Tracing changes in ecosystem function under elevated CO₂

Conference · Tue Dec 31 04:00:00 EST 2002

OSTI ID:1178618

Pataki, D E. ^[1]; Ellsworth, David; Evans, R. D.; Gonzalez-Meler, M.; King, J.; Leavitt, S. W.; Matamala, R.; Pendall, D. E.; Siegwolf, R.; van Kessel, C.; Ehleringer, J. R.

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1. University of Michigan, School of Natural Resources

Carbon, nitrogen, oxygen, and hydrogen isotope ratios at natural abundance levels provide valuable tracers for integrated analyses in high-CO₂ experiments of terrestrial ecosystems. The additional CO₂ supplied in these experiments provides a very useful label that can be used to trace carbon flows and turnover rates in different pools, both under elevated CO₂ treatment conditions as well after completion of the long-term experiment when the supplemental CO₂ is turned off. In experiments where isotope ratio mass spectrometry is not available, archival of dry biomass and soil samples can provide opportunities for future isotope analysis of organic matter. Frozen leaf and soil samples, or if possible water extracted and stored in sealed head space vials, can provide valuable information regarding the effect of elevated CO₂ on the leaf water budget and possibly on the leaf energy balance. Linking these stable isotope analyses with traditional approaches in elevated CO₂ ecosystem studies provides a unique opportunity for tracing short-term and long-term changes in the carbon cycle and its impacts on the nitrogen cycle, the water cycle, and trophic-level interactions.

• Research Organization: Duke University, Durham, NC (US)
• Sponsoring Organization: USDOE Office of Energy Research (ER)
• DOE Contract Number: FG02-01ER63184
• OSTI ID: 1178618
• Country of Publication: United States
• Language: English