The Stable Isotope Biogeochemistry of O 2 Application and Future Directions

1. The Stable Isotope Biogeochemistry of O2 Application and Future Directions Nathaniel E. Ostrom Dept. of Zoology Biogeochemistry Environmental Research Initiative Michigan State University Cyanobacterial bloom in Lake Erie

2. A d18O-O2 Primer • The Conc. and d18O of O2 is controlled by three processes: • Atm. Exchange (G) [O2] = 100% d18O = 0.7 ‰ • Respiration (R): [O2] < 100% d18O > 0.7 ‰ • 18O concentrated in remaining O2 • Photosynthesis (P): [O2] > 100% d18O < 0.7 ‰ • O2 derived from H2O; d18O ~ -30 ‰ • No isotopic fractionation • d18O-O2 > d18O-H2O by ~ 25 ‰ Why d18O-O2? With diurnal sampling P, R and G can be obtained “Ecosystem Metabolism”

3. The Great Lakes Lake Erie Grand Traverse Bay Lake Superior GT3 HN210 HN090 HN050

4. Ocean Metabolism: Eastern Pacific Redox Experiment: R/V Roger Revelle O N ALOHA 20 Stn. 4 Stn. 2 Stn. 3 Stn. 5 Stn. 6 9 mM O2 at 400 m 10 O W 160 150 140 130 120 110 100

5. R.V. Revelle U.S. Navy: “…recommends unit immediately cease operations and head northerly at max speed…”

6. Hurricane Carlotta O2 Dynamics Before During After P G R Before After During

7. Instrumentation at the MSU Laboratory for Biogeochemistry and Paleoproteomics GVI Prism: GC Interface and Dual-Inlet

8. David T. Young, J. Hunter Waite, Gregory P. Miller Southwest Research Institute Space Science and Instrumentation Division San Antonio, TX Development of a Field-deployable Isotope-ratio Mass Spectrometer (FIMS) for BiogeochemistryComprised of the Trace Gas Sample Introduction System (TGSIS) and a Cycloidal Focusing Mass Spectrometer (CFMS) Integrated FIMS system Nathaniel E. Ostrom, Peggy H. Ostrom Michigan State University The Cyloidal Focusing Mass Spectrometer

9. Prototype TGSIS Chemical scrubbers GC Column and Oven Developed by Capstone Design Mechanical and Electrical Engineering Students at MSU: Ben LeVesque, Don Restauri, Adam Brannan, Joe Trzemzalski, Paul Strefling, Dave Biegas, Matt Jennings, and Darren Ghiso He Reservoir

10. Instrument Objectives: J-ROVER eddy covariance system of Jiquan Chen (above) and automated trace gas flux system at the KBS LTER (right). • Targeting isotopes of CO2 and N2O for • atm-biosphere monitoring networks • Overall goal to place instruments in the field • to capture episodic production events Membrane Inlet Mass Spectrometer

11. In situ mass spectrometry on Saturn's moon Titan: Impact crater River Drainages

13. Thank you!