College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China.
College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.
Sci Rep. 2019 Dec 18;9(1):19326. doi: 10.1038/s41598-019-55940-y.
The spatial variability of microorganisms in grasslands can provide important insights regarding the biogeographic patterns of microbial communities. However, information regarding the degree of overlap and partitions of microbial communities across different habitats in grasslands is limited. This study investigated the microbial communities in three distinct habitats from Xilingol steppe grassland, i.e. animal excrement, phyllosphere, and soil samples, by Illumina MiSeq sequencing. All microbial community structures, i.e. for bacteria, archaea, and fungi, were significantly distinguished according to habitat. A high number of unique microorganisms but few coexisting microorganisms were detected, suggesting that the structure of microbial communities was mainly regulated by species selection and niche differentiation. However, the sequences of those limited coexisting microorganisms among the three different habitats accounted for over 60% of the total sequences, indicating their ability to adapt to variable environments. In addition, the biotic interactions among microorganisms based on a co-occurrence network analysis highlighted the importance of Microvirga, Blastococcus, RB41, Nitrospira, and four norank members of bacteria in connecting the different microbiomes. Collectively, the microbial communities in the Xilingol steppe grassland presented strong habitat preferences with a certain degree of dispersal and colonization potential to new habitats along the animal excrement- phyllosphere-soil gradient. This study provides the first detailed comparison of microbial communities in different habitats in a single grassland, and offers new insights into the biogeographic patterns of the microbial assemblages in grasslands.
草原微生物的空间变异性可以为微生物群落的生物地理模式提供重要的见解。然而，关于草原不同生境中微生物群落的重叠和分区程度的信息有限。本研究通过 Illumina MiSeq 测序，调查了锡林郭勒草原三个不同生境（动物粪便、叶际和土壤样本）中的微生物群落。根据生境，所有微生物群落结构（细菌、古菌和真菌）均显著不同。检测到大量独特的微生物，但共存的微生物较少，这表明微生物群落的结构主要受到物种选择和生态位分化的调节。然而，在这三个不同生境中，那些有限的共存微生物的序列占总序列的 60%以上，表明它们具有适应多变环境的能力。此外，基于共现网络分析的微生物间生物相互作用强调了 Microvirga、Blastococcus、RB41、Nitrospira 和细菌的四个未分类成员在连接不同微生物组方面的重要性。总的来说，锡林郭勒草原的微生物群落表现出强烈的生境偏好，具有一定的扩散和定植潜力，可沿着动物粪便-叶际-土壤梯度向新的生境扩散。本研究首次对单个草原中不同生境的微生物群落进行了详细比较，为草原微生物组合的生物地理模式提供了新的见解。
