In this paper, an innovative method consisting of the construction of an artificial dune reinforced with a composite made by combining sand and seagrass wrack is presented. The performance of this reinforced dune is compared with sand-only dunes, built at the same time, through data collected during 17 field campaigns (covering a period of one year) carried out with an unmanned aerial vehicle (UAV), whose images allow digital elevation models (DEMs) to be built. The results show that, in the medium term, while the sand-only dunes lose much of their volume (up to 25% of the refilled sediment), the reinforced dune only reduces its volume by around 1.4%. In addition, the cross-shore and longitudinal profiles extracted from the DEMs of the dunes indicate that sand-only dunes greatly reduce the elevation of their crests, while the profile of the reinforced dune remains almost unchanged. This suggests that the addition of seagrass wrack can greatly contribute to increasing the resilience of restored dunes and the time between re-fillings, therefore reducing beach protection costs. However, as the results are based on a single wrack–sand dune and have not been replicated, they should be treated with caution. At the same time, this work illustrates how UAVs can acquire the data needed to map coastal restoration works in a fast and economical way.

Coastal ecosystems are becoming less resilient under climate (e.g., sea-level rise, warming, acidification) and human (e.g., urbanization, coastal hardening, and river regulation) pressures, forcing local communities to face increasing risk levels. This lack of resilience is linked to an adaptation deficit that can be recovered through restoration. Yet, restoration faces barriers related to governance, funding, technical practice, and social context. To overcome such barriers, the REST-COAST project has developed a framework that reckons with coastal restoration platforms and restoration agreements, supported by “enablers” that support the upscaling and implementation of restoration projects. The proposed agreements and platforms can effectively overcome barriers by embedding governance, technical, financial, and social enablers into the agreements among stakeholders. Tailored, place-based approaches foster collaboration, long-term adaptive management, and the scaling of restoration to address accelerating climate-driven risks. The proposed agreements build on hands-on restoration lessons, offering transferable insights for global coastal resilience.

In this paper, an innovative method consisting of the construction of an artificial dune reinforced with a composite made by combining sand and seagrass wrack is presented. The performance of this reinforced dune is compared with sand-only dunes, built at the same time, through data collected during 17 field campaigns (covering a period of one year) carried out with an unmanned aerial vehicle (UAV), whose images allow to build digital elevation models (DEMs). The results show that, on the medium term, while the sand-only dunes lose much of their volume (up to 25% of the refilled sediment), the reinforced dune only reduces its volume by around 1.4%. In addition, the transverse and longitudinal profiles extracted from the DEMs of the dunes indicate that sand-only dunes greatly reduce the elevation of their crests, while the profile of the reinforced dune remains almost unchanged. This suggests that the addition of seagrass wrack can greatly contribute to increase the resilience of restored dunes and the time between re-fillings, reducing, therefore, beach protection costs. At the same time, this work illustrates how UAVs can acquire the data needed to map coastal restoration works in a fast and economical way.

Coastal ecosystems are becoming less resilient under climate (e.g. sea-level rise, warming, acidification) and human (e.g. urbanization, coastal rigidization an driver regulation) pressures, forcing local communities to face increasing risk level. This lack of resilience is linked to an adaptation deficit that can be recovered through restoration. Yet, restoration faces barriers related to governance, funding, technical practice, and social context. To overcome such barriers the REST-COAST project has developed a framework that reckons with coastal restoration platforms and restoration contracts, supported by “enablers” that support the upscaling and implementation of restoration projects. The proposed contracts and platforms can effectively overcome barriers by embedding governance, technical, financial, and social enablers into the agreements among stakeholders. Tailored, place-based approaches foster collaboration, long-term adaptive management, and scaling of restoration to address accelerating climate driven risks. The obtained hands-on restoration lessons offer transferable insights for global coastal resilience.