2023 Early Hearing Detection & Intervention Conference
March 5-7, 2023 • Cincinnati, OH
5/23/2019 | 2:45 PM - 3:00 PM | DIEL VARIATION IN THE STABLE ISOTOPE SIGNATURE OF CO2 IN PRODUCTIVE STREAMS | 251 AB
DIEL VARIATION IN THE STABLE ISOTOPE SIGNATURE OF CO2 IN PRODUCTIVE STREAMS
Dissolved carbon dioxide (CO2) dynamics in streams are the product of multiple biogenic, geogenic, and atmospheric sources and processes. Spatial variation in the isotopic signature of CO2 (13C-CO2) has been used to attribute CO2 to different sources, but diel temporal variation in 13C-CO2 has rarely been used to separate variation catchment sources of CO2 from in-stream CO2 production and consumption. Here we continuously monitored dissolved oxygen, CO2, pH, and temperature with sensors and used discrete water samples for analysis of 13C-CO2, alkalinity, and dissolved inorganic carbon (DIC) over four, 24 h periods in three streams in Montana and Arizona, USA. Diel variation in CO2 ranged up to 19.8 mmol CO2 L-1 and 4.9 ‰ 13C-CO2 with the highest concentrations of CO2 and the most depleted 13C at night. We report how estimates of gross primary productivity and ecosystem respiration vary among models which incorporate CO2 isotopes and use asynchrony in the timing of CO2 and 13C-CO2 to inform our understanding of in-stream carbon transformations. Modeling diel variation in stable C-CO2 isotopes can help our understanding of how whole-stream metabolic rates that influence stream carbon storage, transformation, and transport.
- Isotope
- Primary Production
- Metabolism
Presentation:
This presentation has not yet been uploaded.
Handouts:
Handout is not Available
Transcripts:
CART transcripts are NOT YET available, but will be posted shortly after the conference
Presenters/Authors
Joanna Blaszczak
(), Global Water Center and Department of Natural Resources and Environmental Science, University of Nevada, Reno, jblaszczak@unr.edu;
ASHA DISCLOSURE:
Financial -
Nonfinancial -
Robert O. Hall
(), Flathead Lake Biological Station, University of Montana, bob.hall@flbs.umt.edu;
ASHA DISCLOSURE:
Financial -
Nonfinancial -