长江口潮滩沉积物古菌群落结构与多样性

以长江口潮滩为研究对象，采用高通量测序技术，研究了潮滩沉积物古菌群落结构与多样性及其影响因素.结果表明，沉积物中古菌群落OTUs数量为900~1417，Shannon指数为7.02~8.02，均表现出从低盐度向高盐度样点降低的变化特征.各采样点古菌群落特异性OTUs占各采样点总OTUs的24.2%~57.3%，而共有的OTUs仅占1.2%，说明各样点沉积物中古菌群落特异性较高.沉积物中古菌主要隶属于广古菌门（Euryarchaeota）和奇古菌门（Thaumarchaeota），而深古菌门（Bathyarchaeota）也是古菌群落的重要组成部分，其相对丰度占到17.7%~25.9%.主成分和聚类分析表明芦潮港和东海农场沉积物中古菌群落结构相似，白龙港和浏河口群落组成相近，而浒浦与其他采样点的古菌群落组成差别较大.通过典范对应分析，研究区沉积物中古菌群落结构与沉积物盐度水平有着非常密切的关系.上述研究结果表明长江口潮滩沉积物中古菌群落结构组成和多样性具有高度的空间差异性，且沉积物盐度是群落差异的决定性影响因素.

Archaeal community structure and diversity in intertidal sediments of the Yangtze River Estuary

High-throughput sequencing was used to investigate the archaeal community structure and diversity, and associated influencing factors in the intertidal sediments of the Yangtze Estuary. The results indicated that the OTUs and Shannon index of archaeal community in the intertidal sediments were 900~1417 and 7.02~8.02, respectively, which both decreased from low to high salinity sampling sites. The specific OTUs of archaeal community structure accounted for 24.2%~57.3% of total OTUs in each sampling site, and identical OTUs only occupied for 1.2%, indicating that archaeal community structure varied highly along the sampling sites. The archaeal community was dominated by the Euryarchaeota and Thaumarchaeota. The Bathyarchaeota contributed a great parts of archaeal community, accounting for 17.7%~25.9% of total community. The principal component and cluster analysis suggested that the archaeal community structure in sites LCG and DHNC was similar, and archaeal community structure in BLG showed a similarity with LHK, while archaeal community structure showed a great difference in XP compared to others sampling sites. Canonical correlation analysis suggested that distribution of archaeal community structure in the intertidal sediments was tightly correlated with the sediment salinity. These results indicated that archaeal community structure and diversity were highly variable in the intertidal sediments of the Yangtze Estuary. In addition, sediment salinity was the crucial factor affecting the variabilities in archaeal community structure and diversity in the Yangtze Estuary.