Work

Distribution, sources, and transport of microplastics in a karst river of Southwest China

Year: 2025

Type: article

Abstract: Microplastics (MPs) have emerged as a significant pollutant in riverine ecosystems, yet their transport and distribution in karst rivers remain largely unexplored. This study examines MPs (20–500 μm) in surface water and sediments of the Wuma River, a karst river in Southwest China. Key findings indicate that abundance of MPs ranged from 4 to 122 n/L in surface water and 1,702.25 to 16,594.73 n/kg in sediments, with fragments (~90%) dominating. More than 85% of MPs fall within the 20–100 μm size range, with polyurethane (PU) and polyethylene terephthalate (PET) as the most prevalent polymers. MPs mainly originate from residential activities, agriculture, riverbank tourism, and tire and road abrasion. Karst river channel characteristics play a significant role in MPs retention. Overflow dams increase retention of smaller-sized MPs (20–50 μm), while underground river networks, large boulders, and riparian vegetation influence downstream movement and redistribution. Additionally, river dredging effectively reduces MPs accumulation in sediments. The results advances understanding of MPs behavior in karst fluvial systems, emphasizing the necessity for targeted mitigation strategies to protect these ecologically fragile environments.

Source: Environmental Technology & Innovation

DOI: 10.1016/j.eti.2025.104252

Authors: YingZeng Yang, Xiao Ma, Shaoqi Zhou, Laifeng Zhou

Institutions: Guizhou University, Moutai Institute

Language: English

Topic: Microplastics and Plastic Pollution

Subfield: Pollution

Field: Environmental Science

Domain: Physical Sciences

SDG: Clean water and sanitation

Open Access status: gold

Estimated APC paid: $2,930