Research trend of permafrost microorganisms based on bibliometrics

Abstract:

[Background] The thawing of permafrost caused by global warming accelerates the degradation of soil organic carbon by microorganisms, and the generated greenhouse gases will exacerbate the greenhouse effect to some extent, forming a positive feedback effect on global climate change. [Objective] To compare the research hotspots and trends of permafrost microorganisms at home and abroad, and thus provide a basis for the research and development of this field in the future. [Methods] The relevant literature was searched from Web of Science Core Collection and CNKI. BIBExcel was employed to generate the co-word matrix of high-frequency keywords, and the network of high-frequency words was visualized with UCINET and NetDraw. The clustering analysis of high-frequency words was performed in SPSS. [Results] A total of 839 papers related to permafrost microorganisms were retrieved, including 713 in English and 126 in Chinese. The number of papers published in English and its growth rate were significantly higher than those in Chinese. According to the high-frequency keywords and co-occurrence networks, foreign research focused on the relationship between climate change, greenhouse gases, and microbial community changes, while the Chinese on microbial diversity in permafrost areas. The clustering analysis demonstrated that the papers published in English mainly involved the degradation of organic carbon by microorganisms and its impact on permafrost areas and even the world. In addition, the Martian life with permafrost microorganisms as the research object has been explored. The studies published in Chinese mainly concerned microbial diversity, methane emissions, and microbial degradation of pollutants in permafrost. [Conclusion] The research situation of permafrost microorganisms has both similarities and differences at home and abroad. Although other countries have better research systems and knowledge structures than China, the greenhouse gas emissions of permafrost microorganisms caused by warming have become a common research hotspot at home and abroad.