Linking Coastal Adaptation Portfolios to Tidal Marsh Resilience and Sustainable Ecosystem Service Values: Transferable Guidance for Decisions under Uncertainty

  • Johnston, Robert (Primary Chief Investigator (PCI))
  • Kirwan , Matt (Chief Investigator (CI))
  • Leroux, Anke (Chief Investigator (CI))
  • Bauer, Dana Marie (Chief Investigator (CI))

Project: Research

Project Description

Competition and Number: NOAA Climate Program Office FY 2016; NOAA-OAR-CPO-2016-2004413; COCA - Ecosystem Services for a Resilient Coast in a Changing Climate; ID 2542995
Proposal Summary:
Tidal marshes are one of the most common natural and nature-based features (NNBF) used for coastal adaptation, and are frequently promoted for their ability to support coastal resilience and ecosystem services. However, fully functional, permanent marshes cannot simply be built on the coast. Marsh resilience depends on the complex interplay of natural dynamics and human actions. Among the most critical of these actions, the preservation of marsh transgression (or upland migration) zones is often necessary to ensure marsh resilience; the effect of these zones depends on uncertain sea level rise (SLR) and natural dynamics which determine how, when and where marshes migrate. Different types of transgression zones (e.g., different elevations/locations) perform differently depending on uncertain factors such as future SLR. Marshes with different attributes/locations also provide different ecosystem service values. These uncertainties and dynamics imply that diversified portfolios of adaptation actions (e.g., preserving different types of transgression zones in different areas) are best able to ensure the resilience of marsh areas and values. Adaptation decisions rarely capitalize on a systematic understanding of these relationships. The resulting actions face increased risk of failure and underperform in terms of marsh resilience and ecosystem service values, because they fail to diversify sufficiently (they “put too many eggs in one basket”).
The proposed project builds on ongoing collaborative work, existing biophysical/economic datasets, and strong partnerships with local/regional decision-makers to develop tools that address a central coastal adaptation question: Considering the influence of SLR and other uncertain factors on tidal marsh resilience, how can information on biophysical dynamics and economic benefits/costs be coordinated to identify optimal, diversified portfolios of adaptation actions that best sustain marsh resilience and future ecosystem service values? The project first quantifies linkages from adaptation actions to marsh resilience (marsh area and point modeling), to ecosystem service values (structural meta-analyses of ecosystem service values), to optimal diversification (portfolio design). This linked approach will be used to identify the most effective uses of diversified marsh transgression zones to ensure the resilience of marsh area and value. We will develop and illustrate the methods and resulting insights for the Virginia Coast Reserve (VCR) Long Term Ecological Research (LTER) site, in partnership with decision-makers. We will then assess the transferability of results to two other LTER sites, Plum Island Ecosystems, MA (PIE) and Georgia Coastal Ecosystems, GA (GCE). The goal is a systematic, practical and generalizable framework to support diversified adaptation actions that maximize NNBF values. Decision-maker engagement in policy design charrettes will be used to explore management/policy implications.
Short titleCoastal Adaptation Portfolios
AcronymCAP
StatusFinished
Effective start/end date1/08/1631/07/18