Marine coastal ecosystems are crucial to human populations in reducing disaster risk. Least Developed Countries are particularly vulnerable to the effects of climate change, such as sea‐level rise and storm surges. The Mauritanian coast, West Africa, ranks among the most vulnerable worldwide to sea‐level rise, and coastal communities in the National Park of Banc d’Arguin (PNBA) are particularly at risk. Here, we assessed the service of coastal protection in PNBA by (1) mapping the coastal marine ecosystems with Sentinel‐2 imagery and determining their spatial wave height attenuation rates; (2) assessing the vulnerability of villages and natural habitats to coastal hazard risk; and (3) assessing the applicability of coastal protection measures in the PNBA. We found that a total of 83% of the populated coastline presents a moderate to high risk of flooding and erosion, with Iwik and R’Gueiba being the most threatened villages in the PNBA. As for the ecological risk, two low‐elevated islands, which support breeding colonies of birds, are particularly vulnerable to sea‐level rise. However, in other areas, the rupture in the dune cord created new lagoons that present valuable ecological and economic interests like the Lagoon of Bellaat. Improving the comprehension of wave attenuation provided by coastal habitats, combined with identifying the vulnerability and applicability of coastal protection measures, is essential for achieving the Sendai Framework for Disaster Risk Reduction goals. In the PNBA, relocation of identified villages at risk is probably the best cost‐effective solution with the least disturbance to both breeding and wintering birds. Protection of coastal ecosystems will also ensure a continued provision of other ecosystem services, including food supply for sea dependent populations, and contribute to achieving the Paris Agreement and Sustainable Development Goals.

中文翻译：

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海岸保护评估：生态，社会和经济问题之间的权衡

海洋沿海生态系统对于减少灾害风险对人类至关重要。最不发达国家特别容易受到气候变化的影响，例如海平面上升和风暴潮。西非的毛里塔尼亚海岸是全世界最容易受到海平面上升影响的地区之一，阿尔班国家公园（PNBA）的沿海社区尤其受到威胁。在这里，我们通过（1）用Sentinel-2影像绘制沿海海洋生态系统的地图并确定其空间波高衰减率来评估PNBA中的海岸保护服务；（2）评估村庄和自然栖息地对沿海灾害风险的脆弱性；（3）评估PNBA中沿海保护措施的适用性。我们发现，总共83％的人口稠密海岸线存在中度到高度的洪泛和侵蚀风险，其中Iwik和R'Gueiba是PNBA中受威胁最大的村庄。至于生态风险，两个低海拔的岛屿特别容易受到海平面上升的影响，这两个岛屿支持鸟类的繁殖地。但是，在其他地区，沙丘绳索的破裂产生了新的泻湖，这些泻湖展现了宝贵的生态和经济利益，例如贝拉特泻湖。改善沿海生境提供的波衰减的认识，并确定沿海保护措施的脆弱性和适用性，对于实现《仙台减少灾害风险框架》目标至关重要。在PNBA中 搬迁已确定的有风险的村庄可能是成本效益最好的解决方案，对繁殖和越冬鸟类的干扰最小。保护沿海生态系统还将确保继续提供其他生态系统服务，包括向依赖海洋的人口提供食物，并有助于实现《巴黎协定》和可持续发展目标。