Abstract:
No anthropogenic pollutant is more widespread in the aquatic and terrestrial environment than microplastic; however, there are large knowledge gaps regarding its origin, fate, or temporal variations in the oceans. In this study, we analyzed sediment trap material from the deep subtropical Northeast Atlantic (2000 m) in a long-term record (2003-2015) to assess the role of the deep ocean as a potential sink of microplastics. Microplastic particles were identified in all 110 analyzed samples with flux rates of 1.13-3146.81 items d-1 m-2. Calculated microplastic mass fluxes ranged between 0.10 and 1977.96 μg d-1 m-2, representing up to 8% of the particle flux. Between years, the composition of the different polymers changed significantly, dominated by polyethylene, whose amount was correlated with the lithogenic input. The correlation between polyethylene and the lithogenic fraction was attributed to an air transport pathway from northeast Africa and surrounding regions. The second most abundant polymer detected in our study was polyvinyl chloride, which is not correlated with lithogenic or biogenic particle flux fractions. Instead, we observed seasonality for polyvinyl chloride with recurring high fluxes in winter before the plankton bloom and significantly lower amounts in summer. Other polymers identified were polypropylene, polyethylene terephthalate, and lower numbers of polystyrene and polymethyl methacrylate. The average microplastic particle size for all samples and polymers was 88.44 ± 113.46 μm, with polyethylene and polyvinyl chloride having the highest proportion of small particles (<100 μm). Our findings provide first insights into temporal variations of sinking microplastics, which are crucial for understanding the fate of plastic in the oceans.
摘要:
在水生和陆地环境中,没有人为污染物比微塑料更普遍;然而,关于它的起源有很大的知识差距,命运,或者海洋中的时间变化。在这项研究中,我们在长期记录(2003-2015年)中分析了来自深亚热带东北大西洋(2000米)的沉积物陷阱物质,以评估深海作为微塑料潜在汇的作用.在所有110个分析样品中均鉴定出微塑料颗粒,通量率为1.13-3146.81项d-1m-2。计算出的微塑料质量通量介于0.10和1977.96μgd-1m-2之间,占颗粒通量的8%。几年之间,不同聚合物的组成发生了显著变化,以聚乙烯为主,其数量与成岩输入相关。聚乙烯与成岩部分之间的相关性归因于东北非洲和周边地区的航空运输途径。在我们的研究中检测到的第二丰富的聚合物是聚氯乙烯,与成岩或生物颗粒通量分数无关。相反,我们观察到聚氯乙烯的季节性,在浮游生物盛开之前的冬季反复出现高通量,而在夏季则显着降低。确定的其他聚合物是聚丙烯,聚对苯二甲酸乙二醇酯,和较低数量的聚苯乙烯和聚甲基丙烯酸甲酯。所有样品和聚合物的平均微塑料粒径为88.44±113.46μm,其中聚乙烯和聚氯乙烯具有最高比例的小颗粒(<100μm)。我们的发现为下沉的微塑料的时间变化提供了初步的见解,这对于理解海洋中塑料的命运至关重要。