Coastal areas offer a diversity of habitats providing refugia and nursery for fish, promoting their biodiversity and associated contributions to people. Yet, natural coastlines are replaced by artificial infrastructures such as seaports and the influence of this artificialization on fish biodiversity remains poorly known. Here, we assessed fish biodiversity indicators using environmental DNA metabarcoding inside seaports and adjacent natural habitats including no-take marine reserves. We found that species assemblages within seaports were primarily influenced by their area and habitat. We detected a similar species richness in seaports and reserves during lockdown, but seaports host more threatened species than natural habitats. Yet, species turnover between seaports was lower than between natural areas, reflecting biotic homogenization. Seaport managers should consider that complexifying artificial infrastructures could increase habitat diversity and coastal fish biodiversity. Our study illustrates that eDNA-based indicators can be integrated in management and policy applications toward greener marine artificial infrastructures.

中文翻译：

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利用 eDNA 和附近海洋保护区对海港鱼类生物多样性进行基准测试

沿海地区提供多样化的栖息地，为鱼类提供庇护所和苗圃，促进其生物多样性以及对人类的相关贡献。然而，自然海岸线被海港等人工基础设施所取代，而这种人工化对鱼类生物多样性的影响仍然鲜为人知。在这里，我们使用海港和邻近自然栖息地（包括禁捕海洋保护区）内的环境 DNA 元条形码评估了鱼类生物多样性指标。我们发现海港内的物种组合主要受其面积和栖息地的影响。我们在封锁期间在海港和保护区发现了类似的物种丰富度，但海港的受威胁物种比自然栖息地更多。然而，海港之间的物种更替低于自然区域之间的物种更替，反映出生物同质化。海港管理者应考虑到复杂的人工基础设施可以增加栖息地多样性和沿海鱼类生物多样性。我们的研究表明，基于 eDNA 的指标可以整合到管理和政策应用中，以实现更绿色的海洋人工基础设施。