Collins Scott F, Norton Andrea
Department of Natural Resources Management, Texas Tech University, Lubbock, TX, 79409, USA.
Woodwell Climate Research Center, Falmouth, MA, 02540, USA.
Sci Rep. 2024 Jul 31;14(1):17741. doi: 10.1038/s41598-024-68516-2.
Cities generate large amounts of plastic waste and thus are often major sources of plastic pollution. Microplastics (particles < 5 mm) are a growing ecological concern as they are readily transported through the environment by wind, flowing water, and other transport processes. Here, we report the findings of an intensive field study that tested associations between prevailing winds and the distribution of plastic pollution around urban lakes (n = 20 lakes) in offshore sediments, shoreline sediments, and surface waters. We tested and found support for the hypothesis that prevailing winds influence the distribution of plastics around lakes. Overall, lakes had greater proportions of macroplastics (i.e., large plastic trash) and microplastics in sediments collected along northern lake shorelines. Notably, we found that macroplastic trash and total microplastics were, respectively, 1.7 and 3 times more abundant in sediments sampled along northern shorelines. Contrary to our expectation, we also found that microplastics in offshore sediments were in greater proportions along western lake shorelines, indicating that wind-driven processes might not explain the distribution of plastics in all lake zones. Furthermore, we observed no discernable patterns within lake surface waters and only captured a handful of suspended microplastic fragments and films from the water column. Overall, our findings revealed that the heterogeneous accumulation of plastic pollution at a lake is influenced, in part, by wind-driven processes. Moreover, these patterns extend across a network of lakes that were distributed across an urbanized landscape.
城市产生大量塑料垃圾，因此往往是塑料污染的主要来源。微塑料（颗粒<5毫米）正日益引起生态关注，因为它们很容易通过风、流水和其他运输过程在环境中传播。在此，我们报告一项密集实地研究的结果，该研究测试了盛行风与城市湖泊（n = 20个湖泊）周边近海沉积物、海岸线沉积物和地表水塑料污染分布之间的关联。我们对盛行风影响湖泊周围塑料分布这一假设进行了测试并发现了支持证据。总体而言，在沿湖北岸线采集的沉积物中，湖泊的大塑料（即大塑料垃圾）和微塑料比例更高。值得注意的是，我们发现沿北岸线采样的沉积物中，大塑料垃圾和总微塑料分别多出1.7倍和3倍。与我们的预期相反，我们还发现，在湖泊西部海岸线附近的近海沉积物中微塑料比例更高，这表明风力驱动过程可能无法解释所有湖区塑料的分布情况。此外，我们在湖泊表层水中未观察到明显模式，仅从水柱中捕获了少量悬浮的微塑料碎片和薄膜。总体而言，我们的研究结果表明，湖泊中塑料污染的异质积累部分受到风力驱动过程的影响。此外，这些模式延伸至分布在城市化景观中的一系列湖泊。
