Estuaries are focal points for coastal cities worldwide, their habitats frequently transformed into engineered shorelines abutting waters with elevated nutrients in an urbanised landscape. Here we test for relationships between shoreline armouring and nutrients on the diversity and trophic composition of fish assemblages across 22 estuaries in eastern Australia. Urbanisation was associated with fish diversity and abundance, but there were differences in the effects of shoreline armouring and nutrient level on the trophic composition of fish assemblages. Fish diversity and the abundance of most trophic groups, particularly omnivores, zoobenthivores and detritivores, was greatest in highly urban estuaries. We show that estuarine fish assemblages are associated with urbanisation in more nuanced ways than simple habitat transformation would suggest, but this depends on the broader environmental context. Our findings have wider implications for estuarine conservation and restoration, emphasizing that ecological benefits of habitat measures may depend on both landscape attributes and water quality in urban settings.

中文翻译：

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景观环境和养分改变了沿海城市化的影响。

河口是全球沿海城市的焦点，它们的栖息地经常被改造成经过工程改造的海岸线，毗邻城市化景观中营养含量较高的水域。在这里，我们测试了澳大利亚东部22个河口的鱼类种群多样性和营养组成对海岸线铠装和养分之间的关​​系。城市化与鱼类的多样性和丰富度有关，但海岸线铠装和营养水平对鱼类组合营养成分的影响存在差异。在高度城市化的河口地区，鱼类的多样性和大多数营养类（尤其是杂食性动物，食虫动物和毁灭性鱼类）的丰度最大。我们表明，与简单的栖息地转换所暗示的相比，河口鱼类组合与城市化的联系更为细致入微，但这取决于更广泛的环境。我们的发现对河口的保护和恢复具有更广泛的意义，强调栖息地措施的生态效益可能取决于城市环境中的景观属性和水质。