Typhoon-induced turbulence redistributed microplastics in coastal areas and reformed plastisphere community

摘要

The increasing microplastic pollution together with the plastisphere-associated ecological threats in coastal areas have aroused global concern. Tropical cyclones have been increased in both frequency and intensity under global warming, causing intense impact on the microplastics distribution and the structure of coastal ecosystems. However, until most currently, the extent to which typhoon impacts the microplastics and plastisphere community remains poorly known. This study analyzed the effects of Typhoon Wipha (Code: 1907) on microplastics abundance and composition in surface water and sediment crossed coastal areas of Shenzhen. Here we found a significant typhoon-induced increase in microplastics abundance in surface water, whereas an opposite trend was observed in sediment. Despite the evident transportation of microplastics from sediment to surface water by agitation, a possible microplastics influx was introduced by typhoon as evidenced by the large attribution of unknown force in source tracking analysis. Furthermore, typhoon had adeptly uniformed the plastisphere community in the sediment along the 190 km costal line overnight. A significant increase of nitrogen fixer, Bradyrhizobiaceae, was observed ubiquitously after typhoon, which might alter the nitrogen cycling and increase eutrophic condition of the coastal ecological system. Together, this study expanded the knowledge about the impact of typhoon-induced influx of the microplastics on coastal biogeochemical cycling. Moreover, the microplastics and the plastisphere compositional pattern revealed here will underpin future studies on adsorption behavior, interfacial processes and ecotoxicity of the coastal microplastic pollution.