State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Science and Engineering, Peking University, No.5 Yiheyuan Road Haidian District, Beijing, P.R. China, 10087.
BMC Microbiol. 2020 Aug 1;20(1):235. doi: 10.1186/s12866-020-01913-5.
The Qinghai-Tibetan Plateau represents one of the most important component of the terrestrial ecosystem and a particularly vulnerable region, which harbouring complex and diverse microbiota. The knowledge about their underground microorganisms have largely been studied, but the characteristics of rhizosphere microbiota, particularly archaeal communities remains unclear.
High-throughput Illumina sequencing was used to investigate the rhizosphere archaeal communities of two native alpine trees (Picea crassifolia and Populus szechuanica) living on the Qinghai-Tibetan Plateau. The archaeal community structure in rhizospheres significantly differed from that in bulk soil. Thaumarchaeota was the dominant archaeal phylum in all soils tested (92.46-98.01%), while its relative abundance in rhizospheres were significantly higher than that in bulk soil. Ammonium nitrogen, soil organic matter, available phosphorus and pH were significantly correlated with the archaeal community structure, and the deterministic processes dominated the assembly of archaeal communities across all soils. In addition, the network structures of the archaeal community in the rhizosphere were less complex than they were in the bulk soil, and an unclassified archaeal group (Unclassified_k_norank) was identified as the keystone species in all archaeal networks.
Overall, the structure, assembly and co-occurrence patterns of archaeal communities are significantly affected by the presence of roots of alpine trees living on the Qinghai-Tibetan Plateau. This study provides new insights into our understanding of archaeal communities in vulnerable ecosystems.
青藏高原是陆地生态系统的重要组成部分之一，也是一个特别脆弱的地区，拥有复杂多样的微生物群。虽然人们对其地下微生物有了大量的研究，但对根际微生物群，特别是古菌群落的特征仍不清楚。
本研究采用高通量 Illumina 测序技术，研究了青藏高原两种本地高山树种（云杉和川杨）根际的古菌群落。根际古菌群落的结构与土壤中的结构有明显的不同。泉古菌门是所有测试土壤中的主要古菌门（92.46-98.01%），但其在根际中的相对丰度明显高于土壤中。铵氮、土壤有机质、有效磷和 pH 值与古菌群落结构显著相关，确定性过程主导了所有土壤中古菌群落的组装。此外，根际古菌群落的网络结构比土壤中的结构简单，未分类的古菌群（Unclassified_k_norank）被确定为所有古菌网络中的关键种。
总的来说，根的存在显著影响了青藏高原高山树木的根际古菌群落的结构、组装和共存模式。本研究为我们理解脆弱生态系统中的古菌群落提供了新的见解。
