A Bibliometric Analysis of Research on the Sources and Formation Processes of Forest Soil Organic Matter Under Climate Change

Forest soil organic matter (SOM) is a critical component of forest ecosystems and plays a vital role in the global carbon (C) cycle. Global climate change profoundly affects forest SOM dynamics, particularly its sources and formation processes, which are crucial initial stages of the forest soil C cycle. Therefore, understanding these processes and the impacts of climate change is essential for developing effective forest management strategies and climate policies. In this study, VOSviewer 1.6.18 was used to conduct a bibliometric analysis of research published from 1975 to 2024, retrieved from the Web of Science (WoS) Core Collection database, focusing on the sources and formation processes of forest SOM under climate change. The analysis covers annual publication trends, author co-occurrence networks, publication distributions by country and region, keyword clustering, and evolving keyword trends, integrating both quantitative results and a literature review to provide an understanding of the research progress in the field. The results highlight continuous growth in research publications, which can be categorized into four stages: initial emergence, sustained exploration, rapid development, and deep expansion. A solid theoretical foundation and good research strength have been established, driven by prominent academic groups led by researchers such as Jari Liski, as well as leading countries, including the United States and China. The research progress is divided into four topics: the sources of forest SOM; the formation processes of forest SOM; the impacts of climate change; and measurement methods and model-based analysis techniques, which mainly elaborate upon plant-, microbial-, and soil fauna-derived aspects. Research hotspots have evolved from basic C and nitrogen (N) cycles to in-depth studies involving microbial mechanisms and multiparameter climate change interactive effects. This study provides an overview of the research progress and hotspots in the field, offering basic knowledge and theoretical support for potential future research and climate change mitigation strategies.