1.2Blue ocean, the origin of life
Life originated from the ocean.
Seen from space, the earth is a beautiful blue planet and that blueness is the ocean. China has an ocean area of nearly 3 million square kilometers. In the process of constructing a beautiful China, therefore, great importance is naturally attached to marine ecology. So what is China’s marine ecosystem like?
1.2.1 Bohai Sea
The Bohai Sea is an inland sea burrowing its way into the Chinese mainland with an area of about 80,000 square kilometers. It is rich in animal and plant species, with a great biomass of meretrix, ostrea plicatula and penaeus chinensis. As a result, it has become an excellent fishing ground.
1.2.2 Yellow Sea
The Yellow Sea is a semi-enclosed sea with an area of 380,000 square kilometers lying in the North Temperate Zone. The Biotic population from the frigid zone, the subpolar zone, the tropics, and subtropics, together with local biotic population, form a unique marine biota.
1.2.3 East China Sea
With an area of about 770,000 square kilometers, the East China Sea embraces the most numerous islands in China. With flat seabed and high biomass, it offers many good fishing grounds rich in Larimichthys crocea, L. polyactis, hairtail and cuttlefish, etc. The fishing grounds around the Zhoushan Archipelago are called the treasure house of Chinese marine fish.
1.2.4 South China Sea
The South China Sea is China’s largest sea, covering an area of 3.5 million square kilometers. In addition to the continental shelf area, it prides itself on deep-sea area accounting for 30% of the entire sea with an average depth of 1,400 meters. The South China Sea abounds in geographical conditions and varied biological types. Because of its tropical climate, it is suitable for the propagation of coral, so coral fish and tropical oceanic fish are plentiful there. However, one special feature of the ecosystem is that there is no dominant fish species.
Although humans do not live in the ocean, it provides abundant food for them. It is a good source for exploitation of nutrients. In addition, the ocean is a vital means of transportation, making it a preferred choice for bulk cargo transportation. On the seabed and in the continental shelf area are found large deposits of energy sources such as oil and flammable ice (also known as methane ice).
More importantly, the ocean is a source of water. Through evaporation, water is transmitted to terrestrial ecosystems in the form of vapor while retaining minerals and pollutants from human activities. Therefore, the ocean also has the function of metabolizing waste from economic activities. Although the capacity of accommodation of the marine environment is enormous, inappropriate economic activities have already resulted in marine pollution. If one day the ocean ecology can no longer metabolize waste efficiently, then the earth will be in jeopardy.
5 The Bohai Sea has recorded over 120 kinds of phytoplankton, over 100 kinds of zooplankton, over 100 kinds of phytobenthos, and over 140 kinds of zoobenthos. Besides, there are more than 120 kinds of nekton, mainly fish, as well as shrimp, crabs, cephalopods and marine mammals.
6 The Yellow Sea has recorded 368 kinds of phytoplankton, 130 kinds of zooplankton, over 200 kinds of Zoobenthos. In the north, 219 kinds of Nekton have been discovered, and in the south, 225 kinds, including 15 kinds of whales, 3 kinds of pinniped and 4 kinds of turtle.
7 The South China Sea Coastal Current and the kuroshio are the two main ocean currents of warm shallow waters of the East China Sea. Phytoplankton species near the Yangtze River Estuary amount to 64, with 261 near the coastal waters of Zhejiang. Zooplankton species near the Yangtze River Estuary total 81, with 223 near the coastal waters of Zhejiang. Benthos so far recorded reach 342 kinds. Nekton species near the Yangtze River Estuary and the nearby shallow watersas well as in Zhejiang shallow waters are as numerous as 167 and 203 respectively.
 Phytoplankton in various coastal areas around the South China Sea varies from 104 to 260 species while Zooplankton species amount to 380. Benthos species and cephalopoda species are 2,861 and 58 respectively, among which the common species of economic value is 25.
本书由北京语言大学出版社，2014（教学课件光盘版） 作者 蒋高明