MS Thesis Defense: Anna Atencio

The Department of Marine Sciences is proud to present the M.S. Thesis Defense of Anna Atencio. The main location of this event will be in conference room 3204 on the 3rd floor of Murray Hall on UNC campus in Chapel Hill, NC. The defense will be simultaneously streamed live to room 222 at UNC’s Institute of Marine Sciences in Morehead City, NC. This event will be held on Thursday, March 29th at 11:00 AM.

Title: The race to the top. Variations in sediment accumulation rates among salt-marsh and intertidal oyster-reef landscapes.

Abstract: Salt-marsh and oyster reefs, commonly in juxtaposition to each other, are important coastal environments as habitats and coastal protectors. As sea-level rises and marsh and oyster-reef habitats decrease, understanding how these environments function together is necessary for improving restoration and conservation efforts. They have similar mechanisms of sedimentation that rely on internal factors including elevation above sea-level, and marsh grass or oyster density, and external factors including tidal inundation, suspended sediment concentration, and storm frequency. This study quantifies sedimentation rates on oyster reefs and adjacent salt-marshes using ²¹⁰Pb geochronology. Using the constant rate of supply model (Appleby and Oldfield, 1978), we compared the mass accumulation rates for the oyster reef and marsh at each of 4 sites in North Carolina with various oyster reef morphologies. We found that oyster reefs directly attached to marshes will have sediment accumulation rates similar to that of the marsh, regardless of morphology. They are closely coupled and will either thrive or perish together as sea-level rises. Oyster reefs detached from marshes are not as closely coupled and may experience different sediment accumulation rates.