Urgent need! ! ! ! ! About the ocean! !

Development and utilization of marine resources and marine environment

Types of marine resources

There are abundant resources in the ocean. Nowadays, the contradiction between the shortage of global food, resources and energy supply and the rapid population growth is increasingly prominent, so it is an inevitable trend of historical development to develop and utilize the rich resources in the ocean. At present, the marine resources developed and utilized by human beings mainly include marine chemical resources, marine biological resources, seabed mineral resources and marine energy.

seawater can be directly used as an industrial cooling water source and an inexhaustible desalination water source. Developing seawater desalination technology and asking for fresh water from the ocean is one of the important ways to solve the problem of insufficient fresh water in the world.

more than 8 chemical elements have been found in seawater. At present, the development of marine chemical resources has reached industrial scale with salt, magnesium, bromine and fresh water. With the development of science and technology, rich marine chemical resources will benefit mankind widely.

There are more than 2, kinds of living things in the ocean, including 18, kinds of animals, including more than 16, kinds of fish. In ancient times, humans began to catch and collect seafood. Now, human marine fishing activities have expanded from offshore to various sea areas in the world. The improvement of fishing gear, fishing boat and fish exploration technology has greatly improved the marine fishing ability of human beings. Marine biological resources, which are composed of fish, shrimp, shellfish and algae, can be used continuously through cultivation and proliferation, in addition to being directly fished for food and medicine.

There are abundant petroleum, natural gas, coal, sulfur, phosphorus and other mineral resources buried in the shallow seabed of the continental shelf. The coastal sand mines in the nearshore zone are rich in building materials and metal minerals such as sand and shells. Deep-sea manganese nodules are widely distributed in most ocean basins, which are the most potential metal mineral resources that can be utilized in the future (Figure 3.14 "Deep-sea Manganese Nodules").

There is huge energy in seawater movement, which belongs to renewable energy and has no pollution. However, these energy densities are very small, and to develop and utilize them, special energy conversion devices must be adopted. At present, tidal power generation and wave power generation are of commercial development value, but the project investment is large and the benefit is not high.

marine fishery production

marine fishery resources are mainly concentrated in the coastal continental shelf, that is, the part of the continental seabed extending from the coast to about 2 meters underwater. Here, the sunlight is concentrated, the biological photosynthesis is strong, and the rivers entering the sea bring rich nutrients, so plankton flourishes (Figure 3.15 "Outline of Continental Shelf"). These plankton are the bait of fish, and their distribution in the ocean is very uneven, generally more in temperate sea areas.

The seasonal changes in temperate regions are remarkable. When surface seawater and bottom seawater exchange in winter, the flooded bottom seawater is rich in nutrients, which come from decaying biological remains in the ocean. At the junction of warm current and cold current or where there is cold seawater flooding, the bait is rich. These places are usually the locations of fishing grounds (Figure 3.16 Distribution of Major Fishing Areas in the World). Therefore, although the continental shelf waters only account for 7.5% of the total ocean area, the catch accounts for more than 9% of the total ocean catch in the world.

The major fishing countries in the world are located in temperate regions, where the consumption of fish products is high and the market demand is large. China and Japan are countries with more marine catches in the world. China has made full use of offshore fishing grounds (Figure 3.17 "shenjiamen Fishing Port in Zhoushan Fishing Ground") and shallow beaches to develop marine fishing and seawater aquaculture, and at the same time, offshore fishing has also achieved great development. Japan has limited arable land and high population density, so marine products account for a large proportion in the food structure.

offshore oil and gas development

the development of submarine oil and gas began in the early 2th century. Its development has gone through the process from offshore to offshore, and from shallow sea to deep sea. Limited by technical conditions, only oil and gas deposits extending directly from the coast to the shallow sea can be mined at first. Since the 198s, stimulated by the energy crisis and technological progress, offshore oil exploration and development have developed rapidly, and offshore oil development has rapidly advanced to the continental shelf, gradually forming a brand-new offshore oil industry sector.

geologists and geophysicists usually use seismic wave method to find submarine oil and gas deposits, and then estimate the type and distribution of the deposits through offshore drilling, and analyze whether it has commercial development value.

offshore drilling platform (figure 3.18 "offshore drilling platform") is the working base for the exploration and exploitation of submarine oil and gas, which marks the level of submarine oil and gas development technology. The transportation of staff and materials between the platform and the land is generally completed by helicopter. Oil and gas fields are generally far away from refineries, and oil and gas should be transported to their destinations by ships through oil loading stations or directly to the coast by submarine pipelines.

The exploration and exploitation of submarine oil and gas is a project with high investment, high technical difficulty and high risk, and international cooperation and project bidding are one of the feasible ways.

utilization of marine space

With the rapid growth of the world population, the land space is becoming more and more crowded, and the development and utilization of marine space is attracting more and more attention. The available space of the ocean includes three parts: the sea, the middle of the sea and the bottom of the sea. With the gradual advance of human beings to the ocean, the ocean will become a vast space for human activities (Figure 3.19 Schematic diagram of the future utilization of ocean space).

