Li Xueyan, Wu Fengrun, Zhang Chengyi, Wang Tao
School of Environmental Science and Engineering, Xiamen University of Technology, Xiamen 361024, China.
State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200241, China.
Toxics. 2024 May 20;12(5):375. doi: 10.3390/toxics12050375.
Coastal beaches are vulnerable to microplastic pollution originating primarily from terrestrial and marine sources or the in situ weathering of plastic waste. The present study investigates the effects of rainfall events on the composition and diversity of microplastics on beaches in Xiamen City on a short-term scale. In the results, the quantity of microplastics in beach sediments was 245.83 ± 11.61 items·kg (mean ± standard error). The abundance of microplastics did not differ after each rainfall event but significantly decreased after multiple rainfall events. When the diversity of microplastics in the coastal area was evaluated, the Shannon-Wiener index and Pielou's index also decreased from 3.12 and 0.64 to 2.99 and 0.62, respectively, after multiple rainfall events. Rainfall had varying effects on microplastics depending on their size and shape, with particles smaller than 500 μm experiencing pronounced reductions. There was a significant negative correlation between the abundance of microplastics and the grain size of sand, but a positive correlation with sediment moisture content. We encourage the consideration of the potential impact of rainfall events during sample collection to ensure the reliability of the data. We also recommend using diversity indexes to help in understanding the influence of physical processes on microplastic distribution and their mechanisms.
沿海海滩易受微塑料污染影响，这些微塑料主要源自陆地和海洋来源或塑料垃圾的原地风化。本研究在短期尺度上调查了降雨事件对厦门市海滩微塑料组成和多样性的影响。结果显示，海滩沉积物中微塑料的数量为245.83±11.61个·千克（平均值±标准误差）。每次降雨事件后微塑料的丰度没有差异，但多次降雨事件后显著降低。在评估沿海地区微塑料的多样性时，多次降雨事件后，香农-威纳指数和皮洛指数也分别从3.12和0.64降至2.99和0.62。降雨对微塑料的影响因其大小和形状而异，小于500微米的颗粒减少明显。微塑料的丰度与沙子的粒度之间存在显著负相关，但与沉积物含水量呈正相关。我们鼓励在样本采集过程中考虑降雨事件的潜在影响，以确保数据的可靠性。我们还建议使用多样性指数来帮助理解物理过程对微塑料分布的影响及其机制。
