Rice and wheat can't grow in the ocean, but fish and shellfish in the ocean can provide delicious and nutritious protein food for human beings.

Experts optimistically pointed out that the ocean granary has great potential. The annual output per hectare of land crops with the highest yield in 20 14 is only 0.75438+0 tons in protein. However, scientific experiments show that the maximum output of mariculture in the same area can reach 27.8 tons, and the commercially competitive output is 16.7 tons.

2. Freshwater resources

It has become a fixed trend to ask for fresh water from the ocean. In the Middle East where fresh water resources are scarce, seawater desalination was regarded as an effective way to obtain fresh water resources decades ago. The United States is actively building desalination plants to meet people's demand for fresh water now and in the future.

There are nearly 8,000 desalination plants in the world, which produce more than 6 billion cubic meters of fresh water every day. Russian oceanographers have found that there are also abundant fresh water resources at the bottom of the world's oceans, accounting for about 20% of the total seawater. This shows a bright future for mankind to solve the freshwater crisis.

3. Oil

At present, oil occupies the first place in energy. However, because some large oil fields on land are relatively easy to exploit, some have been exhausted and some are on the verge of exhaustion. In the past two or three decades, many countries in the world have been vigorously developing offshore oil industry. The exploration results show that the world oil resources reserves are 654.38+000 billion tons, and the recoverable amount is about 300 billion tons, of which the seabed reserves are 654.38+03 billion tons.

4. Rare manganese nodules-manganese nodules

Rare manganese nodules-Manganese nodules are a kind of rare metal ore source on the seabed. It was first discovered in the Atlantic Ocean by a British marine survey ship in 1873. However, the formal and organized survey of manganese nodules in the world began with 1958.

Investigation shows that manganese nodules are widely distributed at the bottom of the deep sea from 4000 to 5000 meters. It is the largest metal mineral resource in the future. Interestingly, manganese nodules are a regenerative mineral. It grows at a rate of about100000 tons every year, and it is an inexhaustible mineral.

5. submarine hydrothermal deposits

In the mid-1960s, American marine survey vessels first discovered deep-sea hydrothermal deposits in the Red Sea. Then, some countries found more than 30 such mineral deposits in other oceans. Hydrothermal deposits, also known as "heavy metal mud", are high-temperature lava ejected from cracks in sea ridges (seamounts).

Washed, deposited and piled up by seawater, it can grow as fast as plants at a rate of several centimeters per week. It contains dozens of rare and precious metals such as gold, copper and zinc, and the grade of gold and zinc is very high, so it is also called "submarine gold and silver warehouse".

Refer to the above? Baidu encyclopedia-ocean