不同风化时间碳酸岩表面古菌群落结构与功能特征

【背景】古菌群落是碳酸岩表面微生物群落的重要成员，也是碳酸岩表面生物演替的先锋生物，能够促进碳酸岩风化和加快土壤形成，在生物地球化学循环中起重要作用。【目的】揭示在不同风化时间碳酸岩表面风化残积物中的古菌群落结构及生态功能。方法】采集19-213年风化时间段废弃碳酸岩墓碑表面风化残积物样品(n=18)，基于宏基因组测序技术分析其古菌群落结构与功能特征。【结果】门水平上，优势门有广古菌门(Euryarchaeota)，随后为奇古菌门(Thaumarchaeota)、未鉴定古菌门(unclassified Archaea)、深古菌门(Bathyarchaeota)和泉古菌门(Crenarchaeota)；属水平上，优势属主要由甲烷八叠球菌属(Methanosarcina)、甲烷丝状菌属(Methanothrix)、Methanoperedens、氨氧化古菌属(Nitrosocosmicus)、亚硝化球菌属(Nitrososphaera)及其他未鉴定属组成；C/N、C/P、N/P是显著影响碳酸岩表面古菌群落的主要环境因子。进一步分析发现，碳酸岩表面古菌群落功能丰富，其中新陈代谢(metabo...

Structural and functional characteristics of archaeal community on carbonatite surface weathered for different time

Background] Archaea, the pioneer on the surface of carbonatite, promote the chemical weathering of carbonatite and the formation of soil and play an essential part in biogeochemical process of elements. Objective] To reveal the structure and ecological functions of the archaeal community on the carbonatite surface weathered for different time.Methods] A total of 18 samples were collected from the surface of abandoned carbonatite tombstones (weathered for 19-213 years) in Huaxi District, Guizhou Province, and the structural and functional characteristics of archaeal community were analyzed by metagenomic sequencing. Results] The dominant archaeal phylum was Euryarchaeota, followed by Thaumarchaeota, unclassified Archaea, Bathyarchaeota, and Crenarchaeota. At the genus level, Methanosarcina, Methanothrix, Methanoperedens,Nitrosocosmicus, Nitrososphaera and others unidentified genera were dominant. C/N, C/P and N/P were the main environmental factors that significantly affected the archaeal community on the carbonatite surface. In addition, archaeal community on the surface of carbonatite had diverse functions, particularly metabolism. Euryarchaeota and Thaumarchaeota were the dominant functional groups in the cycling of C, N, and S. The weathering degree of carbonatite significantly increased and the relative abundance of Euryarchaeota and Crenarchaeota obviously decreased over time. Moreover, the relative abundance of Thaumarchaeota had no significant change over time. Conclusion] In summary, we believed that the survival strategy of the archaeal community changed from an r-strategy (Euryarchaeota) to a K-strategy (Thaumarchaeota) with the weathering.