, D.L., Anderson, W.T., Rudnick, D.T., and Madden, C.J., 2008, An in situ mesocosm method for quantifying nitrogen cycling rates in oligotrophic wetlands using 15N tracer techniques: Wetlands, v. 28, n. 2, p. 502-512.

Muller, J., Kylander, M., Wüst, R.A.J., Weiss, D., Martinez-Cortizas, A., LeGrande, A. N., Jennerjahn, T., Behling, H., Anderson, W.T., Jacobson, G, 2008, Possible evidence for wet Heinrich phases in tropical NE Australia: The Lynch’s Crater deposit: Quaternary Science Reviews, v. 27, p. 468-475.

Sternberg. L.S.L., Pinzon, M.C., Vendramini, P., Anderson, W.T., Jahren, H., and Beuning, K., 2007, Oxygen isotope ratios of cellulose-derived phenylglucosazone: An improved paleoclimate indicator of environmental water and relative humidity: Geochimica et Cosmochimica Acta, v. 71, p. 2463-2473.

Sternberg, L, Pinzon, M.C., Anderson, W.T., and Jahren, A.H., 2006, Variation in oxygen isotope fractionation during cellulose synthesis: Molecular and biosynthetic effects: Plant, Cell and Environment. v. 29, p. 1881-1889.

Evans, S.L., Anderson, W.T., and Jochem, F.J., 2006, Spatial variability in Florida Bay particulate organic matter composition: combining flow cytometry with stable isotope analyses: Hydrobiologia, v. 569, p. 151-165.

Fourqurean, J.W., Escoria, S.P., Anderson, W.T., and Zieman, J., 2005, Spatial and seasonal variability in elemental content, d13C and d15N of Thalassia testudinum from south Florida and its implications for ecosystem studies: Estuaries, v. 28, n. 3, p. 447-461.

Anderson, W.T., Sternberg, L., Pinzon, M.C., Gann-Troxler, T., Childers, D.L., and Duever, M., 2005, Carbon isotope composition of cypress trees from South Florida and changing hydrologic conditions: Dendrochronologia, v. 23, n. 1, p. 1-10.