PhD Dissertation Defense: Jill Arriola

The PhD Dissertation Defense of Jill Arriola will be presented by the University of North Carolina at Chapel Hill Department of Marine Sciences. The main location of this event will be in conference room 3204 on the 3rd floor of Murray/Venable Hall on UNC main-campus in Chapel Hill, NC. The defense will be streamed live to room 222 of UNC’s Institute of Marine Sciences in Morehead City, NC and online via Zoom (Meeting ID: 598-444-358). This event will be held on Monday, November 11th at 10:00 am.

Title: Variability of carbon burial and storage in salt marsh sediments under influences of human and natural disturbances across spatiotemporal scales

Abstract: Salt marshes play an important role in the global carbon cycle as reservoirs of atmospheric CO2 and are estimated to bury carbon at rates higher than other blue carbon and terrestrial ecosystems. Defining the long-term potential and capacity of salt marshes to store CO2 has become increasingly important as policy makers require more accurate estimates to implement climate change mitigation strategies while also assessing the total value of conserving these environments. Along with the growing need to improve the accuracy of carbon burial and storage estimates in salt marsh sediments, understanding how these carbon reservoirs may be altered in the face of increasing human and natural disturbances is also critically important. Salt marshes are influenced by direct and indirect physical human activities, such as increased sedimentation from upland deforestation, and the effects of climate change, such as rising sea levels, which can result in enhancement or reduction of their carbon storage. Refining the role of salt marshes in the global carbon cycle requires further understanding of the spatiotemporal variability of carbon stored in salt marsh sediments, how the use of different methods may skew our assessment of these carbon pools, and how salt marsh carbon burial and storage is influenced by a range of disturbances.
The goal of this dissertation is to enhance understanding of variability in organic carbon burial and storage in salt marsh sediments across spatiotemporal scales over differing degrees of disturbances using consistent methods. Chapters 1 and 2 investigate spatiotemporal variability of carbon storage in salt marshes along the U.S. Gulf of Mexico within different marsh maturation stages and geomorphology settings across study sites of similar latitudes. Chapter 3 examines how human-induced changes in sediment delivery influence carbon burial in abandoned and active lobes of the Yellow River delta, China. Chapter 4 identifies the impacts of Hurricane Harvey on sediment carbon quality and quantity in Texas salt marshes. The results of this dissertation research will help further our understanding of salt marsh carbon storage resiliency to external disturbances while refining the role salt marshes play in the global carbon cycle.