Wang Zhujun, Feng Kai, Lu Guangxin, Yu Hao, Wang Shang, Wei Ziyan, Dang Ning, Wang Yingcheng, Deng Ye
CAS Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China.
Front Microbiol. 2022 Feb 24;13:801083. doi: 10.3389/fmicb.2022.801083. eCollection 2022.
Global warming is likely to affect the underground microbial communities in various ecosystems, but the response of soil microbial communities along a vertical depth profile to global warming has been elusive. Herein, we leveraged a warming field experiment in Qinghai-Tibet Plateau grassland and investigated the community structure of prokaryotes and fungi from the upper (0-15 cm) and lower (15-30 cm) strata under ambient and elevated temperature treatments. Three-years continual warming only significantly shifted the prokaryotic community within the upper strata and there was no significant effect observed for the fungal community. Additionally, under ambient temperature, there were significant differences between the two strata in both the prokaryotic and fungal communities, but under warming, this effect was alleviated. Next, the prokaryotic and fungal community assembly processes were measured by a phylogenetic-bin-based null approach (iCAMP). Though deterministic and stochastic processes dominated the assembly of prokaryotic and fungal communities, respectively, the deterministic processes were strengthened under warming for both communities. Specifically, the increased portion of homogeneous selection, contributing to a homogenous state, led to a smaller difference between prokaryotic communities of the two soil strata under warming. The smaller difference in the stochastic process component, , dispersal limitation, contributed to the similar fungal community structures between the two strata under warming. This study deepens our understanding of warming effects on grassland microbial communities and gives greater insights on the underlying mechanisms for microbial assembly between upper and lower soil strata under warming scenarios.
全球变暖可能会影响各种生态系统中的地下微生物群落，但土壤微生物群落在垂直深度剖面上对全球变暖的响应一直难以捉摸。在此，我们利用青藏高原草原的增温田间试验，研究了在环境温度和升高温度处理下，上层（0-15厘米）和下层（15-30厘米）地层中原核生物和真菌的群落结构。连续三年的增温仅显著改变了上层地层中的原核生物群落，而对真菌群落未观察到显著影响。此外，在环境温度下，原核生物和真菌群落的两个地层之间存在显著差异，但在增温条件下，这种影响得到缓解。接下来，通过基于系统发育箱的零模型方法（iCAMP）测量原核生物和真菌群落的组装过程。尽管确定性过程和随机过程分别主导了原核生物和真菌群落的组装，但在增温条件下，两个群落的确定性过程均得到加强。具体而言，同质化选择增加的部分导致了同质化状态，使得增温条件下两个土壤地层的原核生物群落之间的差异变小。随机过程成分（即扩散限制）的差异较小，导致增温条件下两个地层的真菌群落结构相似。本研究加深了我们对增温对草原微生物群落影响的理解，并为增温情景下上下土壤层之间微生物组装的潜在机制提供了更多见解。
