AbstractThis article presents a comprehensive review of the publication trends and influential authors in biochar research based on an analysis of articles published between 2008 and April 2023 in the Web of Science database. The study reveals a significant increase in the number of publications on biochar over the years, reflecting a growing interest in this field. The analysis of highly cited papers reveals the presence of tight clusters of authors, with notable leaders from Korea and China. These individuals demonstrate strong connections within their research networks. The article further identifies the most prolific authors in biochar research, highlighting their significant number of papers and citations. However, the article raises concerns about these hyperprolific authors who publish an unusually high number of papers and authors with excessively high citation counts. Such practices raise questions about feasibility, quality, and ethical conduct in research. Further investigation is necessary to understand the mechanisms behind hyperprolific authorship and ensure the maintenance of rigorous scientific inquiry and ethical standards. The article demonstrates the hyperbole in biochar research publications that may include citation manipulation and boosting. It pointed to worrisome practices by some hyperprolific authors in pursue of high citations. Finally, it emphasizes the importance of balancing productivity with the integrity and rigor of research to uphold the principles of quality and responsible scientific practice.IntroductionBiochar is a popular topic in the realm of environmental science and sustainable agriculture, with a growing body of scientific publications dedicated to its study. Biochar refers to the carbon-rich material that is produced through the process of pyrolysis, the controlled decomposition of organic matter in the absence of oxygen (Qian et al. 2015). This highly porous substance has gained significant attention due to its potential benefits in enhancing soil health, sequestering carbon, pollutant removal, and mitigating climate change. Over the years, numerous scientific publications have delved into various aspects of biochar, including its production methods, characterization, applications, and the ecological and agronomic impacts it can have. These publications have highlighted its potential role in sustainable land management practices, offering valuable insights to researchers, practitioners, and policymakers (Allohverdi et al. 2015).Biochar has been hailed as a potential game-changer in our efforts to combat climate change, improve soil health, and even address energy needs. Its appeal lies in its multifaceted benefits and applications which have led to considerable hype in both scientific and popular discourse (Kumar et al. 2023).The excitement surrounding biochar is primarily driven by its potential to mitigate climate change. Biochar is essentially a form of charcoal created by pyrolysis, which stabilizes the carbon in the material, turning it into a form that is not easily decomposed. Consequently, biochar can sequester carbon in the soil for hundreds or even thousands of years, keeping it out of the atmosphere where it would contribute to global warming (Lehmann et al. 2006).Another aspect of the hype is biochar's promise in the field of agriculture. It has been touted as a panacea for degraded soils, with the ability to improve soil fertility, increase agricultural productivity, and enhance resilience to climate change. Biochar can increase soil water-holding capacity, retain nutrients for plant use, and stimulate beneficial soil microbial activity, which collectively enhance soil health and crop yields (Jha et al. 2010).Biochar's potential role in waste management and as a renewable energy source has also led to considerable excitement. The process of creating biochar can help manage organic waste, turning a problem into a solution. Moreover, the heat generated during the pyrolysis process can be harnessed and used as a renewable energy source, adding to the green appeal of biochar (Liu et al. 2019).Despite the hype, it's important to note that while the potential benefits of biochar are impressive, they are not guaranteed (Baveye 2021). The effects of biochar can vary widely depending on a host of factors, including the type of feedstock used to create it, the temperature at which it's produced, how it's applied, and the specific characteristics of the soil it's added to. The burgeoning hype surrounding biochar has not only caught the attention of the public and policymakers, but has also sparked significant interest within the scientific community. This interest has led to a surge in the publication of research papers exploring various aspects of biochar (Baveye 2021). However, this proliferation of research also underscores the complexity of biochar science, as the results often reveal a nuanced picture of biochar's effects that can depend heavily on specific conditions and applications. Professor Baveye from Paris University called "hyperbole" in discussions around biochar to highlight the exaggerated claims made about its potential benefits (Baveye 2021). These claims are overblown or not sufficiently supported by empirical evidence. While it is true that biochar has shown promise in various applications, the variability in its effects due to factors such as feedstock type, production conditions, and soil characteristics means that it may not always deliver the expected benefits. Moreover, the long-term impacts of biochar application on soil and environmental health are not fully understood, leading to further caution (Baveye 2023). Scepticism or caution is called on the tendency to make broad, generalized claims about its benefits. Recent years have also seen a significant increase in the publication of highly cited scientific papers on biochar, which are often considered indicative of their impact and quality in the academic community. Identification of such influential papers can be achieved through databases tracking citation data, or via lists compiled by institutions like Clarivate Analytics.In a recent analysis of characteristics of highly cited papers in Environmental sciences by the author, the study reveals that a small group of exceptionally prolific authors, who publish between 60 to 100 papers annually, dominate the list of highly cited works (Abduh 2023). The majority of these authors work independently, with notable exceptions being two clusters publishing biochar in Korea and China. Network analysis exposes a collective of scientists with an impressive number of highly cited papers, indicating collaboration in publication and citation.The aim of this study is to analyze and understand the landscape of highly cited researchers and authors in the field of biochar. We seek to identify the most prolific contributors, understand their publishing patterns, and examine the nature and extent of their collaborations. By providing insights into the key influencers shaping biochar research, this study aims to illuminate the current state of this rapidly evolving field, and inform future research directions.MethodsThis study investigated publication pattern and highly cited papers focusing on biochar, published between 2008 and April 2023. To achieve this, the Web of Science database, a comprehensive source of academic and scientific literature developed by Clarivate Analytics, was utilized. The database was queried for all papers published under the topic “biochar" during the specified period.The Web of Science database is a trusted tool for research and citation analysis within the scientific and academic communities, as it allows users to track the impact of research, identify trends in academic publishing, and access literature across a wide range of disciplines.Data from the search results were downloaded and exported to MS Excel for preliminary analysis. Subsequently, VOSviewer 1.6.9, a software tool developed by Nees Jan van Eck and Ludo Waltman at Leiden University Centre for Science and Technology Studies (CWTS), was used to analyze and visualize authors' networks.VOSviewer specializes in analyzing bibliometric data, such as citation and co-citation data, and can generate a variety of visualizations, including co-citation maps, term maps, and network diagrams. These visualizations enable researchers to understand the relationships among different research topics, authors, and institutions, and identify patterns and trends in scientific literature. VOSviewer is a widely recognized tool in the scientific and academic communities for bibliometric analysis (Qin et al. 2022).Results and DiscussionPublication trendThis study conducted an extensive review of articles published in international English scientific journals on the topic “biochar” listed in the Web of Science database between 2008 and April 2023. The results of the search produce 29,608 papers equating to an average of over 2,700 papers published annually in the past ten years. Out of these, the top 1% or 1,029 papers were identified as highly cited papers by Web of Science. These highly cited papers are distinguished by receiving a significant number of citations relative to other papers published in the same field and year, placing them in the top 1% based on citation count.To further analyze these 1,029 highly cited papers, a text keyword network was constructed using VosViewer. This network provided insights into the prevalent topics discussed within this influential body of literature (Figure 1).Figure 1 indicates the research in biochar can be grouped in 3 categories: the use of biochar for adsorption or removals of pollutants, the second is on biochar application to soil for plant growth and yield, and the third is on the degradation of biochar. A smaller group of topic indicates the subject on methods of digestion.