塑料不仅流入大海:河流运输的动态受潮和浮动植物的影响
R A Lotcheris1, L J Schreyers2, T K L Bui3
1Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden; Hydrology and Environmental Hydraulics, Wageningen University, Wageningen, the Netherlands.
Environmental pollution (Barking, Essex : 1987)
|February 14, 2024
概括
河流塑料污染是动态的,物品经常停止和移动. 水捕获了81%的巨型塑料,影响了潮河流中的运输和保留.
科学领域:
- 环境科学 环境科学
- 生态生态学 生态生态学
- 海洋学 海洋学 海洋学
背景情况:
- 塑料污染是一个全球性问题,河流是废物进入海洋环境的主要通道.
- 潮河流和河口是塑料运输和保留的关键区域,但它们的动力学知之甚少.
- 在这些系统中的单个潮周期内,巨型塑料的行为需要进一步调查.
研究的目的:
- 为了研究巨型塑料在热带潮河中的短期运输,捕获和重新调动动态.
- 了解潮周期对塑料的移动和保留的影响.
- 确定影响河流环境中巨型塑料命运的关键因素.
主要方法:
- 在西贡河的各种潮阶段 (ebb,洪水, neap,春天),GPS追踪器被部署在宏观塑料物品 (> 0.5厘米) 上.
- 追踪数据分析了间歇运输,停车时间和重新动员模式.
- 评估了植被,基础设施和河岸在塑料陷中的作用.
主要成果:
- 巨型塑料呈现间歇性运输,花费49%的时间停止,主要是由于陷入植被,基础设施或银行.
- 大多数物品 (85%) 在10小时内重新调动,这表明周期性停止和运输阶段.
- 双向运输是显著的,平均每日总运输 (8.9公里/天) 是净运输 (2.0公里/天) 的四倍.
- 平均保留时间为21天,81%的物品被困在水中,这凸显了植被的关键作用.
结论:
- 潮动力学在河流中创造了复杂的,双向的巨型塑料运输模式.
- 浮动植物,特别是水,显著影响巨型塑料的保留和运输动态.
- 了解这些动态对于制定有效的策略来减轻河流塑料污染及其向海洋排放至关重要.
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