Designing wave farms to support mangrove restoration: A coupled hydro-morphodynamic and habitat suitability modelling approach

Wave farms are increasingly proposed for hybrid coastal infrastructure, offering both renewable energy generation and shoreline protection. However, their potential to enable ecological restoration, particularly for mangrove restoration, remains underexplored. This study presents a novel framework for evaluating how wave farms can precondition coastal zones for mangrove restoration by attenuating wave energy, reducing erosion, and expanding areas of hydrodynamic suitability. Using a schematized coupled depth averaged (2DH) hydrodynamic, spectral wave and morphodynamic model in Delft3D, six wave farm configurations were tested under idealized conditions to quantify wave attenuation, sediment retention, and habitat suitability. Mangrove survivability was assessed through a novel drag-based (Type II) erosion- adjusted uprooting threshold. K-means clustering was applied to field-collected morphological traits to define three distinct seedling groups, enabling species-specific resistance modelling based on frontal area and anchorage. The results show that array layout strongly influences ecological and engineering performance. Some configurations enhanced erosion reduction and created more contiguous planting zones while others expanded the total area suitable for restoration. The proposed framework identifies zones preconditioned for restoration, which can be made viable for planting through interventions such as mud nourishment or raised platforms. This study provides a transferable methodology to support hybrid infrastructure design for climate resilience, ecosystem recovery, and local socioeconomic benefit.