Resilient Coastal Sites for Conservation in the South Atlantic U.S.

Abstract

Sea levels are expected to rise by 1 to 6 feet over the next century, and coastal sites vary markedly in their ability to accommodate such inundation. Sites flanked by extensive lowlands provide space for the coastal habitats within to migrate landward in response to sea-level rise. The amount of space available for habitat migration is determined by the landforms, topography and elevation rise surrounding the tidal zone. However, that potential habitat migration can be strongly influenced by human activities. Even a site that is naturally predisposed to allow for migration may not be able to accommodate sea-level rise if development or disturbances interfere with natural processes. For example, hardened shoreline can create barriers to migration, a lack of sediment can prevent the necessary accumulation of substrate, and an overabundance of nitrogen can disrupt root development, destabilizing the marsh.

In this study, scientists from The Nature Conservancy evaluated more than 1,200 coastal sites in the South Atlantic for their capacity to sustain biodiversity and natural services under increasing inundation from sea-level rise. Each site received a resilience “score” based on the likelihood that its coastal habitats can and will migrate to adjacent lowlands.

The products of this study include:

• A report describing the methods used to evaluate sites and the results for each coastal shoreline region in the South Atlantic
• A web map allowing users to view and interact with the results for any coastal site
• A storymap allowing users to explore a variety of coastal conservation strategies such as land acquisition, restoration, enhancing productivity, prioritizing buy-outs and others
• Downloadable datasets including results for additional sea-level-rise scenarios

To see how the migration space of resilient coastal sites was incorporated into the terrestrial Resilient & Connected Network (RCN), please visit the Resilient Land Mapping Tool.

Citation

Anderson, M.G. and Barnett, A. (2019). Resilient Coastal Sites for Conservation in the South Atlantic US. The Nature Conservancy, Eastern Conservation Science.