Landscape dynamics in the Southern Atlantic Coastal Plain in response to climate change, sea level rise and urban growth

Background/Question/Methods

Fish and wildlife agencies are increasingly challenged to predict and respond to the potential effects of a changing climate and a changing landscape.  We are working to develop and implement tools for landscape-level strategic habitat conservation (SHC) planning in the South Atlantic Migratory Bird Initiative (SAMBI) region of the Atlantic Coastal Plain. Our work is focused on modeling the impacts of climate change, urban growth, landcover dynamics, and sea-level rise to facilitate projections of future habitat availability for a suite of priority species.

The study area covers the coastal plain from Southern Virginia to Northern Florida and intersects 28 Omernik Level IV ecoregions.  We examined the impacts of climate change via changes in fire frequencies that are tied to temperature, precipitation, evapotranspiration, and soil moisture based on output from twelve Global Climate Models (GCMs) using three CO₂ emission scenarios (A2, A1B, and B1). Urban growth projections were simulated with the SLEUTH-R model and sea level rise was modeled with Sea Level Affecting Marshes Model (SLAMM) with GCM’s under four CO₂ emission scenarios (A2, A1B, B1, and A1FI). We used the Vegetation Dynamics Development Tool (VDDT) simulate the dynamics of the ecological systems and managed forests and the Tool for Exploratory Landscape Scenario Analysis (TELSA) to model those dynamics in a spatial context.  We modeled 78 natural systems and 6 managed systems and generated land cover maps at 10-year intervals from 2001–2100. These land cover maps were used to produce revised vertebrate species distribution maps for the SAMBI region.

Results/Conclusions

Our results show that changes in fire frequency for the different climate projections alter the distribution of age and structure (open vs. closed) classes for the natural land cover.  Urban growth and sea level rise have more localized influences on the habitat availability in the region. The SAMBI region was historically dominated by fire adapted longleaf pine ecosystems. The remaining areas of this ecosystem appear to be resilient to the projected increase in fire frequency. This implies that continued and enhanced longleaf restoration efforts in the region may be one way to continue to provide critical habitat in the face of a changing climate. We will highlight this and other patterns of landscape change throughout the SAMBI.