Modeling Vegetation-Morphology Feedbacks to Inform Delta Restoration Strategies

Understanding the feedback mechanisms between water, sediment, and vegetation in deltaic systems is crucial for advancing ecosystem restoration in the face of accelerating land loss and sea-level rise in coastal zones. Delta morphology is a key driver of ecological resilience, influencing habitat formation and the capacity of ecosystems to withstand climate-related stressors. As sediment diversions become a focal strategy for restoring deltaic landscapes, there is an urgent need to predict how these interventions will shape future deltaic ecosystems. The morphology of a delta directly impacts ecosystem benefits, yet existing models often overlook dynamic vegetation interactions over time, focusing instead on static representations or single-species vegetation in salt marsh settings. This study addresses a major gap by employing numerical simulations with Delft3D Flexible Mesh (DFM) coupled with a dynamic vegetation module in Python, allowing for the simulation of diverse vegetation types and life-history traits as they co-evolve with delta morphology. By modeling vegetation establishment, growth, and mortality under varying flow conditions, we explore vegetation’s role in delta morphology over a decade of morphological evolution. Network-scale metrics describe the delta’s structural evolution, underscoring the significant role of vegetation seasonality and type in shaping delta landscapes. These findings offer essential insights for designing effective ecosystem restoration strategies, such as sediment diversions and marsh creation, particularly relevant to restoration initiatives in coastal Louisiana. Incorporating dynamic vegetation feedback in coastal models can significantly enhance predictions and outcomes for ecosystem restoration in vulnerable deltaic regions.