Wu Ming-Hui, Li Ting, Zhang Gao-Sen, Wu Fa-Si, Chen Tuo, Zhang Bing-Lin, Wu Xiu-Kun, Liu Guang-Xiu, Zhang Ke-Cun, Zhang Wei
Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Key Laboratory of Desert and Desertification, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, Gansu, China.
State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, Gansu, China.
Microb Ecol. 2023 May;85(4):1382-1395. doi: 10.1007/s00248-022-02043-3. Epub 2022 May 18.
Understanding how microbial communities adapt to environmental stresses is critical for interpreting ecological patterns and microbial diversity. In the case of the Gobi Desert, little is known on the environmental factors that explain hypolithic colonization under quartz stones. By analyzing nine hypolithic communities across an arid gradient and the effects of the season of the year in the Hexi Corridor of this desert, we found a significant decrease in hypolithic colonization rates (from 47.24 to 15.73%) with the increasing drought gradient and found two distinct communities in Hot and Cold samples, which survived or proliferated after a hot or a cold period. While Cold communities showed a greater species diversity and a predominance of Cyanobacteria, Hot communities showed a predominance of members of the Proteobacteria and the Firmicutes. In comparison, Cold communities also possessed stronger functions in the photosynthesis and carbon metabolism. Based on the findings of this study, we proposed that the hypolithic communities of the Hexi Corridor of the Gobi Desert might follow a seasonal developmental cycle in which temperature play an important role. Thus after a critical thermal threshold is crossed, heterotrophic microorganisms predominate in the hot period, while Cyanobacteria predominate in the cold period.
了解微生物群落如何适应环境压力对于解释生态模式和微生物多样性至关重要。就戈壁沙漠而言，对于解释石英石下石下微生物群落定殖的环境因素知之甚少。通过分析沿干旱梯度的九个石下微生物群落以及该沙漠河西走廊一年中不同季节的影响，我们发现随着干旱梯度的增加，石下微生物群落定殖率显著下降（从47.24%降至15.73%），并且在高温和低温样本中发现了两个不同的群落，它们在高温或低温期后存活或增殖。低温群落表现出更高的物种多样性，且以蓝细菌为主，而高温群落则以变形菌门和厚壁菌门成员为主。相比之下，低温群落在光合作用和碳代谢方面也具有更强的功能。基于本研究的结果，我们提出戈壁沙漠河西走廊的石下微生物群落可能遵循一个季节性发育周期，其中温度起着重要作用。因此，在越过临界热阈值后，异养微生物在高温期占主导地位，而蓝细菌在低温期占主导地位。
