Developing new bio-active surfaces to restore damaged coastal ecosystems

Coastal ecosystems provide essential services such as coastal protection, carbon storage, water purification, and biodiversity support. However, they are experiencing significant decline due to anthropogenic exploitation and climate change. Ecological restoration has emerged as a vital solution to mitigate these losses. Despite notable progress, critical knowledge gaps persist, particularly regarding the effectiveness of various restoration practices, the sustainability of materials used, and the application of innovative concepts that remain underexplored. The severe decline of saltmarshes and the diverse restoration strategies employed to rehabilitate them make these habitats ideal candidates for addressing these gaps and advancing the science and practice of ecological restoration. The overarching aim of this thesis was to evaluate the effectiveness of saltmarsh restoration practices, investigate factors influencing transplant success, and explore innovative strategies to enhance ecological and functional outcomes. The research integrates insights into combining oyster and saltmarsh restoration to improve coastal stability and develops and tests a novel bio-based material for advancing cross-habitat restoration efforts. The results from this thesis highlight the complexities of saltmarsh restoration, emphasising key findings that can guide future efforts. Overall, simpler, single intervention often yield outcomes closer to natural reference conditions than more complex combinatorial approaches, which require careful planning to avoid unintended interactions that may hinder recovery. The lack of standardised metrics to assess restoration success complicates comparisons across projects, underscoring the need for clear and unified evaluation criteria. Long-term monitoring is crucial to capture the full trajectory of recovery, while species-specific strategies are essential for supporting native biodiversity and minimising the spread of invasive species. Balancing the ecological performance and sustainability of the substrata employed is also critical, as some more performative materials pose environmental challenges. Future restoration efforts should explore cross-habitat restoration, such as integrating saltmarsh and oyster reef restoration, to enhance ecosystem connectivity and resilience. Innovative, eco-friendly materials, like bio-based surfaces, offer promising solutions to align restoration with sustainability goals. Together, these findings provide insights and tools to improve saltmarsh restoration practices, fostering coastal resilience and ecosystem sustainability.