Drivers and Impacts of Marsh Migration in the Coastal Critical Zone

Holly Michael

Director, Delaware Environmental Institute
Unidel Fraser Russell Career Development Chair for the Environment
University of Delaware

Tuesday, September 26 at 1:00-2:00 PM PT / 4:00-5:00 PM ET

ABSTRACT

Ghost forests and abandoned farms are stark indicators of ecological change along world coastlines, caused by sea level rise (SLR). These changes adversely affect land use and economies, but conversely expanding coastal marshes resulting from SLR provide crucial ecosystem services such as carbon sequestration and mediate material fluxes to the ocean. Hydrologic shifts are the primary driver of change at the marsh-upland transition. We use linked groundwater-surface water models to understand the critical controls of sea level and upland hydrology on marsh zonation and migration. We show the links between hydrology and biogeochemical conditions, and tie predicted changes to carbon sequestration. This example illustrates the tight coupling between hydrology, ecology, and biogeochemistry in coastal marshes, but many questions remain about drivers and feedbacks in these complex systems with strong hydrologic transience (e.g. tides, storms), tightly coupled ecosystem and biogeochemical mosaics, and human influences that make functioning and response at the marsh-upland transition difficult to understand and predict. We introduce an NSF Critical Zone Network project designed to untangle the hydrological, ecological, geomorphological, and biogeochemical processes that are altering the functioning of the marsh-upland transition in the coastal critical zone, and discuss opportunities for development of coupled models capable of simulating these complex links and feedbacks.

Presentation Slides

Video Link (Coming soon!)