HR: 1340h
AN: PP43B-1269    [Abstracts]
TI: Bulk and Compound-Specific Isotope Analysis of Long-Chain, n-alkanes From a 85-kyr Core From Lake Peten Itza, Guatemala
AU: * Mays, J L
EM: jlmays@ufl.edu
AF: Department of Geological Sciences and Land Use and Environmental Change Institute (LUECI), University of Florida, 241 Williamson Hall, P.O. Box 112120, Gainesville, FL 32611, United States
AU: Brenner, M
EM: brenner@ufl.edu
AF: Department of Geological Sciences and Land Use and Environmental Change Institute (LUECI), University of Florida, 241 Williamson Hall, P.O. Box 112120, Gainesville, FL 32611, United States
AU: Bush, M B
EM: mbush@fit.edu
AF: Department of Biological Sciences, Florida Institute of Technology, 150 W. University Boulevard, Melbourne, FL 32901, United States
AU: Correa, A
EM: acorrea@fit.edu
AF: Department of Biological Sciences, Florida Institute of Technology, 150 W. University Boulevard, Melbourne, FL 32901, United States
AU: Curtis, J H
EM: curtisj@ufl.edu
AF: Department of Geological Sciences and Land Use and Environmental Change Institute (LUECI), University of Florida, 241 Williamson Hall, P.O. Box 112120, Gainesville, FL 32611, United States
AU: Hodell, D A
EM: hodell@ufl.edu
AF: Department of Geological Sciences and Land Use and Environmental Change Institute (LUECI), University of Florida, 241 Williamson Hall, P.O. Box 112120, Gainesville, FL 32611, United States
AB: Drill cores obtained from Lake Petén Itzá, Guatemala, contain a ~85-kyr record of terrestrial climate from lowland Central America. Variations in sediment lithology suggest rapid changes in precipitation during the last glacial and deglacial periods. Previous work in nearby Lake Quexil demonstrated the utility of using the carbon isotopic compositions of leaf wax n-alkanes to infer changes in terrestrial vegetation (Huang et al., 2001). Here we report carbon isotopes of bulk organic and long-chain n-alkanes in 60 samples to reconstruct changes in the relative proportion of C₃ and C₄ biomass in the watershed under changing climate and atmospheric CO₂ conditions during the past 85 kyrs. Compound-specific carbon isotope results are compared directly with pollen analysis from the same samples. Huang, Y., F.A. Street-Perrott, S.E. Metcalfe, M. Brenner, M. Moreland, and K.H. Freeman. 2001. Climate change as the dominant control on glacial-interglacial variations in C₃ and C₄ plant abundance. Science 293:1647-1651.
DE: 0746 Lakes (9345)
DE: 1041 Stable isotope geochemistry (0454, 4870)
DE: 3344 Paleoclimatology (0473, 4900)
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2007 Fall Meeting