Zhang Wei, Bahadur Ali, Sajjad Wasim, Zhang Gaosen, Nasir Fahad, Zhang Binglin, Wu Xiukun, Liu Guangxiu, Chen Tuo
Key Laboratory of Desert and Desertification, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China.
Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Lanzhou 730000, China.
Microorganisms. 2021 Jan 27;9(2):262. doi: 10.3390/microorganisms9020262.
Bacterial communities in cold-desert habitats play an important ecological role. However, the variation in bacterial diversity and community composition of the cold-desert ecosystem in Qinghai-Tibet Plateau remains unknown. To fill this scientific gape, Illumina MiSeq sequencing was performed on 15 soil samples collected from different cold-desert habitats, including human-disturbed, vegetation coverage, desert land, and sand dune. The abundance-based coverage estimator, Shannon, and Chao indices showed that the bacterial diversity and abundance of the cold-desert were high. A significant variation reported in the bacterial diversity and community composition across the study area. Proteobacteria accounted for the largest proportion (12.4-55.7%) of all sequences, followed by Actinobacteria (9.2-39.7%), Bacteroidetes (1.8-21.5%), and Chloroflexi (2.7-12.6%). Furthermore, unclassified genera dominated in human-disturbed habitats. The community profiles of GeErMu, HongLiangHe, and CuoNaHu sites were different and metagenomic biomarkers were higher (22) in CuoNaHu sites. Among the soil physicochemical variables, the total nitrogen and electric conductivity significantly influenced the bacterial community structure. In conclusion, this study provides information regarding variation in diversity and composition of bacterial communities and elucidates the association between bacterial community structures and soil physicochemical variables in cold-desert habitats of Qinghai-Tibet Plateau.
寒冷沙漠栖息地中的细菌群落发挥着重要的生态作用。然而，青藏高原寒冷沙漠生态系统中细菌多样性和群落组成的变化仍不为人知。为填补这一科学空白，对从不同寒冷沙漠栖息地采集的1５份土壤样本进行了Illumina MiSeq测序，这些栖息地包括人为干扰区、植被覆盖区、沙漠地和沙丘。基于丰度的覆盖率估计值、香农指数和 Chao 指数表明，寒冷沙漠中的细菌多样性和丰度较高。研究区域内细菌多样性和群落组成存在显著差异。变形菌门在所有序列中占比最大（12.4-55.7%），其次是放线菌门（9.2-39.7%）、拟杆菌门（1.8-21.5%）和绿弯菌门（2.7-12.6%）。此外，未分类的属在人为干扰栖息地中占主导地位。格尔木、红梁河和错那湖站点的群落概况不同，错那湖站点的宏基因组生物标志物更多（22个）。在土壤理化变量中，总氮和电导率显著影响细菌群落结构。总之，本研究提供了有关细菌群落多样性和组成变化的信息，并阐明了青藏高原寒冷沙漠栖息地中细菌群落结构与土壤理化变量之间的关联。
