Research progress in response of soil microorganisms to global warming: based on bibliometric analysis

Abstract:

[Background] Soil microorganisms play a crucial role in the response of terrestrial ecosystem to global warming.[Objective] To unravel the status quo, hotspots, and frontiers of research on the response of soil microorganisms to global warming and to clarify the knowledge structure in this field. [Methods] Based on the 3 189 papers on the response of soil microorganisms to global warming published in Science Citation Index Expanded of Web of Science from 1999 to 2021, the annual number of papers in this field, cited frequency of the papers, authors, affiliations, countries, subjects, and keywords were visualized by Vosviewer and CiteSpace.[Results] The number of papers shows an overall increasing trend:first slow increase, then steady increase, and finally rapid increase in detail. The highly cited papers are all published in top international journals, the research outcomes of which have high academic influence. As for interdisciplinary research and collaboration, Environmental Science, Ecology, and Soil Science are the main disciplines, and Multidisciplinary Sciences occupies an important position in this field. Moreover, professors Luo Yiqi, Schuur, and Zhou Jizhong are the core scholars in this field. Cooperation among the authors in the same research team is common. The main affiliations are the Chinese Academy of Sciences, University of California, and the US Department of Energy, with close cooperation among the affiliations. Besides, China, the US, and Europe are the main forces in this field and frequent cooperation among countries in this filed is observed. The research focus is that global warming changes the community structure, diversity, and physiological and biochemical functions of soil microorganisms, further influencing geochemical cycle. The research frontiers are the mechanism of action and regulatory mechanism of soil microorganisms in release of soil carbon pool. [Conclusion] The response and adaptation mechanism of soil microorganisms in different ecosystems to global warming are different. A few studies of microbial carbon function-related genes and interaction of multiple environmental factors are available. Therefore, efforts should be made to carry out research on specific ecosystems and large-scope large-scale long-term positioning research, strengthen the research on microbial carbon degradation- and carbon fixation-related genes, and emphasize the impact of the interaction of multiple environmental factors on soil microbial ecological processes.

Key words:soil microorganism;global warming;soil carbon cycle;visualization;research hotspots