从沿海流域量化微塑料河流流量-A微塑料评级曲线方法
Clare Murphy-Hagan1, Andrew B Gray1, Samiksha Singh1
1Department of Environmental Sciences, University of California, Riverside, CA, USA.
Journal of environmental management
|October 2, 2025
概括
河流将数十亿个微塑料运送到海洋. 即使在干旱地区,暴风雨也是这种塑料污染的主要途径,这凸显了需要更好地监测流域规模的需要.
科学领域:
- 环境科学 环境科学
- 水文学的水文学
- 生态毒理学 生态毒理学
背景情况:
- 河流是陆地材料 (包括塑料) 进入海洋环境的关键通道.
- 全球微塑料流量模型因数据缺口和规模限制而面临不确定性.
- 了解流域规模的微塑料运输对于有效的环境管理至关重要.
研究的目的:
- 模拟河流支流中的微塑料度-排放动态.
- 量化了加利福尼亚州上纽波特湾的微塑料流量.
- 确定风暴流在微塑料运输中的作用.
主要方法:
- 在两个支流进行了流量集成的河流监测活动.
- 在一系列的溪流排放中收集了微塑料样本.
- 开发了评级曲线,以建模微塑料度-排放关系.
- 整合了2021年水年数据,以计算总微塑料流量.
主要成果:
- 计算了2021年将23-41亿个微塑料总流向上纽波特湾.
- 确定风暴流作为微塑料运输的主导时期,尽管降雨不频繁.
- 证明了在流量估计中考虑流量变化的重要性.
结论:
- 流域规模的微塑料流量模型对于当地环境影响评估至关重要.
- 风暴事件对河流每年的微塑料负载有很大影响.
- 需要改进监测策略,以减少微塑料流量估计的不确定性.
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