The marine environment is different from the land, and its environmental and ecological conditions are complicated and special. Human activities are near the sea and on the surface of the ocean, so it is necessary to resist the changeable meteorological conditions of the ocean and the movement of seawater; Deep-sea activities should be able to adapt to the dark, high pressure, low temperature and anoxic environment; Seawater is corrosive and sea ice is destructive, so there are strict requirements for materials and structures of engineering equipment. Therefore, the development of marine space resources is highly dependent on science and technology and capital investment, with high technical difficulty and high risk.

the utilization of marine space has expanded from traditional transportation to many fields such as production, communication, power transmission, storage, culture and entertainment. Transportation includes seaports, ships, navigation canals, undersea tunnels, bridges, airports and pipelines. The production space includes offshore power station, industrial artificial island, offshore oil city, land reclamation, marine pasture and so on. Communication and power transmission space is mainly submarine cables. In terms of storage space, there are submarine freight yards, submarine warehouses, offshore oil depots, and marine waste disposal sites. The space of cultural and entertainment facilities includes marine parks, bathing beaches and marine sports areas.

ocean transportation and port construction

the ocean used to be a natural barrier for human beings to engage in transportation. For a long time, mankind has been trying to turn the marine barrier into a smooth road at sea. At first, people used manpower, wind or ocean currents as power to drive wooden boats in the offshore areas. With the arrival of Europeans on the American continent, the world's ocean shipping has changed from offshore to ocean. After that, important waterways of the world's oceans were opened one after another. At the beginning of the 2th century, the navigation channels to the South Pole and the North Pole were opened, and the Panama Canal and Suez Canal were opened one after another. Now, human beings have been able to sail ships to any sea area in the world (Figure 3.2: Main shipping routes in the world).

in 196s, the world oil production and transportation increased, and large oil tankers were developed. The rise of container ships has brought about a revolution in marine cargo transportation. Today, million-ton container ships and giant oil tankers shuttle across the vast ocean. These ships not only have modern instruments and equipment such as radio navigation and global positioning technology, but also can choose the best route service to save energy and navigation time and reduce danger.

Coastal ports are places where marine transport ships berth, transit and load and unload goods, and also the main places for people to develop and utilize marine space. Generally, a port has a service area, that is, the hinterland, through which goods and goods in this area spread outward. In order to complete the transportation task, the port should have supporting facilities, such as docks, loading and unloading equipment, and efficient operation services. In the process of port development, affected by internal and external factors, the scale, service function and scope of the port may change. For example, in order to attract ships to transit in their ports, the governments of some countries have implemented special policies to turn ports into free trade zones and free ports with little or no payment.

Rotterdam in the Netherlands has long been the center of world trade. After that, the port of Rotterdam continued to develop by digging a canal connecting the North Sea and improving the water transport conditions. Rotterdam has developed agriculture, mineral products processing industry and shipbuilding industry by using the function of transferring bulk goods (Figure 3.21 Land use of Rotterdam Port). Relay trade also promoted the rapid development of modern industry in the hinterland. After World War II, the economies of western European countries revived, Rotterdam became the gateway to the European Union, the harbor and aviation facilities were improved, and the port's transit function became more prominent. Now, Rotterdam is one of the largest ports in the world, and its hinterland covers half of the countries in the European Union.

Reclaiming land from the sea

The contradiction between people and land in coastal areas has intensified, making people look to the sea. The Dutch began to reclaim land from the sea in the 13th century. At present, one-fifth of the land in the Netherlands is enclosed from the sea. Reclaiming land from the sea is an important way to alleviate the contradiction between population and land shortage, but it needs full scientific demonstration, especially the supporting construction centered on water conservancy projects.

The newly-built land is called an artificial island, which is built with sand, gravel, mud and waste materials in the offshore shallow waters and connected with the coast through seawalls, trestles or subsea tunnels. Some developed coastal countries in the world, such as Japan, the United States, France and the Netherlands, have built artificial islands. Among them, the maritime city (figure 3.22 artificial island in Kobe, Japan) has the largest scale and the most complete functions. The construction of a maritime city requires huge projects and costs, and needs to be based on strong national strength.

Macao has a large population and little land, and the limited land is not enough to meet the needs of residential development, greening, transportation, industry and commerce. There are many shoals along the coast of Macao, some of which can be exposed to the water at low tide, and Macao people regard them as good reserve land resources. Over the past 1 years, Macao people have doubled their land area by land reclamation (Table 3.2 Changes of land area in Macao over the years and Figure 3.23 Scope of land reclamation in Macao over the years).

marine environmental protection

marine environmental problems include two aspects: first, marine pollution, that is, pollutants enter the ocean and exceed the self-purification capacity of the ocean; The second is the destruction of marine ecology, that is, under the influence of various human and natural factors, the marine ecological environment is destroyed.

