State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China.
State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China.
Sci Total Environ. 2021 Feb 1;754:141948. doi: 10.1016/j.scitotenv.2020.141948. Epub 2020 Aug 24.
There is a rising concern regarding the accumulation of microplastics in the aquatic ecosystems. However, compared to the marine environment, the occurrence, transport, and diffusion of microplastics in freshwater sediment are still open questions. This paper summarizes and compares the methods used in previous studies and provides suggestions for sampling and analysis of microplastics in freshwater sediment. This paper also reviews the findings on microplastics in freshwater sediment, including abundance, morphological characteristics, polymer types, sources, and factors affecting the abundance of microplastics in freshwater sediment. The results show that microplastics are ubiquitous in the investigated sediment of rivers, lakes, and reservoirs, with an abundance of 2-5 orders of magnitude across different regions. Low microplastics concentration was observed in the Ciwalengke River with an average abundance of 30.3 ± 15.9 items/kg. In particular, an extremely high abundance of microplastics was recorded in the urban recipient in Norway reaching 12,000-200,000 items/kg. Fibers with particle size less than 1 mm are the dominant shape for microplastics in freshwater sediment. In addition, the most frequently recorded colors and types are white/transparent, and PE/PS, respectively. Finally, we conclude that the consistency of morphological characteristics and components of microplastics between the beach or marine sediments and freshwater sediments may be an indicator of these interlinkages and source-pathways. Microplastics in freshwater sediment need further research and exploration to identify its spatial and temporal variations and driving force through further field sampling and implementation of standard and uniform analytical methodologies.
人们越来越关注水生生态系统中微塑料的积累。然而，与海洋环境相比，微塑料在淡水沉积物中的存在、传输和扩散仍然是悬而未决的问题。本文总结和比较了以往研究中使用的方法，并为淡水沉积物中微塑料的采样和分析提供了建议。本文还回顾了淡水沉积物中微塑料的研究结果，包括丰度、形态特征、聚合物类型、来源以及影响淡水沉积物中微塑料丰度的因素。结果表明，河流、湖泊和水库的调查沉积物中普遍存在微塑料，不同地区的丰度数量级为 2-5 个。Ciwalengke 河的微塑料浓度较低，平均丰度为 30.3±15.9 个/kg。特别是在挪威的城市受纳水体中，微塑料的丰度极高，达到 12000-200000 个/kg。淡水沉积物中微塑料主要以纤维状、粒径小于 1mm 的颗粒为主。此外，记录到的最常见颜色和类型分别是白色/透明和 PE/PS。最后，我们得出结论，海滩或海洋沉积物和淡水沉积物中微塑料的形态特征和组成的一致性可能是这些相互联系和来源途径的一个指标。需要进一步研究和探索淡水沉积物中的微塑料，通过进一步的野外采样和实施标准和统一的分析方法，以确定其时空变化和驱动力。
