Crab is an important benthonic animal in mangrove ecosystem, however, the potential function of crabs on nitrogen (N) transformation in mangrove ecosystems is still poorly understood. The present study aimed to explore the potential effect of crab burrows on nitrification/denitrification within the sediments. The results showed that the presence of crab burrows could directly promote soil nitrification, the regions within more crab burrows appeared to possess higher nitrification. Higher AOA and AOB gene copies were also observed in the sediments surrounding crab burrows than those in the sediments without crab burrow. On the contrary, lower nirS copies, a denitrification related gene, were detected in the sediments surrounding crab burrows. In summary, the present study proposed new evidences of nitrification enhancement deriving by crabs, the presence of crabs might be significant in alleviating nitrification inhibition and benefits the growth of mangroves under tidal flooding.

中文翻译：

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潮间带受蟹影响的红树林沉积物中的氮动态。

螃蟹是红树林生态系统中重要的底栖动物，但是，人们对红树林生态系统中螃蟹对氮（N）转化的潜在功能的了解仍然很少。本研究旨在探讨蟹洞对沉积物中硝化/反硝化作用的潜在影响。结果表明，蟹洞的存在可以直接促进土壤硝化作用，更多的蟹洞区域的硝化作用较高。在蟹穴周围的沉积物中也观察到比没有蟹穴的沉积物中更高的AOA和AOB基因拷贝。相反，在蟹洞周围的沉积物中检测到了较低的nirS拷贝，这是一个与反硝化有关的基因。总而言之，本研究提出了螃蟹促进硝化作用的新证据，