渔业捕捞及商业航运活动的塑料排放是南海深海塑料污染的主要来源。南海深海微塑料污染始于20世纪80年代，具有明显陆源输入的特征，陆架近岸区域微塑料污染严重。陆坡深海峡谷是塑料/微塑料向深海盆地输运的主要通道，近底浊流在输运中发挥了重要作用。综述了南海海底塑料垃圾深潜研究的最新进展，首次提出了深海塑料垃圾生态系统的概念。
Large deep-sea debris dumps that were never recorded before on the seafloor worldwide have been discovered in the submarine canyons to the north of Xisha trough in the South China Sea (SCS). The plastics primarily came from fishery and navigation activities, as implied by the categories of plastics in the dumps. The pollution history of microplastics reconstructed by 210Pb dating shows that the microplastics pollution started in the 1980's and it is characterized by the terrestrial input. The continental shelf in the SCS is heavily polluted by microplastics. It is further shown that the deep-sea canyons on the continental slope provide important conduits for carrying the microplastics to the deep-sea basin. The turbidity currents play a critical role in the transportation of plastics in the canyon system. This paper reviews recent progresses of studies of plastics and microplastics using manned submersible in the SCS. For the first time, the concept of the deep-sea plastic dump ecosystem is proposed.
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