Abstract As a famous plateau lake and a place rich in biodiversity located at the Hengduan Mountains, there is little research on microbial diversity and community composition in Erhai. In this study, 770,425 16S rRNA sequences had obtained at different depth samples. The abundance‐based coverage estimates (ACE), Chao1, and Shannon indices indicated the high abundance and diversity of Erhai sediment microorganisms. And they were obviously affected by human disturbance. Gammaproteobacteria, Deltaproteobacteria, Bacteroidia, Anaerolineae, Phycisphaerae, and Methanomicrobia were dominant bacteria and existed in almost all samples. The content of total nitrogen (TN) in sediments had a significant positive correlation between Syntrophus, Deltaproteobacteria, Desulfatiglans, Oxyphotobacteria, Clostridiales, Burkholderiaceae, Geobacter, Crenothrix species richness. Desulfobacca, Syntrophus, Deltaproteobacteria, Desulfatiglans, Gammaproteobacteria, Oxyphotobacteria, and Clostridiales were positively correlated with the nitrates in sediments. And the species richness of Desulfatiglans was correlated with NO2 -. The RDA analysis was shown that dbRDA1 was affected mainly by the depth of lake, while the content of TN, NO3 −, NO2 −, and NH4 + had the largest effect on dbRDA2. The results indicated the great relations between the diversity and composition of microbial communities and different forms of sediment nitrogen in Erhai lake sediments.

中文翻译：

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滇桂高原洱海沉积物中氮和微生物群落的分化

摘要 作为著名的高原湖泊和位于横断山脉的生物多样性丰富的地方，洱海对微生物多样性和群落组成的研究较少。在本研究中，在不同深度的样本中获得了 770,425 个 16S rRNA 序列。基于丰度的覆盖估计（ACE）、Chao1 和 Shannon 指数表明洱海沉积物微生物的丰度和多样性。而他们显然受到了人为干扰的影响。Gammaproteobacteria、Deltaproteobacteria、Bacteroidia、Anaerolineae、Phycisphaerae 和 Methanomicrobia 是优势菌，几乎存在于所有样品中。沉积物中总氮(TN)含量与Syntrophus、Deltaproteobacteria、Desulfatiglans、Oxyphotobacteria、Clostridiales、Burkholderiaceae、Geobacteria、Crenotrix 物种丰富度。Desulfobacca、Syntrophus、Deltaproteobacteria、Desulfatiglans、Gammaproteobacteria、Oxyphotobacteria 和Clostridiales 与沉积物中的硝酸盐呈正相关。Desulfatiglans的物种丰富度与NO2-相关。RDA分析表明，dbRDA1主要受湖水深度的影响，而TN、NO3-、NO2-和NH4+的含量对dbRDA2的影响最大。结果表明，洱海沉积物中微生物群落的多样性和组成与沉积物氮的不同形式之间存在很大关系。Desulfatiglans的物种丰富度与NO2-相关。RDA分析表明，dbRDA1主要受湖水深度的影响，而TN、NO3-、NO2-和NH4+的含量对dbRDA2的影响最大。结果表明，洱海沉积物中微生物群落的多样性和组成与沉积物氮的不同形式之间存在很大关系。Desulfatiglans的物种丰富度与NO2-相关。RDA分析表明，dbRDA1主要受湖水深度的影响，而TN、NO3-、NO2-和NH4+的含量对dbRDA2的影响最大。结果表明，洱海沉积物中微生物群落的多样性和组成与沉积物氮的不同形式之间存在很大关系。