DOI
https://doi.org/10.25772/HV6B-QV41
Defense Date
2023
Document Type
Thesis
Degree Name
Master of Science
Department
Biology
First Advisor
Dr. Scott Neubauer
Abstract
Tidal freshwater marshes have preserved substantial stocks of soil carbon, which represents carbon dioxide that is no longer in the atmosphere. There is conflicting evidence in the literature about how disturbances such as sea level rise and associated wetland salinization impact the accumulation and long-term stability of this stored carbon. The goal of this experiment was to quantify how salinization impacts total ecosystem respiration and its component parts, autotrophic and heterotrophic respiration. This was a microcosm experiment using a C4 plant (Spartina cynosuroides) grown in soil derived from C3 plant matter and exposed to different salinities (0 to 9 psu). Results indicate that higher levels of salinization changed total ecosystem respiration. The highest salinity caused a decrease in belowground plant biomass and increased aboveground leaf mortality, although aboveground biomass was similar to other treatments. There were some issues with the isotope data, and several of the calculated autotrophic respiration measurements were impossible. These data are reviewed in the Appendix. The results from this study help shed light on changes in carbon fixation and subsequent biomass accumulation in stressed wetland ecosystems. This is a matter of great concern if it is not at a rate that keeps up with sea level rise.
Rights
© The Author
Is Part Of
VCU University Archives
Is Part Of
VCU Theses and Dissertations
Date of Submission
5-8-2023