Our country is a large coastal country with 1With more than 80,000 kilometers of mainland coastline and about 3 million square kilometers of sea area under its jurisdiction, it is rich in marine resources and diverse in marine rights and interests.
The ocean is so important, let's get to know it.
We live on a blue planet, and the reason why it is blue is because the ocean area occupies more than 2 3 of the total area of the earth.
However, the oceans on Earth are collectively referred to as oceans, and oceans are oceans. How to divide the two?
It turns out that the waters of the sea can be divided into main and secondary parts. The main part is the ocean, and the subsidiary part is the marginal part of the ocean, which is called the sea, bay, and strait.
Let's talk about the ocean first: the area of the ocean is vast and the depth is large, generally above 2000 3000 meters; The salinity is 35% on average, with little annual variation, and is not affected by the mainland; High water color and transparency; There is a unique tidal system and a strong current system; The sediments of the ocean are calcareous soft mud, siliceous soft mud and red clay endemic to the deep sea.
Let's talk about the sea: the sea is small, accounting for only 11 of the total area of the ocean6%；The depth generally does not exceed 2000 3000 meters; Temperature is greatly influenced by the continent and has significant seasonal variations; The water color is low and the transparency is small; The sediments are mostly terrestrial organisms, such as sand, sediment, biological detritus, etc.
The sea is divided into the Mediterranean, the inland sea, and the marginal sea according to its location. The Mediterranean Sea, also known as the intercontinental sea, is located between continents and is large in size. Such as the Mediterranean Sea between Asia, Africa and Europe.
The inland sea, also known as the inland sea, is surrounded by a continent or continent and islands and archipelagos, and is small in size. Such as the Caribbean.
The marginal sea, also known as the continental margin sea, is the marginal part of the ocean, only some islands are separated from the ocean, and seawater can flow freely between the marginal sea and the ocean, such as the East China Sea.
The third said bay:
A part of the ocean or sea that juts out into the continent and its depth gradually decreases is called a bay.
At the entrance, the line between the cape and the cape serves as the dividing line of the bay. The nature of the water in the bay is generally similar to that of the adjacent water.
The maximum tidal range is often found in the bay, which is related to changes in the depth and width of the bay. For example, the tide of the Qiantang River in Hangzhou Bay in China is well-known in the world, and its tidal range can generally reach 6 8 meters, and the maximum can reach as much as 12 meters.
The fourth said the strait:
A waterway in the ocean with a narrow width between adjacent areas is called a strait. The main feature of the state of the sea in the strait is the jet current, especially the high speed of the current. The substrate is mostly bedrock and sand grains.
The currents in the strait generally flow from the upper and lower layers or flow out, such as the Strait of Gibraltar, and there are also flows in or out from the left and right sides, such as the Bohai Strait.