Coastal hazards such as flooding and land loss has demanded natural and nature-based solutions from local communities for their protective services as well as co-benefits compared to typical engineered approaches. Natural solutions are those that consider conserving existing habitats such as salt marshes and the nature-based solutions are those created by humans, such as created marshes. These solutions support important ecosystem processes, such as wave attenuation, nutrient assimilation, primary production in nursery habitats for fisheries, and carbon storage. Quantifying these ecosystem processes and their related ecosystem services overtime with management actions has been limited but needed to assess how natural and nature-based solutions are impacting local communities.
Our goal was to co-develop a natural and nature-based defense assessment and solutions tool with local communities. The tool will help capture feedback of the ecological and physical characteristics of ecosystem via an ecosystem model, encompass the needs and knowledge of local communities, and will be applicable and transferable to other ecosystems. Our main research questions are: What is the contribution of natural and nature-based solutions to wave attenuation, fish habitat, nutrient assimilation, and carbon storage? Can collaborative approaches to modeling with communities potentially produce innovative solutions or tools for reducing coastal risk?
Results/Conclusions
A Competency Group was created that includes engineers, social and natural scientists, and local community members that interact frequently (at least five meetings scheduled over a 12-month period) to discuss existing and proposed natural and nature-based defenses in Breton Sound Estuary, coastal Louisiana. The Competency Group meetings are organized and facilitated by social scientists where the ecosystem modeling and analysis is led by engineers and ecologists. An Integrated Biophysical Model (Delft3D flexible mesh) that represents the local hydrodynamics, morphodynamics, nutrient dynamics and vegetation dynamics was adjusted for this estuary and input from the local community about the preferred natural and nature-based defenses was applied. Scenarios that included extreme conditions such as hurricane-force winds and water levels and drought conditions were considered by the Competency Group and run with the ecosystem model to include areas with and without natural or nature-based solutions. The results from the scenarios consider how these solutions influence wave attenuation, nutrient assimilation, primary production in nursery habitats for fisheries, and carbon storage. This project suggests a novel approach to modeling ecosystem-based defense strategies through a collaborative planning process with researchers and local communities who stand to benefit from ecosystem-based restoration projects.