Fate, transport, and source of microplastics in the headwaters of the Yangtze River on the Tibetan Plateau

Sansan Feng; Hongwei Lu; Yuxuan Xue; Pengdong Yan; Tong Sun

doi:10.1016/j.jhazmat.2023.131526

Fate, transport, and source of microplastics in the headwaters of the Yangtze River on the Tibetan Plateau

J Hazard Mater. 2023 Aug 5:455:131526. doi: 10.1016/j.jhazmat.2023.131526. Epub 2023 Apr 29.

Authors

Sansan Feng¹, Hongwei Lu², Yuxuan Xue¹, Pengdong Yan³, Tong Sun³

Affiliations

¹ Key Laboratory of Water Cycle and Related Land Surface Process, Institute of Geographic Science and Natural Resources Research, Chinese Academy of Science, Beijing 100101, China.
² Key Laboratory of Water Cycle and Related Land Surface Process, Institute of Geographic Science and Natural Resources Research, Chinese Academy of Science, Beijing 100101, China. Electronic address: luhw@igsnrr.ac.cn.
³ State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin 300072, China.

PMID: 37167873
DOI: 10.1016/j.jhazmat.2023.131526

Abstract

Microplastics (MPs) in the Yangtze River have been drawn increasing attention recently with most merely concentrating on the plain area. This research focuses on the source area of the Yangtze River on the Qinghai-Tibet Plateau (QTP), revealing the occurrence, drivers, sources, and exposure risks of riverine MPs in the Jinsha River (JSR) basin. The results showed that average MP abundances determined were higher in the tributaries than in the of mainstreams. According to the correlation analysis, MP abundance was consistently negatively related to pH and altitude both in water and sediment. However, MPs in two media showed a contrary relationship with river width, which could be explained by the special terrain of plateau rivers and hydrological conditions. After the tributary river flow into the mainstream, the concentration of MPs in the mainstream near the tributary side were significantly lower than that before confluence temporarily. Based on the conditional fragmentation-based model, the cumulative λ value of fibers in surface water along the river divided the JSR into three stages (upstream, midstream, and downstream). Under certain assumptions, the proportions of MPs sourced from three stages were eventually revealed, respectively. This is conducive to better understanding the plateau environmental impacts of MP distribution in the large river.

Keywords: Jinsha river; Microplastic; Sediment; Tibetan Plateau; Water.