Distribution characteristics of marine litter on the sea bed of the East China Sea and the South Sea of Korea

The types, quantities, and distribution of marine litter found on the sea bed of the East China Sea and the South Sea of Korea are surveyed. Surveys were evaluated using bottom trawl nets during 1996–2005 cruises. Mean distribution densities were high in coastal seas, especially in the South Sea of Korea offshore from Yeosu, with 109.8 kg km−2, and low in the East China Sea, with densities of 30.6 kg km−2. Fishing gear, such as pots, nets, octopus jars, and fishing lines, accounted for about 42–72% and 37–62% of litter items in the East China Sea and the South Sea of Korea, respectively, whereas the contributions of rubber, vinyl, metal, plastic, glass, wood, and clothing were below 30% mainly. Rope and drum composition fluctuated greatly, between 54% and 0%. Eel and net pots dominated the marine debris of the South Sea of Korea, and some vinyl, plastics, and fishing gear made in Korea, China, and Japan were collected in abundance in the East China Sea. Fishing gear was probably discarded into the sea, deliberately or inadvertently, by fishing operations. A comprehensive joint approach by Korea, China, and Japan is needed for the continuous monitoring of input sources, the actual conditions, and the behavior of marine litter for protection against litter pollution and fisheries resource management in this area.