Zhang Mei, Zhang Ruixi, Song Riquan, An Xilong, Chu Guixin, Jia Hongtao
College of Grassland Science, Xinjiang Agricultural University, Urumqi, China.
School of Life Science, Shaoxing University, Shaoxing, China.
Front Microbiol. 2022 Oct 21;13:1019023. doi: 10.3389/fmicb.2022.1019023. eCollection 2022.
Aridity is increasing in several regions because of global climate change, which strongly affects the soil microbial community. The soil -harboring bacterial community plays a vital role in soil P cycling and P availability. However, the effect of shifts in aridity on the community is largely unknown. Here, based on high-throughput sequencing technology, we investigated the response patterns of the diversity, co-occurrence networks, and assembly mechanisms of the soil communities along a natural aridity gradient in adjacent pairs of natural and disturbed grasslands in Inner Mongolia, China. The results showed that the α-diversity of the community first increased and then decreased with increasing aridity in the natural grassland, while it linearly increased as aridity increased in the disturbed grassland. The community dissimilarity significantly increased with increased aridity, exhibiting a steeper change rate in the disturbed grassland than in the natural grassland. Increased aridity altered the community composition, leading to increases in the relative abundance of but decreases in . The composition and structure of the community showed significant differences between natural and disturbed grasslands. In addition, the network analysis revealed that aridity improved the interactions among taxa and promoted the interspecific competition of microorganisms. The community assembly was primarily governed by stochastic processes, and the relative contribution of stochastic processes increased with increasing aridity. Furthermore, disturbances could affect -harboring bacterial interactions and assembly processes. Overall, our findings fill an important knowledge gap in our understanding of the influence of aridity on the diversity and assembly mechanism of the soil community in grassland ecosystems, and this work is thus conducive to predicting the community and its ecological services in response to future climate change.
由于全球气候变化，一些地区的干旱程度正在加剧，这对土壤微生物群落产生了强烈影响。土壤中的细菌群落对土壤磷循环和磷有效性起着至关重要的作用。然而，干旱变化对该群落的影响在很大程度上尚不清楚。在此，基于高通量测序技术，我们在中国内蒙古相邻的天然和扰动草原对中，沿着自然干旱梯度研究了土壤细菌群落的多样性、共现网络和组装机制的响应模式。结果表明，在天然草原中，细菌群落的α多样性随干旱程度增加先增加后降低，而在扰动草原中则随干旱程度增加呈线性增加。细菌群落的差异随着干旱程度的增加而显著增加，在扰动草原中的变化率比天然草原更陡。干旱加剧改变了细菌群落组成，导致[具体细菌名称1]的相对丰度增加，但[具体细菌名称2]减少。天然草原和扰动草原之间的细菌群落组成和结构存在显著差异。此外，网络分析表明，干旱增强了细菌类群之间的相互作用，促进了细菌微生物的种间竞争。细菌群落组装主要受随机过程控制，且随机过程的相对贡献随干旱程度增加而增加。此外，扰动会影响土壤细菌的相互作用和组装过程。总体而言，我们的研究结果填补了我们在理解干旱对草原生态系统土壤细菌群落多样性和组装机制影响方面的重要知识空白，因此这项工作有助于预测细菌群落及其生态服务对未来气候变化的响应。
