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海洋环流如何将塑料垃圾聚集成巨型垃圾带？

Ocean gyres are large, slow-moving circular currents driven by wind patterns and Earth’s rotation.
Five major subtropical gyres trap floating debris in their calm central zones called 'convergence zones'.
Plastic fragments break down into microplastics but remain buoyant due to low density and surface tension.
Current models show that over 80% of ocean plastic originates from land-based sources via rivers.
The North Pacific Gyre hosts the largest accumulation zone, known informally as the Great Pacific Garbage Patch.
Satellite tracking and drifting buoys help scientists map transport pathways and residence times.
Marine organisms mistake microplastics for plankton, introducing toxins up the food chain.
Cleanup efforts focus on intercepting riverborne waste before it reaches open ocean circulation.
Biodegradable alternatives fail in seawater because salt and cold inhibit microbial breakdown.
Oceanographers combine fluid dynamics simulations with field sampling to predict future accumulation hotspots.