[Occurrence Characteristics and Ecological Risk Assessment of Microplastic Pollution in the Yellow River Basin]

Area of Science:

• Environmental Science
• Ecotoxicology
• Water Quality Assessment

Context:

• The Yellow River, China's "mother river," faces significant microplastic (MP) pollution.
• Understanding MP pollution status and ecological risks is crucial for the Yellow River Basin.
• Existing data on MP distribution and risk at a watershed scale is limited.

Purpose:

• To investigate the spatial distribution and composition of MPs in the Yellow River Basin.
• To establish a comprehensive MP investigation and evaluation system at the watershed scale.
• To assess the absolute ecological risk of MPs using a two-dimensional risk assessment matrix.

Summary:

• Microplastic abundance ranged from 0.49-350,280.00 × 10^3 items·m^-3, with higher concentrations in tributaries and the estuary.
• MPs were predominantly fibers and fragments (0-1,000 μm), colored and transparent.
• 77.78% of the assessed area was classified as high-risk, with Liujiaxia Reservoir identified as a critical water source area.

Impact:

• Provides a comprehensive watershed-scale assessment of microplastic pollution and ecological risk.
• Highlights the urgent need for targeted management strategies in high-risk zones, particularly tributaries and the Yellow River estuary.
• Identifies Liujiaxia Reservoir as a priority area for monitoring and potential remediation efforts to safeguard water resources.