Research Trend of Aging Biochar for Agro-environmental Applications: a Bibliometric Data Analysis and Visualization of the Last Decade (2011–2023)

Journal of Soil Science and Plant Nutrition https://doi.org/10.1007/s42729-023-01456-4 REVIEW Research Trend of Aging Biochar for Agro‑environmental Applications: a Bibliometric Data Analysis and Visualization of the Last Decade (2011–2023) Hafeez Ur Rahim1 · Enrica Allevato2 · Emanuele Radicetti1 · Francesco Carbone3 · Silvia Rita Stazi1 Received: 19 June 2023 / Accepted: 22 August 2023 © The Author(s) 2023 Abstract The copious amounts of data generated through publications play a pivotal role in advancing Science, Technology, and Policy. Additionally, they provide valuable and detailed information on research topics, emerging thematic trends, and critical issues that demand increased focus and attention. Over the last few decades, biochar has produced an extensive body of high-quality papers and played a crucial part in achieving the long-term Sustainable Development Goals of the 2030 agenda of the United Nations about “Climate Change,” “Sustainable Agriculture,” “Environmental Sustainability,” “Zero Hunger,” “Human Wellbeing,” and “Circular Bioeconomy”. However, most of the research is on biochar that has been modified or functionalized using various chemical reagents or catalysts and reported widely in peer-reviewed, high-quality journals. No prior work analyzed the bibliometric data on aging biochar with (a)biotic processes. This study presents an innovative datadriven bibliometric analysis technique and paradigm for extracting the essence of the available peer-reviewed literature data to offer new perspectives on the research opportunities and potential of aged biochar for agro-environmental applications. The bibliometric data analysis indicates that aging biochar research for agro-environmental applications received attention, advanced, and resulted in 165 high-quality publications in reputed journals between 2011 and 2023. However, it is evident that there is still a considerable need for further attention in this area. The identification of the research trends/frontiers shows that biochar production effectively employs various biomass resources, aging with different (a)biotic factors, characterization, effects on global climate change, long-term carbon sequestration in soil, soil nutrient dynamics, restoration of multi-polluted soils and sediments, and plant growth all require continuous attention both now and in the future. Keywords Aging biochar · (A)biotic processes · Agro-environmental sustainability · Data-extraction · Bibliometric analysis 1 Introduction Nowadays, a shift in agricultural management and public policies towards a more Sustainable Development Model is necessary, according to claims that intensive conventional agricultural practices, climate change, rapid * Silvia Rita Stazi 1 Department of Chemical, Pharmaceutical and Agricultural Sciences (DOCPAS), University of Ferrara, 44121 Ferrara, Italy 2 Department of Environmental and Prevention Sciences, University of Ferrara (DiSAP), 44121 Ferrara, Italy 3 Department for Innovation in Biological, Agro‑food and Forest Systems (DIBAF), University of Tuscia, 01100 Viterbo, Italy industrialization, and urbanization have caused environmental damage and compromised world food security (Ur Rahim et al., 2021). Countries are enticing researchers to take action and investigate new, effective, green, and sustainable approaches to achieve Sustainable Development Goals (SDGs) concerning, no poverty (SDG-1), zero hunger (SDG-2), good health and well-being (SDG-3), climate action (SDG-13), and life on land (SDG-15) (Rosati et al., 2021; Ur Rahim et al., 2021). Based on these urgent needs, the adoption of by-products of thermo-pyrolysis, specifically biochar, in agro-ecosystems stands out as a promising environmentally friendly material used as a soil amendment for supporting crop development and yield (Brassard et al., 2019). Biochar is a solid, carbon-rich substance created through the pyrolysis of various feedstocks with a limited amount of oxygen and has a well-developed porous structure and 13 Vol.:(0123456789) Journal of Soil Science and Plant Nutrition flexible functionality (Majumder et al., 2023). Several studies showed as biochar supports the shift to Sustainable Development Model easier by promoting climate change mitigation (Lehmann et al., 2021), increasing the amount of carbon in the soil (Novotný et al., 2023; Akbar et al., 2023a), lowering soil pollution (Rahim et al., 2022; Saleem et al., 2023), regulating nutrient and water cycles (Akbar et al., 2023b; Pan et al., 2021), and changing the physicochemical characteristics of soil (Mansoor et al., 2021), improving microbial activity (Palansooriya et al., 2019), enhancing plant performance and agricultural output (Yu et al., 2019). The previously listed benefits are mainly due to biochar’s surface properties and the functional groups that facilitate their apparent performance, but it is impossible to ignore the biochar’s in situ temporal performance in the complex soil system. This could be due to the several biotic and abiotic factors, e.g., temperature variations, precipitation events, and microbial activities, that modify biochar physicochemical and surface properties in the soil through fragmentation, dissolution, and oxidation (Wang et al., 2020). Although biochar research has exploded in recent years, as shown in Fig. 1, up to date the long-term responses of biochar have received far less attention than other research Fig. 1  The review of the trends in peer reviewed papers in BC research 13 areas, such as short-term performances. Once biochar is applied to the soil, it undergoes natural aging processes involving various factors influencing its surface morphology and functional groups. This aging process occurs due to several environmental and soil-related factors and processes, including (i) physical aging, primarily by freeze-thaw cycles, changes in temperature and moisture (these cycles may lead to the expansion and contraction of the biochar structure, potentially affecting its surface properties), aeration (accelerate oxidation processes affecting the surface chemistry of biochar), pH (influence chemical reactions occurring on the surface of biochar), and natural organic substances in soil, which influence the biochar surface morphology and functional groups (Cao et al., 2019; Cheng and Lehmann, 2009; Hale et al., 2011; Yang et al., 2018), (ii) chemical aging, through abiotic oxidation upon exposure to various oxidizing agents, such as, hydrogen peroxide (H2O2), nitric acid (HNO3), sulfuric acid/nitric acid ( H2SO4/HNO3), potassium dichromate (K2Cr2O7), hydrogen peroxide/potassium dichromate (H2O2/K2Cr2O7), phosphoric acid ( H3PO4), and many other (Xia et al., 2023, Han et al., 2018, Chu et al., 2018, Cross and Sohi, 2013; Gámiz et al., 2019a; Huff and Lee, 2016), and (iii) biological aging, biotic degradation Journal of Soil Science and Plant Nutrition and corresponding physical and chemical modifications of biocha (...truncated)