Global patterns in leaf 13C discrimination and implications for studies of past and future climate
- A. Diefendorf, K. Mueller, S. Wing, P. Koch, K. Freeman
- Environmental ScienceProceedings of the National Academy of Sciences
- 15 March 2010
A 4.6‰ decline in the δ13C of atmospheric CO2 is estimated at the onset of the Paleocene-Eocene Thermal Maximum, an abrupt global warming event ∼55.8 Ma, leading to better constraints on past greenhouse-gas perturbations.
The Effects of Sample Treatment and Diagenesis on the Isotopic Integrity of Carbonate in Biogenic Hydroxylapatite
The study of the isotopic composition of structural carbonate in fossil vertebrate hydroxylapatite has been hampered by uncertainty concerning sample treatment and arguments about the susceptibility…
ISOTOPIC RECONSTRUCTION OF PAST CONTINENTAL ENVIRONMENTS
- P. Koch
- Environmental Science, Geography
- 1 May 1998
▪ Abstract Vertebrate fossils and continental sediments provide a rich record of variations in the isotopic composition of surface environments. To interpret these records, a greater understanding of…
Assessing the Causes of Late Pleistocene Extinctions on the Continents
- A. Barnosky, P. Koch, Robert S. Feranec, S. Wing, Alan B. Shabel
- Environmental Science, GeographyScience
- 1 October 2004
Evidence now supports the idea that humans contributed to extinction on some continents, but human hunting was not solely responsible for the pattern of extinction everywhere, and suggests that the intersection of human impacts with pronounced climatic change drove the precise timing and geography of extinction in the Northern Hemisphere.
Late Quaternary Extinctions: State of the Debate
- P. Koch, A. Barnosky
- Environmental Science, Biology
- 7 November 2006
Results from recent studies suggest that humans precipitated extinction in many parts of the globe through combined direct (hunting) and perhaps indirect (competition, habitat alteration) impacts, but that the timing and geography of extinction might have been different and the worldwide magnitude less, had not climatic change coincided with human impacts in many places.
Using stable isotope biogeochemistry to study marine mammal ecology
- S. Newsome, M. Clementz, P. Koch
- Environmental Science
- 1 July 2010
This review supplies a complete list of published SIA contributions to marine mammal science and highlights informative case examples in four general research areas: physiology and fractionation, foraging ecology and habitat use, ecotoxicology, and historic ecology and paleoecology.
Correlation between isotope records in marine and continental carbon reservoirs near the Palaeocene/Eocene boundary
- P. Koch, J. Zachos, P. Gingerich
- Environmental Science, GeographyNature
- 23 July 1992
CHANGES in the isotope content of the large marine carbon reservoir can force shifts in that of the smaller carbon pools in the atmosphere and on land. The carbon isotope compositions of marine…
A humid climate state during the Palaeocene/Eocene thermal maximum
- G. Bowen, D. Beerling, P. Koch, J. Zachos, T. Quattlebaum
- Environmental Science, GeographyNature
- 25 November 2004
The authors' results provide evidence for a previously unrecognized discrete shift in the state of the climate system during the PETM, characterized by large increases in mid-latitude tropospheric humidity and enhanced cycling of carbon through terrestrial ecosystems.
Using Isoscapes to Trace the Movements and Foraging Behavior of Top Predators in Oceanic Ecosystems
- B. Graham, P. Koch, S. Newsome, K. McMahon, D. Aurioles
- Environmental Science
- 2010
The stable isotope composition of animal tissues can provide intrinsic tags to study the foraging and migratory ecology of predators in the open ocean. Chapter 13 (this volume) demonstrated that by…
Oxygen isotope partitioning between phosphate and carbonate in mammalian apatite
- J. Bryant, P. Koch, P. Froelich, W. Showers, B. Genna
- Geography, Environmental Science
- 1 December 1996
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