Abstract: As a key tourist area in Shenzhen, Dapeng Bay faces an annual accumulation of hundreds of tons of beach and marine debris, with cleanup efforts consuming significant manpower and resources. This study focuses on the Dapeng Bay region, establishing a marine numerical model based on the FVCOM (finite volume community ocean model) ocean current model. The simulated flow and wind field data were input into the Lagrangian particle-tracking model OpenDrift to investigate the migration patterns of marine debris in Dapeng Bay, combined with observational data from drift buoys. The results indicate that in April, debris entering the sea from the Xiasha area primarily drifts and accumulates near Dameisha and Xiaomeisha, Yantian Port, and the Ji Ao area of Hong Kong. The floating debris near Dameisha and Xiaomeisha mainly originates from the eastern and northern coasts of Dapeng Bay, with some contributions from areas outside the bay. For debris along the northern and eastern nearshore regions of Dapeng Bay, Yantian Port and the Ji Ao area of Hong Kong are the most likely destinations for accumulation. By comparing experiments across different months and tidal conditions, this study reveals that wind direction dominates the overall movement trajectory of marine debris, wind speed influences drift duration and distance, and tidal variations affect stranding zones and the quantity of debris reaching different areas. The movement and distribution patterns of marine debris in Dapeng Bay uncovered in this study can provide valuable references for debris cleanup operations.

Key words: Dapeng Bay, floating garbage, migration paths, numerical simulations