•China sediment coastals and estuaries

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CHINA COSTAL SETTING

Coastal areas of the People’s Republic of China comprise an area of approximately 346,983 square kilometers with an 18,000 kilometers coastline stretching across tropical, subtropical and temperate zones from north latitude 20 to north latitude 40 degrees.

Key coastal habitats include mangroves, wetlands, corals, coastal dunes, estuaries, lagoons, salt marshes, sea grass beds, barrier beaches, and other ecosystems.

China’s coastal zone is defined as an area 10 kilometers inland and 15m isobaths seaward from the mean high water tide line.

China’s coastline is contiguous with the Korean and Indochina peninsulas, including more than 6500 islands and islets. Major sea areas include the Yellow sea, East China Sea, and the South China seas.

The coasts and estuaries of China are important environmental, cultural and economic assets. Coastal areas are used for fishing, aquaculture, mineral extraction, industrial development, energy generation, tourism and recreation, and for waste disposal. They are also important for protecting the land from the influence of the sea.

Zone d’extension sedimentaire

CHINA’S COASTAL POPULATION

China’s coastal population totals approximately 600 million people with an average coastal provincial population density of 410 people per square kilometer (2011).

In 2011, 51 cities in the coastal region exceeded 100,000 people. The largest of these are Shanghai (23.4 million), Tianjin (12.5), Guangzhou (10.3) and Hangzhou (6.2).

CHINA SEASHORE BIODIVERSITY

Around 23% of the China’s biodiversity is to be found in the sea (some 120,000 species including sea horses, fish and mammals such as dolphins).

However, coastal areas are under extreme pressure from a wide range of sources and this is reflected in the rapid deterioration of many habitats.

Since 1984, nitrogen inputs to the sea around China have risen by 60% while the estimated total fish stock has declined by 35% in the last 25 years and plaice stocks are now 45% of the size they were in 1949.

ESTUARY FOCUS

China’s estuaries are among the most biologically productive ecosystems on earth. More than two-thirds of the fish and shellfish consumed by humans spend some part of their lives in estuaries.

These ecosystems also provide many other important ecological functions, including acting as filters for terrestrial pollutants and providing protection from flooding.

They also have economic importance as tourist destinations and shipping routes. Millions of people visit the coast each year to boat, swim, bird watch and fish.

Coastal China

CHINA COASTAL ECONOMIC IMPORTANCE

Some 87% of goods are imported in to the China by sea, hence shipping is economically vital.

PORT ACTIVITIES

China remains high growth with the higher-end growth years at 30-35% growth levels, and low-growth years closer to 15%. But the growth included also small facilities to the count and change the definitions for box movements.

China volumes always show higher growth than those forecasted and whether the expected growth will continue to at its present pace.

Certain parts of China may understate the true productivity potential of terminals, such as by overstating recent performance numbers that leads to over construction of facilities. Likewise, demand patterns in developed countries also play a key, underestimated, role in forecasting China and Asia terminal capacity and long-term demand patterns.

TOURISM

In 2004, 14% of people in China visited the seaside supporting the local economy.

TODAY IMPACTS

POLLUTION

Coasts and estuaries are the final recipient of pollution from both the sea and inland sources. River contamination frequently ends up on the coast, whether litter, chemical spills or nutrients released from farmland and wastewater treatment works. Similarly, oil spills in coastal waters and harbor areas will tend to be deposited on the coast.

Even low concentrations of polluting chemicals can have a significant effect since they are taken up by organisms such as plankton that form the basis of the entire marine food chain.

Litter from shipping, from inefficient handling of waste in shore-based facilities and from carelessly discarded rubbish can lead to significant quantities of windblown litter. This eventually accumulates on the sea bottom and on the shore causing odor nuisance, loss of amenity and impacting habitat quality.

An estimated of 20,000 tones of litter remains in China coastal area. Litter is also a significant nuisance to fishermen and can damage fishing nets.

CLIMATE CHANGE

The increased inland flooding which may be the result of climate change is increasing the sediment and nutrient transport to the coast, in with an associated increase nutrient loading of coastal waters and reduction in water quality. The resultant excessive algal growth starves the marine ecosystem of oxygen, causing fish death and impacting higher up the food chain.

Marine natural disasters have considerable impact along China’s coasts.

On average, the coast is affected by 2-5 strong storm surges per year. In one 1922 storm surge event, over 70,000 people died in Guangdong province. Economic losses exceeded 18 billion Yuan (or approximately $2.2 billion USD) as a result of an August 1994 typhoon landing in Wenzhou, Zhejiang province.