Who You Gonna Call?
Powell in the transitional ecotone between the upland and marsh.
In Delaware, sea levels have risen more than a foot in the past 100 years, and according to Delaware’s sea level rise projections, the state could see another 1.5 feet increase by 2050. One impact of this change can be seen at the interface of “ghost forests”—dying woodlands where salty water is slowly poisoning living trees—and the migration of marshes in search of higher ground.
Where will the marshes go? What will happen to the forests? These are questions that intrigued Lizzy Powell, Margaret A. Davidson Fellow at the Delaware Reserve, PhD candidate at the University of Maryland, and resident “Ghost Buster” for the Reserve.
“Rising sea levels can transform tidal wetland into mudflats or open water,” says Powell. “Marshes, however, can cope with accelerated sea-level rise by migrating into nearby forests. Communities need to understand this change so they can plan adaptation strategies to protect these resources for the future.”
Powell is exploring the initial effects of marsh migration on coastal forests by using light detection and ranging technology (LiDAR). LiDAR is typically used in forestry and on land. With this technology, she is able to track initial landscape-level changes by measuring the vertical structure of forests in areas of increased inundation.
“Determining how tidal marshes are dealing with sea level rise is critical for policy-makers,” says Powell. “I think the use of LiDAR technology could tackle some of those questions!”
Lizzy is at work on her PhD., which highlights the relevance of using LiDAR in studying forest dieback in Delaware Bay. LiDAR can also help predict future marsh migration routes, so decision makers understand which areas are vulnerable to increased flooding and plan accordingly.