School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
Sci Total Environ. 2023 Jan 15;856(Pt 2):159256. doi: 10.1016/j.scitotenv.2022.159256. Epub 2022 Oct 5.
Mangroves in tropical and subtropical regions worldwide are recognized as important sinks for microplastics (MPs). However, recent studies have focused on surface sediments, and in China, the vertical distribution and characteristics of MPs in mangrove sediments remain poorly understood. In this study, sediment cores of 100 cm depth were collected from six representative mangroves in China to investigate MPs via chronological analysis. Futian had the highest abundance of MPs (0-3123 n/kg), followed by Dongfang, Yunxiao, Zhanjiang, Dongzhaigang and Fangchenggang. The earliest MPs occurring in mangroves were dated back to 1955, and their abundance increased exponentially from bottom to surface sediments. MPs were mainly white in color, fiber-shaped, 1000-5000 μm in size, and of polypropylene/polyethylene polymer types. Furthermore, the MPs in the urban mangrove also showed a higher diversity in color. The results showed that the MP stocks in the urbanized Futian mangrove reached 1828 mg/m, an order of magnitude higher than in other areas (251 ± 180 mg/m), contributing to 0.0057 % of the carbon storage of the sediment. The abundance of MPs in mangrove sediments is expected to increase by 2.38-9.54 times by 2030, and therefore deserve further attention.
全球热带和亚热带地区的红树林被认为是微塑料（MPs）的重要汇。然而，最近的研究集中在表层沉积物上，而在中国，红树林沉积物中 MPs 的垂直分布和特征仍知之甚少。本研究从中国六个有代表性的红树林中采集了 100 厘米深的沉积物岩芯，通过时间序列分析来研究 MPs。福田的 MPs 丰度最高（0-3123 n/kg），其次是东方、云霄、湛江、东寨港和防城港。红树林最早出现的 MPs 可追溯到 1955 年，其丰度从底部到表层沉积物呈指数增长。MPs 主要呈白色，纤维状，大小为 1000-5000μm，属于聚丙烯/聚乙烯聚合物类型。此外，城市红树林中的 MPs 在颜色上也表现出更高的多样性。结果表明，城市化福田红树林中的 MP 储量达到 1828mg/m，比其他地区（251±180mg/m）高出一个数量级，占沉积物碳储量的 0.0057%。到 2030 年，红树林沉积物中 MPs 的丰度预计将增加 2.38-9.54 倍，因此值得进一步关注。
