Wetlands Accretion

Wetland Accretion and Sediment Supply

The image caption follows
Prof. Craft's students in field setting up research equipment

Coastal wetlands provide important ecosystem services, such as protection from flood and storm damage, providing a nursery for commercially important finfish and shellfish, and sequestering carbon. Recent research has shown that river sediment inputs are important for the long-term stability of coastal wetlands, such as Spartina alterniflora-dominated salt marshes. These sediment inputs are expected to become even more important as sea level rise threatens to flood coastal wetland areas. However, the damming of rivers and changes in land use have led to a decline in sediment inputs to coastal areas over the past few decades, and this decline is expected to have a negative effect on coastal wetlands.

We measure annual accretion rates, soil carbon and nitrogen content, above- and belowground biomass, and elevation of Spartina alterniflora salt marsh at the mouths of three rivers in the Southeastern U.S.: the Cape Fear (NC), Edisto (SC), and Altamaha (GA) Rivers. Results from these studies will inform our knowledge of how susceptible coastal wetlands (in particular, salt marshes) are to sea level rise and how the effects can be mitigated by sediment management on the land. Our work is supported by NSF through a region-wide (east coast) grant to researchers at Villanova University, University of South Carolina, Virginia Commonwealth University, and Indiana University.