NSF Project Title: COLLABORATIVE RESEARCH: RUI: THE INFLUENCE OF MANGROVE INVASION AND RISING TEMPERATURES ON BELOWGROUND PROCESSES IN COASTAL ECOSYSTEMS

Along the Florida coastline, mangroves are rapidly encroaching northward into territory previously inhabited by temperate salt marsh ecosystems due to reduced freeze events. Wetland vegetation type largely dictates ecosystem function and ecosystem services, so it is predicted that dramatic changes in dominant vegetation cover could significantly alter ecosystem processes within coastal tidal wetlands. However, it is currently unknown how these dramatic shifts in dominant coastal vegetation will impact “on the ground” processes within these ecosystems, such as decomposition, carbon sequestration, and root growth.

In order to better understand how coastal wetlands at this intersection of tropical and temperate environments will survive under rising sea levels, I plan to investigate belowground root and soil processes both at Florida field sites and within experimental mesocosms housed in the Villanova University greenhouse. At the field sites, I will collect soil cores to measure root biomass at different depths, install root ingrowth bags to measure root growth rates, install decomposition ladders to measure decomposition rates at different depths, and deploy redox probes to measure soil oxygen concentrations. Using greenhouse mesocosms containing combinations of soil type (C3 or C4) and vegetation (Avicennia germinans or Spartina alterniflora) type, I will calculate how soil and vegetation type impacts soil respiration rates. I will work under the supervision of my mentor, Dr. Samantha Chapman, and my committee members, Dr. Adam Langley and Dr. Kelman Wieder.

Publications:

Geoghegan, E.G., Langley, J.A., Chapman S.K. 2020. A comparison of mangrove and marsh influences on soil respiration rates: A mesocosm study. Estuarine, Coastal and Shelf Science. https://doi.org/10.1016/j.ecss.2020.106877.

Check out more info on the GTM Research Reserve website: https://www.gtmnerr.org/research/emergent-vegetation/