Institute of Marine Science and Technology, Shandong University, Qingdao, China.
Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, China.
Glob Chang Biol. 2021 Dec;27(24):6331-6347. doi: 10.1111/gcb.15891. Epub 2021 Sep 27.
Global warming may alter microbially mediated ecosystem functions through reshaping of microbial diversity and modified microbial interactions. Here, we examined the effects of 5-year experimental warming on different microbial hierarchical groups in a coastal nontidal soil ecosystem, including prokaryotes (i.e., bacteria and archaea), fungi, and Cercozoa, which is a widespread phylum of protists. Warming significantly altered the diversity and structure of prokaryotic and fungal communities in soil and additionally decreased the complexity of the prokaryotic network and fragmented the cercozoan network. By using the Inter-Domain Ecological Network approach, the cross-trophic interactions among prokaryotes, fungi, and Cercozoa were further investigated. Under warming, cercozoan-prokaryotic and fungal-prokaryotic bipartite networks were simplified, whereas the cercozoan-fungal network became slightly more complex. Despite simplification of the fungal-prokaryotic network, the strengthened synergistic interactions between saprotrophic fungi and certain prokaryotic groups, such as the Bacteroidetes, retained these phyla within the network under warming. In addition, the interactions within the fungal community were quite stable under warming conditions, which stabilized the interactions between fungi and prokaryotes or protists. Additionally, we found the microbial hierarchical interactions were affected by environmental stress (i.e., salinity and pH) and soil nutrients. Interestingly, the relevant microbial groups could respond to different soil properties under ambient conditions, whereas under warming these two groups tended to respond to similar soil properties, suggesting network hub species responded to certain environmental changes related to warming, and then transferred this response to their partners through trophic interactions. Finally, warming strengthened the network modules' negative association with soil organic matters through some fungal hub species, which might trigger soil carbon loss in this ecosystem. Our study provides new insights into the response and feedback of microbial hierarchical interactions under warming scenario.
全球变暖可能通过重塑微生物多样性和改变微生物相互作用来改变微生物介导的生态系统功能。在这里，我们研究了 5 年的实验增温对沿海非潮汐土壤生态系统中不同微生物层次群体的影响，包括原核生物（即细菌和古菌）、真菌和 Cercozoa，Cercozoa 是广泛存在的原生动物门。增温显著改变了土壤中原核生物和真菌群落的多样性和结构，此外还降低了原核生物网络的复杂性，并使 Cercozoa 网络碎片化。通过使用跨领域生态网络方法，进一步研究了原核生物、真菌和 Cercozoa 之间的交叉营养相互作用。在增温下，Cercozoa-原核生物和真菌-原核生物二分网络变得简单化，而 Cercozoa-真菌网络变得稍微更复杂。尽管真菌-原核生物网络简化，但某些腐生真菌与某些原核生物群（如拟杆菌门）之间的协同相互作用得到了加强，在增温下这些菌群仍保留在网络中。此外，在增温条件下，真菌群落内部的相互作用相当稳定，这稳定了真菌和原核生物或原生动物之间的相互作用。此外，我们发现微生物层次相互作用受到环境胁迫（即盐度和 pH 值）和土壤养分的影响。有趣的是，在环境条件下，相关微生物群体会对不同的土壤性质做出反应，而在增温下，这两个群体往往会对相似的土壤性质做出反应，这表明网络枢纽物种会对与增温相关的某些环境变化做出反应，然后通过营养相互作用将这种反应传递给它们的伙伴。最后，增温通过一些真菌枢纽物种加强了网络模块与土壤有机质的负相关，这可能会导致该生态系统中的土壤碳损失。我们的研究为微生物层次相互作用在增温情景下的响应和反馈提供了新的见解。
