According to a 2007 report by the Intergovernmental Panel on Climate Control, global sea level is expected to increase one half meter or more over the next century. Along the Mid-Atlantic coast of the United States, relative sea-level rise is about two times higher than the global rise.
In Delaware, nearly 371,000 acres of contiguous tidal wetlands surround the Delaware Bay. Studies indicate that the proportion of wetlands that were degraded increased from 25 percent in 1984 to an alarming 54 percent in 1993.
Three University of Delaware scientists are studying tidal water flow and sediment movement in a Kent County salt marsh to better understand changes to the marsh ecosystem due to a rising sea level.
Brockonbridge Marsh is a tidal wetland adjacent to Brockonbridge Gut, a small tidal creek located approximately 24 miles upstream from the mouth of the Delaware Bay. It is characterized by daily tidal flooding and extensive cordgrass vegetation.
Increasing rates of sea level rise could convert this tidal wetland to an intertidal flat, an environment where muddy sediment can be quickly eroded. This conversion to an intertidal flat has the potential to alter water quality by releasing large quantities of sequestered carbon, nutrients and pollutants, and could affect wildlife such as birds, crabs and fish that live in coastal marshes and waters.
“Developing new methods to quantify water and sediment movement in these wetlands, on marsh surfaces and in small tidal channels will provide critical information related to marsh stability. This information is needed to predict future changes,” said Jack Puleo, associate professor of civil and environmental engineering and in the Center for Applied Coastal Research.
Puleo is co