Test Design Lighthouse


China Sea

Yellow Sea, East China Sea, South China Sea

The Yellow Sea got its name from the yellowish discoloration caused by the vast amount of particulate material discharged by the Huang He River. (Photo: NASA, SeaWIFS)

For this particular purpose we put together the following waters of the southwestern Pacific Ocean referring to as the China Sea: the extremely flat and shallow Yellow Sea to the North, the continental marginal East China Sea to the east, and the deep South China Sea in the south.

 

 

The Yellow Sea

 

The Yellow Sea is a semi-enclosed southwestern North Pacific embayment located between China and Korea with the Gulf of Liaodong to the northeast and the West Korea Bay to the north. Several islands lie along the Korean coast, while extended sand shoals are sited along the Chinese coastline. The sea is former land submerged during post glacial sea level rise roughly 10,000 years ago.

 

The Yellow Sea got its name from the yellowish discoloration caused by the vast amount of particulate material discharged by the Huang He River. Due to the discharge of nutrient-rich river waters, in former times the Yellow Sea was very rich in bottom fish species and shrimps. However, today farmers protect their fields more intensively against erosion causing a lack of nutrients in the Yellow Sea and dramatic decreases in shrimp catches.

 

The hydrographic properties, circulation patterns and flow strengths of the Yellow Sea are driven by the proximity to the Kuroshio Current and by the seasonal variation of the Monsoon winds. Major currents are a northwest directed branch of the Kuroshio called the Yellow Sea Current, the southward flowing China Coastal Current, and an unnamed current flowing southward along the west coast of Korea that carries low salinity water from the Bohai Gulf.

 

The climate of the Yellow Sea region shows extreme variations. Very cold, dry winters alternate with wet and warm summers. This dramatic seasonal change is caused by winter and summer Monsoon conditions. Typhoons – like Hurricanes in the equatorial Atlantic – prevail during summer months and cause severe damages along the coastlines. Extreme precipitation events may cause catastrophic river floods.

 

During winter, parts of the inner Yellow Sea freeze over effected by the severe cold of the Asian continent. During spring break-up, river ice drifts far out into the shallow Bohai waters.

 

Besides fishery and coastal farming, regional maritime trade and traffic are the most dominant economic sources.

 

 

The sediment-laden waters of central China's Yangtze River are emptying into the East China Sea. (Photo: NASA, SeaWiFS).

East China Sea

 

The East China Sea lies south of the Yellow Sea. From a broad and shallow shelf in the west the sea steeply slopes eastwards towards greater depths in the Okinawa Trough. The Nansei-Syoto Ridge separates the East China Sea from the Philippine Sea.

 

The Kuroshio Current dominates the flow conditions of the East China Sea. Oceanography, climate and ecology of the sea are comparable to that of the Yellow Sea and South China Sea regions.

 

 

South China Sea

 

The South China Sea is a regional sea in the southwestern Pacific Ocean including the Gulf of Thailand and the Gulf of Tonkin and is centered between Vietnam, Thailand, the Malay Peninsula, Borneo, the Philippines and Taiwan. The sea is connected to the Andaman Sea via the Strait of Malacca, to the Java Sea via the Karimata Strait, to the Philippine Sea via Luzon Strait and to the Sulu Sea via the Balabar Strait and the Mindoro Channel.

 

The southwestern part of the South China Sea is a shallow and flat shelf sea, while the much deeper eastern basin has a lively seafloor. The shelves along the Chinese and Vietnam coasts partly steeply break towards greater depths.

 

The area includes more than 200 small islands with the majority located in the Paracel and Spratly Island chains. Many of these islands are partially submerged islets, rocks, and reefs that are little more than shipping hazards and not suitable for habitation.

 

November 11. 2001: Typhoon Lingling off the coast of Vietnam. (Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC)

The northeast Monsoon between December and February and the southwest Monsoon between June and August change the surface water circulation pattern with predictable regularity and significantly influence the regional climate.

 

The South China Sea region is the World's second busiest international sea route. More than half of the World's supertanker traffic passes through the regional waters. In addition, the South China Sea region contains oil and gas resources, which are strategically located near large energy-consuming and fast developing countries. According to the huge oil and gas reserves the South China Sea is referred to as ”the second Persian Gulf”.

 

Most people of the area work in fishing, marine transportation, offshore exploration and mining of mineral and non-mineral resources as well as recreation and tourism. Fishery industry concentrates on coastal cultivation of oysters and shrimp as well as on deep sea fishing for tuna and other migratory species.

 

Besides intensive economic activities the South China Sea is also a unique ecosystem. Coral reefs host several thousand different species of organisms thus playing an important role for the biological diversity. The still occurring dugong is a sensitive indicator for environment health.

 

However, the region is becoming more and more a sink for regional environment pollution. Transit vessels are increasingly responsible for oil spills and waste dumping. More regional environment problems include over fishing and smoke haze from forest fires and factories.

 

A diminishing fish catch from year to year threatens the extensive fishing industry and many fishermen are forced to practice more aggressive or even illegal fishing techniques like blasting and cyanide poisoning or venture further out towards new fishing grounds.

 

Increasing sedimentation from land development and coastal erosion further degrades coral habitats, while coral reefs are ravaged and plundered to provide building materials and ornamental commodities.

 

 

The Chinese Mitten Crab - A Successful Worldwide Invader

 

The Chinese mitten crab is a burrowing crab whose native distribution are the coastal waters and estuaries of the Yellow Sea off Korea and China. The main identifying features of the roughly 80 millimeter large crabs are the dense patches of hair on claws of larger juveniles and adults, hence the name mitten crab.

 

The Chinese mitten crab has a long and successful history as an invader. The crab was accidentally introduced to German waters via vessel ballast tanks in the early 1900s. In the 1920s and 1930s, the population strongly increased and the crabs rapidly expanded their distribution to many northern European rivers and estuaries. Most recently, the River Thames in England experienced a population explosion of the crabs.

 

In 1992, commercial shrimp trawlers in southern San Francisco Bay collected the first mitten crabs on the US West Coast. Since then, the mitten crab has spread rapidly, established in the San Francisco Bay, and spread to many river areas upstream of the mouth.

 

Mitten crabs are omnivores, feeding both on plants and animals. While juveniles take primarily vegetation, the mature crabs increasingly prey upon animals like small invertebrates including worms, clams and shrimps. The mitten crab has profound impacts on ecosystems through predatory and competition, and could completely change the structure of fresh and brackish water invertebrate biological communities. The crabs also predate on salmon and sturgeon eggs and juveniles. Furthermore, they damage fishing nets. In tidal areas, mitten crabs burrow into banks for protection from predators and desiccation during low tides. This burrowing activity may increase erosion and instability of levees and riverbanks. Predatory fishes, including mature sturgeon and catfish as well as bullfrogs, raccoons, river otters and wading birds may prey upon the crab.

 

Mitten crabs are adept walkers on land. If blocked by dams, weirs or other obstacles during migration, they move readily across banks or levees to bypass them. In Germany, large numbers of mitten crabs left the water at night and occasionally wander streets and enter houses. In California, mitten crabs were found on roads and airport runways, in parking lots, yards and swimming pools.

 

Besides severe ecological and commercial damages the mitten crab poses also a potential human health threat. The crab is an intermediate host for the Oriental lung fluke, and mammals, including humans, can become infested by eating raw or poorly cooked mitten crabs.

 

 

To top

More information:

LF-Project:

  • South Korea: For A Sustainable Saemangeum