High-Energy Storm Events and Their Impacts on Carbon Storage in Tidal Wetlands of South Carolina

Author

Gavin GleasmanFollow

Date of Award

8-2023

Document Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Environmental Engineering and Earth Science

Committee Chair/Advisor

Dr. Kelly Best Lazar

Committee Member

Dr. Alex Pullen

Committee Member

Dr. Cindy Lee

Committee Member

Dr. Timothy DeVol

Abstract

Atmospheric carbon dioxide (CO₂) concentrations have been increasing at an accelerating rate for the past two centuries, profoundly impacting global climate change. Atmospheric CO₂ concentrations are influenced by the global carbon cycle through physical and biogeochemical pathways. Tidal wetland environments play a vital role in the global carbon cycle by offsetting atmospheric CO₂ concentrations through their natural physiochemical processes of high autotrophic productivity, allochthonous organic matter deposition, anoxic soils, and continuous accretion which promotes carbon sequestration with long-term storage at the land-ocean margin. The Intergovernmental Panel on Climate Change (IPCC) and United States Global Change Research Program (USGCRP) identify tidal wetlands to be important environments for regulating atmospheric CO₂ concentrations; however, these climate research governing bodies also identify current CO₂ flux datasets from tidal wetlands to be lacking expansive spatial and temporal monitoring. Furthermore, the role of hurricane disturbances on the productivity of CO₂ flux and carbon storage in tidal wetlands lacks scientific consensus.

This work produced a low-cost innovative CO₂ flux monitoring method and a unique continuous long-term dataset to yield insight into tidal wetlands’ role in the carbon-climate feedback. Four key investigations of CO₂ flux in tidal wetlands were undertaken which included (1) the development and successful deployment of a low-cost, continuous long-term CO₂ flux monitoring method in a dynamic intertidal zone, (2) insight into near-annual CO₂ sequestration of 9.4 µmol m^-2 s^-1 in the North Inlet-Winyah Bay (NI-WB) tidal wetland system of SC and how the environmental conditions correlated to the CO₂ flux over the sampling period (August 2022 – May 2022), (3) a temporal determination of the 2022 Hurricane Ian’s influence on CO₂ flux in the NI-WB tidal wetlands; with sequestration pre- and during-Hurricane Ian and net emission post-Hurricane Ian, and (4) an identification of varying carbon accumulation rates (15.2-120.6 gC m^-2 yr^-1) in NI-WB with historical correlation of high-energy deposits and carbon storage capacity.

The widespread adoption of the innovative CO₂ flux monitoring methodology presented within this dissertation and the continued identification of carbon storage via sediment cores in global tidal wetlands will produce a comprehensive synthesis of the role tidal wetlands play in carbon-climate feedback. The successful investigation of tidal wetlands’ role in carbon-climate feedback will assist in refining ESM predictions of global climate change projections to ultimately inform tidal wetland management practices and climate policy.

Recommended Citation

Gleasman, Gavin, "High-Energy Storm Events and Their Impacts on Carbon Storage in Tidal Wetlands of South Carolina" (2023). All Dissertations. 3405.
https://open.clemson.edu/all_dissertations/3405

Author ORCID Identifier

0009-0007-2819-0247