Project Background

The EPA STAR grant “Effects of Sea Level Rise and Climate Variability on Ecosystem Services of Tidal Marshes, South Atlantic Coast” grew out of existing collaborations between Chris Craft (Wetlands Ecologist), Steve Pennings (Plant Community Ecologist) and Mandy Joye (Biogeochemist), all of whom are Co-PI’s on the Georgia Coastal Ecosystems Long Term Ecological Research study (GCE LTER).  Begun in 2000 and funded through the National Science Foundation, the GCE LTER studies the role of freshwater pulsing on the tidal marsh-estuarine-nearshore complex around Sapelo Island, Georgia.  The GCE LTER experimental design consists of three estuaries (Altamaha River, Doboy Sound, Sapelo Sound) that vary in the delivery of freshwater and sediment.  While tidal wetlands are a component of the GCE LTER study domain, they are just one part of a larger study that spans three estuaries (Altamaha River, Doboy Sound, Sapelo Sound), four ecosystems (terrestrial, wetland, estuary, continental shelf) and 20 plus investigators.

With funding from the EPA STAR program, we are able to expand our wetlands research to additional sites on the Altamaha River and to two other river-dominated estuaries (Ogeechee River, Satilla River) of the Georgia coast.  We also expanded the scale of our research from field-based, ecosystem-level measurements to the landscape scale, relying on the expertise of Jeff Ehman, Landscape Ecologist and GIS expert, formerly at Indiana University.  Jeff’s skills enable us to scale our research findings from site specific locations (e.g. Altamaha River marshes) to the South Atlantic coast of Georgia and South Carolina.   

Jeff recruited noted ecological modeler Dick Park (Eco Modeling) and Jonathan Clough (Warren Pinnacle Consulting) to modify the Sea Level Affects Marshes Model (SLAMM) to apply it to river-dominated estuaries of the Georgia-South Carolina coast.  The model was developed by Dick for EPA in the 1980’s.  The ecosystem-level data, GIS mapping and SLAMM modeling will enable us to predict how wetland area, type (salt-, brackish-, tidal freshwater- marsh) and ecosystem services will respond to different scenarios of sea level rise during the next 100 years or more.  

A second focus of the study is to investigate how climate variability affects the delivery of ecosystem services provided by tidal marshes.  Using six plus years of data from permanent monitoring plots in the GCE LTER study domain, we will investigate how drought, flood, freshwater discharge, salinity and other climate-driven factors affect the delivery of ecosystem services, including marsh accretion, sediment deposition, plant productivity, plant biodiversity and marsh fauna (epibenthic organisms).  

Our EPA STAR project benefits from close collaboration with the GCE-LTER.  GCE-LTER data sets have sparked many of our initial ideas, and, as described above, ongoing GCE-LTER monitoring will continue to provide data that will be critical to the success of this project.