Comprehensive analysis of heavy metal pollution in the Yellow River Basin from 1980 to 2025: trends, hotspots, and future directions

Abstract

Heavy metal pollution poses potential risks to aquatic ecosystems and public health, making it a widespread concern in the Yellow River Basin—one of China’s major energy bases. Current studies still lack a systematic overview of its progress and prospects. In this work, a bibliometric analysis of research on heavy metal pollution indexed in Web of Science (WOS) and China National Knowledge Infrastructure (CNKI) from 1980 to 2025 was conducted, retrieving a total of 1,830 relevant records. Bibliometrix R package was used for statistical analysis, and VOSviewer along with Biblioshiny for data visualization. This study systematically reviews annual publication trends, maps out primary research fields and academic journals, and identifies influential institutions and co-cited references. On this basis, we trace the evolution of research hotspots, uncover emerging topics and frontier trends, and give a forward-looking reflection on existing problems and future research directions. Overall, as the first systematic bibliometric diagnosis for Yellow River heavy metal research, this study reveals a critical knowledge gap in understanding multi-media transport mechanisms under high-sediment flows, and outlines a prioritized pathway toward refined source apportionment and integrated risk assessment.