A scientometric analysis of biochar applications for soil remediation in mining-affected environments: research trends, intellectual structure, and emerging themes.

Abstract

This study conducts a scientometric analysis to explore research trends, intellectual structures, and emerging themes in biochar applications for soil remediation in mining-affected environments from 2014 to 2024. Using bibliometric data retrieved from Scopus and Web of Science Core Collection, a dataset of 6093 unique peer-reviewed articles was analyzed. Descriptive bibliometric indicators, co-authorship and co-citation networks, and keyword co-occurrence patterns were visualized using the Bibliometrix R package and CiteSpace. The findings reveal significant growth in biochar research post-2018, driven by its increasing application in stabilizing heavy metals and improving soil quality. Co-citation cluster analysis identifies key thematic areas, including "mine soil," "cadmium-contaminated soil," and "dynamic redox conditions," reflecting biochar's role in addressing complex contamination challenges. High citation and sigma values emphasize seminal contributions, particularly on biochar's physicochemical properties and its interactions with heavy metals and microbial communities. Emerging trends highlight growing interest in ecological restoration, microbial dynamics, and innovative approaches such as nanobiochar and machine learning applications. This study provides critical insights into the evolution and interdisciplinary scope of biochar research, offering a roadmap for advancing its application in soil remediation and sustainable land management. Future directions include optimizing biochar formulations for diverse contaminants, integrating computational tools, and exploring its long-term ecological impacts to enhance its transformative potential for environmental sustainability.