(1) marine pollution

most of the marine pollutants are produced on land. Coastal activities, such as waste dumping and port engineering construction, also discharge pollutants into coastal waters. Pollutants enter the ocean, polluting the marine environment, endangering marine life and even endangering human health.

The wastes discharged from industrial production are the main sources of marine pollutants, which are concentrated near large ports and industrial cities. From 1953 to 197, the mercury pollution incident occurred in Minamata Bay, Kyushu Island, Japan, because the factory discharged mercury-containing waste in the process of producing organic products. These harmful substances are gradually enriched in fish and shellfish after flowing into the ocean. In the end, more than 1 people were seriously poisoned and died successively.

The cooling water discharged from nuclear power plants and factories has a high water temperature, which often affects marine life when it flows into estuaries or the sea. Pesticides applied to farmland flow into rivers with rainwater, or deposit near estuaries with soil particles, and finally enter the ocean. Occasional accidents of offshore oil platforms and tankers cause oil leakage and overflow, resulting in marine pollution.

(II) Destruction of marine ecology

In addition to marine pollution, human production activities, such as engineering construction and fishery (reclamation and overfishing, etc.), and changes in the natural environment, such as global warming and sea level rise, will destroy and change the marine ecological environment. Over-fishing of some marine organisms by human beings has led to a decrease in the quantity and quality of marine biological resources, and some species are on the verge of extinction. Some coastal engineering construction and reclamation lack scientific demonstration, which destroys the coastal environment and coastal ecosystem. At present, marine development activities still lack comprehensive and long-term planning, and the comprehensive benefits are relatively poor.

Oil pollution and monitoring and prevention

Ships in coastal industrial production and shipping routes are the main sources of oil pollution. Therefore, oil-polluted areas are concentrated in coastal waters and along sea lanes. Oil spill caused by accidents has attracted much public attention because of obvious pollution signs, concentrated pollutants and serious harm, and is also the focus of pollution control at present.

in order to reduce the occurrence of accidents, many countries are experimenting with new crude oil loading methods. Some countries are equipped with decontamination vessels to remove garbage and dirty oil from the port surface.

maritime rights and interests and the United Nations Convention on the Law of the Sea

Since the 196s, there has been a worldwide upsurge of ocean exploitation. The rapid development of marine science and technology has become one of the important fields of contemporary new technological revolution. In order to adapt to the new situation of international ocean development, protection and management, after more than 2 years of efforts, the international community adopted the United Nations Convention on the Law of the Sea, which came into effect on November 16, 1994. The birth of the Convention on the Law of the Sea has brought about great changes in the international maritime legal system. For example, the long-standing dispute over the breadth of the territorial sea has been resolved; The international seabed and its resources have been established as the common heritage of mankind.

according to the United nations convention on the law of the sea, 144 coastal countries in the world have the territorial sea right of 12 nautical miles, and the sea area under their jurisdiction can extend to 2 nautical miles. As their exclusive economic zones, they have the sovereignty to explore, develop, utilize, protect and manage the natural resources on the seabed and the subsoil. The sea area under the jurisdiction of China is 4.73 million square kilometers, which is about half of China's land area. Therefore, it is increasingly important to strengthen comprehensive marine management.

The birth of the United Nations Convention on the Law of the Sea has taken an important step towards establishing a new international legal order. However, because the United Nations Convention on the Law of the Sea has to take into account the interests and requirements of various countries, there are still many imperfections and ambiguities. Therefore, in the process of implementation, some new contradictions and problems will inevitably arise. For example, in closed and semi-closed sea areas, the 2-nautical-mile exclusive economic zone advocated by neighboring countries may overlap, and there are also some issues such as island sovereignty disputes and fishery resource allocation, which may become new factors of tension between neighboring countries and even trigger international conflicts. Therefore, the delimitation of maritime areas and maritime rights and interests under the jurisdiction of neighboring countries require the countries concerned to settle them fairly and reasonably in the spirit of friendly consultation.

overview of seawater chemical resources

Marine chemical resources refer to various chemical elements contained in seawater that can be used by human beings. The composition of seawater is very complicated. The global ocean contains 5 million tons of salt and a lot of very rare elements, such as 5 million tons of gold and 4.2 billion tons of uranium, so the ocean is the largest mineral resource pool on the earth. The sustainable utilization of marine resources is an important prerequisite for human survival and development. At present, the world extracts more than 2 billion tons of fresh water, 5 million tons of salt, 2.6 million tons of magnesium and magnesium oxide and 2, tons of bromine from the ocean every year, with a total output value of more than 6 million US dollars. Water is the source of life, and there are more and more water-deficient areas in the world. Seawater desalination has become an important way to obtain fresh water resources, all of which are to be studied in marine chemistry.

marine living resources

1. Estimation of marine living resources. The ocean is a treasure house of biological resources. According to the statistics of biologists,