降水中的微塑料:分析高度对大气沉积模式的影响
Abdul Warrish1, Kshitij Chaturvedi2, Prasant Arya2
1Aquatic Ecology Lab, Department of Himalayan Aquatic Biodiversity, Hemvati Nandan Bahuguna Garhwal University (A Central University), Srinagar-Garhwal, Uttarakhand, 246174, India.
Bulletin of environmental contamination and toxicology
|November 30, 2025
概括
大气中的微塑料 (MP) 随着印度中部喜马拉雅山脉的高度而减少. 较高的海拔地区接收的MP较少,较小,通常是较轻的聚合物,这表明从城市来源的远程运输.
科学领域:
- 环境科学 环境科学
- 大气化学 大气化学
- 生态毒理学 生态毒理学
背景情况:
- 微塑料 (MP) 污染越来越令人担忧,通过大气运输和沉积到达遥远的生态系统.
- 了解环境因素 (如海拔) 如何影响MP沉积对于评估污染途径至关重要.
研究的目的:
- 调查海拔对微塑料度,尺寸分布和大气沉积中的聚合物组成的影响.
- 为了分析雨量和降雪样本在中部喜马拉雅山脉的高度梯度.
主要方法:
- 收集了印度中部喜马拉雅地区八个地点 (445米至3378米) 的降雨和降雪样本.
- 采用多阶段选,氧化消化和真空过用于MP隔离.
- 使用光谱学分析了MP度,尺寸分布 (100微米至5毫米) 和聚合物组成的样本.
主要成果:
- MP度与海拔高度呈反向关系,在低海拔 (445米) 处度较高 (高达137MP L-1),在高海拔 (3,378米) 处度较低 (5.5MP L-1).
- 纤维 (74.1%) 主导着来自织品来源的MP类型. 颗粒大小分布随着高度的变化而变化,在较高的海拔地区普遍存在较小的MP (<100微米至1毫米).
- 轻质聚合物 (聚乙烯,聚烯) 在较高的地点更常见,而较重的聚合物 (PVC,PTFE) 则集中在较低的海拔地区.
结论:
- 高度是控制大气微塑料沉积的一个重要因素.
- 低海拔的城市地区获得更高的MP度,而偏远的高海拔地区获得更少,更细微的颗粒,可能被运输在很远的距离.
- 这些发现强调了细微塑料在远程大气运输中的作用,以及它们到达原始环境的潜力.
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