HR: 10:30h
AN: H22A-01 INVITED     [Abstracts]
TI: Ecohydrology Applications of Atmospheric Stable Isotope Measurements via Tunable Diode Laser Absorption Spectroscopy
AU: * mcdowell, N
EM: mcdowell@lanl.gov
AF: Los Alamos National Laboratory, EES-2, MSJ495, Los Alamos, NM 87545 United States
AB: The stable carbon isotope composition of plant organic matter has commonly been used as an index of plant carbon-water balance, or water-use efficiency, for decades. Likewise, the oxygen isotope composition of plant organic matter has been used for understanding the interaction between climate, water source and physiology. The carbon and oxygen stable isotope composition of atmospheric carbon dioxide is recently being used to understand ecosystem-scale patterns and controls over the interaction of climate and the carbon and water cycles. However, sampling limitations have made such investigations costly both in time and finances, prohibiting extensive, continuous data sets. A new technique, Tunable Diode Laser Absorption Spectroscopy (TDLAS), allows continuous monitoring of the carbon and oxygen isotope composition of atmospheric carbon dioxide at one-minute resolution, thereby dramatically broadening the opportunities to study the patterns and controls over ecohydrologic functions of terrestrial ecosystems. This talk will describe TDLAS methodology, applications, and recent results from an ongoing ecohydrology study of a pinon-juniper woodland.
DE: 0315 Biosphere/atmosphere interactions
DE: 0400 Biogeosciences
DE: 1818 Evapotranspiration
SC: Hydrology [H]
MN: 2005 Joint Assembly