School of Geography and Ocean Science, Nanjing University, Nanjing, 210023, China; Ministry of Education Key Laboratory for Coastal and Island Development, Nanjing University, Nanjing, 210023, China.
School of Geography and Ocean Science, Nanjing University, Nanjing, 210023, China; Ministry of Education Key Laboratory for Coastal and Island Development, Nanjing University, Nanjing, 210023, China; Collaborative Innovation Center of South China Sea Studies, Nanjing University, Nanjing, 210023, China.
Environ Pollut. 2022 Sep 15;309:119824. doi: 10.1016/j.envpol.2022.119824. Epub 2022 Jul 20.
Marine microplastic pollution has become a major global concern in recent years and the fate of microplastics in the ocean is a hot issue of research. We investigated microplastic pollution in surface sediments in the northern South China Sea to explore its distribution characteristics and influencing factors across the continental shelf, continental slope, and deep-sea environments. It was found that the microplastic abundance of surface sediments was 130.56 ± 40.48 items/kg. The average abundance of microplastics in all three topographic areas gradually decreased with increasing distance offshore. However, the differences in microplastic diversity indices between the three areas were not significant and were higher than those in other seas of the world, indicating that the waters of the northern South China Sea are rich in microplastics from complex sources, with more pollution input channels. In the continental shelf, fibrous and low density microplastics accounted for the largest amount, with a low degree of microplastic aging, and were mostly transported by suspended-load. These microplastics were mainly influenced by human activities. In the deep sea, microplastics with higher density were the most abundant and the number of fibrous microplastics was fewer, while the average size was larger, mainly influenced by the bottom currents. These microplastics underwent long-term bedload transport. In the continental slope, the main factors affecting the distribution of microplastics were more complex. In addition to pollution by human activities, the slope also receives microplastic materials carried by bottom currents; therefore, the composition of microplastics in the slope combines those characteristics of microplastics in both the continental shelf and deep-sea areas. The findings of this study indicate that the South China Sea is affected by complex pollution sources under the dual effects of human activities and natural conditions; in particular, the pollution situation in the deep-sea area needs extensive attention.
海洋微塑料污染近年来已成为一个全球性重大问题，而海洋中微塑料的命运则是一个热门研究议题。本研究调查了南海北部表层沉积物中的微塑料污染，以探究其在陆架、陆坡和深海环境中的分布特征及其影响因素。结果表明，表层沉积物中的微塑料丰度为 130.56 ± 40.48 项/kg。在所有三个地形区域，微塑料的平均丰度均随离岸距离的增加而逐渐降低。然而，三个区域之间微塑料多样性指数的差异并不显著，且高于世界其他海域，表明南海海域的微塑料来源复杂，污染输入通道较多。在陆架区，纤维状和低密度微塑料的含量最大，微塑料老化程度较低，主要通过悬浮物输送。这些微塑料主要受人类活动的影响。在深海区，高密度微塑料的丰度最高，纤维状微塑料的数量较少，而平均粒径较大，主要受底流影响。这些微塑料经历了长期的底载输运。在陆坡区，影响微塑料分布的主要因素更为复杂。除了人类活动造成的污染外，坡地还接收由底流携带的微塑料物质；因此，坡地微塑料的组成结合了陆架和深海地区微塑料的特征。本研究结果表明，南海受人类活动和自然条件双重影响下的复杂污染源的影响；特别是深海地区的污染状况需要广泛关注。
