Institute of Marine Sciences, Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou, 515063, China.
Guangxi Key Laboratory of Marine Environmental Change and Disaster in Beibu Gulf, Beibu Gulf University, Qinzhou, 535011, China.
Environ Pollut. 2024 May 1;348:123817. doi: 10.1016/j.envpol.2024.123817. Epub 2024 Mar 18.
Microplastic is an emerging pollutant and a technical fossil in Anthropocene sediments. Typhoon frequency and intensity have increased due to climate change, which has a major effect on the distribution patterns of microplastics. It is still unknown, though, how the topography of the peninsula affects the reconstruction of the distribution of microplastic in typhoons. Due to frequent typhoons, the Leizhou Peninsula (LZP) in the north part of the South China Sea is an ideal place to study the impact of topographic variations on microplastic distribution during typhoon events. This study investigated microplastics ranging in size from 50 μm to 5 mm in sediment. Microscopic inspection and μ-FTIR tests were used to identify microplastic characteristics from offshore surface sediments before and after typhoons. The average microplastic abundance in offshore sediments decreased from 18 ± 17 items/kg to 15 ± 15 items/kg after typhoons. Results show that typhoons only increase the microplastic abundance in topographically protected areas along the northeast coast of LZP, with no significant difference observed in other regions. The influence of typhoon on the morphological characteristics of microplastics in sediments is more pronounced and widespread, as evidenced by a shift in the predominant shape of microplastics from fibers to fragments and a decrease in size accompanied by an increased abundance within the 100 μm-1 mm fraction. The color of microplastics remained similar before and after typhoons, and the polymer composition of microplastics became more uniform. The alteration of microplastic morphology may be attributed to the enhancement of wave intensity induced by typhoons. This study enhances the comprehension of typhoon-induced impacts on pollutant redistribution, specifically microplastics, thereby providing essential empirical evidence and theoretical foundations for pollution regulation.
微塑料是一种新兴污染物，也是人类世沉积物中的技术化石。由于气候变化，台风的频率和强度增加，这对微塑料的分布模式有重大影响。然而，半岛的地形如何影响台风中微塑料分布的重建还不得而知。由于台风频繁，南海北部的雷州半岛（LZP）是研究地形变化对台风期间微塑料分布影响的理想场所。本研究调查了沉积物中大小在 50μm 至 5mm 之间的微塑料。使用显微镜检查和 μ-FTIR 测试，从台风前后的近海表层沉积物中识别微塑料特征。台风后，近海沉积物中微塑料的平均丰度从 18±17 项/kg 减少到 15±15 项/kg。结果表明，台风仅增加了 LZP 东北海岸地形保护区域的微塑料丰度，而在其他区域则没有明显差异。台风对沉积物中微塑料形态特征的影响更为显著和广泛，表现为微塑料主要形状从纤维变为碎片，尺寸减小，同时 100μm-1mm 粒径范围内的丰度增加。台风前后微塑料的颜色相似，微塑料的聚合物组成变得更加均匀。微塑料形态的变化可能归因于台风引起的波强度增强。本研究增强了对台风引起的污染物再分布（特别是微塑料）影响的理解，为污染治理提供了必要的经验证据和理论基础。
