Trends in phytoremediation of heavy metals-contaminated soils: A Web of science and CiteSpace bibliometric analysis.

Heavy metals pollution in soils is an urgent environmental issue worldwide. Phytoremediation is a green and eco-friendly way of remediating heavy metals. However, a systematic overview of this field is limited, and little is known about future development trends. Therefore, we used CiteSpace software to conduct bibliometric and visual analyses of published literature in the field of phytoremediation of heavy metals in soils from the Web of Science core collection and identified research hotspots and development trends in this field. Researchers are paying increased attention to phytoremediation of heavy metals in soils, especially environmental researchers. A total of 121 countries or regions, 3790 institutions, 4091 funded organisations and 15,482 authors have participated in research in this area. China, India, and Pakistan are the largest contributors. There has been extensive cooperation between countries, institutions, and authors worldwide, but there is a lack of cooperation among top authors. 'Calcareous soil', 'Co-contaminated soil' and 'Metal availability' are the most intensively investigated topics. 'EDTA', 'Plant growth-promoting Rhizobacteria', 'Photosynthesis', 'Biochar' and 'Phytoextraction' are research hotspots in this field. In addition, more and more researchers are beginning to pay attention to research on co-contaminated soil, metal availability, chelating agents, and microbial-assisted phytoremediation. In summary, bibliometric, and visual analyses in the field of phytoremediation of heavy metals in soils identifies probable directions for future research and provides a resource through which to better understand this rapidly advancing subject.