MSCI Dissertation Qualifying Exam - Gwen MillerFriday, October 20, 2017 - 1:00pm
Title: Salt marsh health and biomass responses to a changing environment
The South Eastern United States contains a majority of the wetlands within the continental United States, providing this region with protection from hurricanes and storm surges, carbon sequestration, improved water quality, and economic revenue (both by providing aesthetic beauty which attracts tourist and a nursing ground for fisheries). However, climate change will influence the health and survival of these coastal marshes. If sea level rises quicker than a marsh can build elevation the marsh will drown. In addition, the frequency of droughts within the South have increased, which may also have an impact on salt marsh health or survival. To gain a better understanding on how climate change may influence coastal marshes within South Carolina, I propose four projects to increase modelling capabilities, improve our understanding of above and below ground biomass, and how a marsh dieback/decline event after prolonged drought affected a salt marsh. In the first study I will update the Marsh Equilibrium Model (which predicts change in marsh elevations in relation to sea-level rise) to run on large spatial scale and predict elevation change over time within Beaufort and Jasper counties coastal marshes. The second study will assess how the health of a salt marsh responded to a period of drought, and will map regions of vegetation decline and increase. The third study evaluates the use of Planet satellite data to remotely map salt marsh biomass. I will also compare biomass in the areas marked as decline, increase and no change within the second study. This should help highlight if the decline areas are also associated with current day lower biomass. The last study will analyze below ground biomass within salt marshes to better understand how below ground biomass contributes to elevation gains within the marsh. Together these projects will increase our ability to understand how climate change will impact survival of coastal marshes.