Saltmarsh, a prominent buffer ecosystem, has been identified as an important sink for nitrogen (N) pollutants from marine- and land-based anthropogenic activities. However, how the enriched anthropogenic N impacts saltmarsh sustainability has been neglected due to limited understanding of marsh resilience based on seedling establishment and population dispersal under anthropogenic N inputs. This study combined mesocosm experiments and model simulations to quantify the effects of increased anthropogenic N on the seedling-based vegetation expansion of . The results indicated that seedling survivals, growth rates, and morphological indicators were inhibited by 20.08 %, 37.14 %, and > 35.56 %, respectively, under 1.5 gN/kg anthropogenic N. The sensitivity rate of vegetation expansion was increased by 70 % with 1 gN/kg increased N concentration under the scenario of low seedling density (< 15 m/yr). These findings revealed an important unidentified weakness of the marsh development process to anthropogenic N inputs. Finally, we highlighted the importance of appropriate protection measures to control nutrient pollution in salt marshes. Our study provides new insights for enhancing the resilience and sustainability of saltmarsh ecosystems.

中文翻译：

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人为氮污染影响盐沼恢复力，抑制幼苗生长和种群扩散

盐沼是一个重要的缓冲生态系统，已被确定为海洋和陆地人类活动中氮（N）污染物的重要汇。然而，由于对基于人为氮输入下的幼苗建立和种群扩散的沼泽恢复力的了解有限，丰富的人为氮如何影响盐沼的可持续性一直被忽视。本研究结合中生态实验和模型模拟来量化人为氮增加对幼苗植被扩张的影响。结果表明，在1.5 gN/kg的人为施氮条件下，幼苗成活率、生长率和形态指标分别受到20.08%、37.14%和>35.56%的抑制，植被扩张敏感率提高70%，1 gN/kg 在低苗密度（< 15 m/yr）的情况下增加了氮浓度。这些发现揭示了沼泽发展过程对人为氮输入的一个重要的、未识别的弱点。最后，我们强调了采取适当的保护措施来控制盐沼营养物污染的重要性。我们的研究为增强盐沼生态系统的恢复力和可持续性提供了新的见解。