The Xiamen Symposium on Marine Environmental Sciences (XMAS 2025)

610 / 2024-09-18 16:20:03

Simulating transport and distribution of marine microplastics in the Bohai Sea using a Lagrangian particle tracking approach

microplastics,Bohai Sea,Largrangian particle tracking

The distribution characteristics and dynamics of the marine microplastics in the Bohai Sea has been simulated using a Lagrangian particle tracking model named Opendrift. The model validation based on the cruise observations and beach litter observations indicates that the model can capture the major spatial distribution trend of both the floating microplastics in the upper ocean and the stranding microplastics along the coastline. The most significant aggregation zones for the floating microplastics are identified in the Liaodong Bay, the northern part of the Bohai Bay mouth, as well as offshore region of the Yellow River estuary. Meanwhile, the major strading areas of microplastics are identified along the coastlines of the Laizhou Bay, the northeastern Liaodong Bay, and the northwestern Bohai Bay. The sensitivity experiments suggest that spatial distribution of micraplastics in the central Bohai Sea, is primarily influenced by ocean currents in spring and summer, while influenced by Stokes drift and wind in autumn. For all seasons, microplastic particles in the coastal Bohai Bay are strongly influenced by ocean currents. In the Laizhou Bay, particle distribution is mainly influenced by the Stokes drift and wind in winter and the ocean currents in summer, respectively. In the Liaodong Bay, all driving forces have discernible impacts on the microplastic abundance distribution. In further studies, more physical-biological interactions for the marine microplastics are needed to be included in this model.