The migration and accumulation of heavy metals in soil, particularly under environmental stress, significantly impact ecosystem dynamics and environmental risks. A recent bibliometric study by Jiaxiang Wang, Yueyao Li, Yimin Zhou, Jibo Long, Zhuoqing Li, Cheng Qiu, Qinghai Liu, and Ming Lei, published in BioResources, provides a comprehensive overview of research trends in this critical field from 2000 to 2024. Using CiteSpace to analyze 1,768 publications from the Web of Science Core Collection, the study highlights a dynamic evolution in research focus.

The analysis indicates a notable shift in research focus over the past two decades. Initially, studies primarily concentrated on identifying pollution and its underlying mechanisms. However, there has been a significant transition towards health risk assessment and material-based remediation strategies. A key emerging area is the increasing attention given to lignocellulose-derived amendments, such as humic acid and biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More, due to their potential in stabilizing soils under various environmental stressors. For example, humic acid, rich in carboxyl and phenolic hydroxyl groups, can form stable complexes with heavy metals, reducing their mobility and bioavailability. Biochar, with its high specific surface area and porous structure, not only immobilizes heavy metals but also enhances crop tolerance by modulating plant antioxidant enzyme activity and nitrogen metabolism. The combination of biochar with nanoscale zero-valent iron has also shown synergistic effects in pollutant removal.

Leading institutions, particularly the Chinese Academy of Sciences, have played a prominent role in this research, demonstrating the highest publication volume (118 papers) and citation frequency (4,281 citations), along with the highest H-index (31). Chinese institutions appear five times among the top ten publishing institutions, underscoring China’s significant influence in this field. Globally, China leads with 497 papers and 14,807 citations, followed by the United States and India. High-impact journals such as Environmental Science and Pollution Research, Science of The Total Environment, and Chemosphere have published the most articles, with Environmental Science and Pollution Research leading with 93 publications. The Journal of Biogeography boasts the highest average citation frequency per article, reflecting high article quality. The generally low self-citation rates across journals suggest a healthy academic publishing landscape in this field.

Keyword clustering and burst analysis highlight emerging core themes. Early research (2000-2010) focused on “heavy metals,” “soil,” “accumulation,” “cadmium,” and “growth,” along with “phytoextraction” and “climate change,” indicating initial explorations into pollution formation and mechanisms. The second phase (2012-2021) saw a shift towards “risk assessment,” “spatial distribution,” “water quality,” and “health risk,” reflecting a deeper investigation into impact mechanisms and the use of materials for soil stabilization. More recently (2015-2024), keywords like “drought stress,” “biochar,” “salt tolerance,” “responses,” and “plant growth” have shown high emergence intensity, representing cutting-edge research and future trends.

The field’s short citation half-life, averaging approximately 2.85 pm 1.25 years, and frequent keyword bursts confirm its status as a rapidly developing research frontier. This rapid renewal pace underscores the high level of attention researchers place on the latest methods and discoveries in addressing complex environmental challenges. The study concludes that the field has evolved towards multidisciplinary integration, combining environmental science, engineering, and soil science to offer innovative and holistic solutions for heavy metal pollution. Future research is expected to continue focusing on advanced strategies, including gene-editing technologies and functional microbial consortia, and the roles of lignocellulose-derived soil amendments in stabilizing soils and enhancing remediation efficacy under stress conditions.

Source: Wang, J., Li, Y., Zhou, Y., Long, J., Li, Z., Qiu, C., Liu, Q., & Lei, M. (2025). Environmental Dynamics and Risk: Bibliometric Insights into Soil Heavy Metal Accumulation Under Environmental Stressors. BioResources, 20(3), 6713-6735.