Abstract River deltas and estuaries are disproportionally-significant coastal landforms that are inhabited by nearly 600 M people globally. In recent history, rapid socio-economic development has dramatically changed many of the World's mega deltas, which have typically undergone agricultural intensification and expansion, land-use change, urbanization, water resources engineering and exploitation of natural resources. As a result, mega deltas have evolved into complex and potentially vulnerable socio-ecological systems with unique threats and coping capabilities. The goal of this research was to establish a holistic understanding of threats, resilience, and adaptation for four mega deltas of variable geography and levels of socio-economic development, namely the Mekong, Yellow River, Yangtze, and Rhine deltas. Compiling this kind of information is critical for managing and developing these complex coastal areas sustainably but is typically hindered by a lack of consistent quantitative data across the ecological, social and economic sectors. To overcome this limitation, we adopted a qualitative approach, where delta characteristics across all sectors were assessed through systematic expert surveys. This approach enabled us to generate a comparative assessment of threats, resilience, and resilience-strengthening adaptation across the four deltas. Our assessment provides novel insights into the various components that dominate the overall risk situation in each delta and, for the first time, illustrates how each of these components differ across the four mega deltas. As such, our findings can guide a more detailed, sector specific, risk assessment or assist in better targeting the implementation of risk mitigation and adaptation strategies.

中文翻译：

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大型三角洲的复原力和适应能力分析：湄公河、黄河、长江和莱茵河三角洲的比较评估

摘要 河流三角洲和河口是不成比例的重要沿海地貌，全球有近 6 亿人居住。在近代历史上，快速的社会经济发展极大地改变了世界上许多大型三角洲，这些三角洲通常经历了农业集约化和扩张、土地利用变化、城市化、水资源工程和自然资源开发。因此，巨型三角洲已经演变成复杂且潜在脆弱的社会生态系统，具有独特的威胁和应对能力。本研究的目标是全面了解四个地理和社会经济发展水平各不相同的巨型三角洲，即湄公河、黄河、长江和莱茵河三角洲的威胁、复原力和适应能力。编制此类信息对于可持续地管理和开发这些复杂的沿海地区至关重要，但通常会受到生态、社会和经济部门缺乏一致的定量数据的阻碍。为了克服这一限制，我们采用了定性方法，通过系统的专家调查评估了所有部门的三角洲特征。这种方法使我们能够对四个三角洲的威胁、弹性和增强弹性的适应进行比较评估。我们的评估提供了对主导每个三角洲整体风险状况的各种组成部分的新颖见解，并首次说明了这些组成部分中的每一个在四个大型三角洲之间有何不同。因此，我们的发现可以指导更详细的、针对特定部门的、