70% of the Earth's surface is surrounded by oceans, and 96% of the water on earth is sea water, so our Earth is an ocean planet. However, humans know very little about the ocean, no more than 5%. and humanity knows much the same thing about the universe. The average depth of the world ocean is about 3,680 meters, and the average height of the world's land is only 860 meters. Compared to land, the ocean is quite deep and quite wide. The deepest point in the ocean is the Mariana Trench, which is more than 11,000 meters deep, much higher than Mount Everest. Today I will show you what the deep sea world looks like.
It is between 3 and 30 meters underwater. The normal swimming depth of people does not exceed 3 meters underwater, it is mainly coral and aquatic reefs. plants grow.
40 meters underwater
This depth is generally the limit depth for “recreational diving”. If the diving depth exceeds 40 meters and continues to dive without strict training, joint pain, spasms, dizziness and other problems will occur, which is similar to "altitude sickness". Interesting, isn't it? This will happen the higher you go, and the same thing will happen the lower you go. The deepest swimming pool in the world is 40 meters. It is located at the Montegrotto Terme Hotel near Padua, Italy. It is a hotel specially designed for diving enthusiasts. Diving in this pool is very safe.
70 meters underwater
When diving to this depth, people will have hallucinations. The biggest fish in the world - — Whale. sharks generally live in this area.
100 meters underwater
This depth is the depth limit for professional divingional. At this depth, there is a kind of depth. live octopus. Called the giant North Pacific octopus, this octopus can change color like a chameleon, is 6 meters long and extremely large, so it was often considered a sea monster in ancient times.
130 meters underwater
This depth is the deepest in the world where “underwater weddings” took place. In 2014, a Japanese and an American, both professional divers, wanted to organize a wedding like everyone else. So they held a wedding 130 meters underwater in Thailand and even invited a priest to dive with them. Of course, the priest. is not an ordinary person, he is their part-time coach. After all, no priest is a professional diver, so he can just sit back and raise the price.
200 meters underwater
Below this depth, theLight is very weak and is not sufficient to produce photosynthesis. basically no green leafy plants below the depth. There is a fish called an oarfish that lives here. It is the longest bony fish in the world. Data shows that the adult oarfish.The hairtail fish can reach 11 meters in length and is known among the people as the "Dragon King of the Seas".
300 meters underwater
There is a kind of big crab living 300 meters away. Its scientific name is Giant Crab. The chelicerate crab has extremely long legs that can reach 4.2 meters when extended. He has a very small head but a very fierce temperament. It is called a killer crab and its meat is very delicious.
The depth to which humans can dive using oxygen tanks and other equipment can reach 332 meters, which is a world record set par an Egyptian.
In 2014, he dived up to 332 meters in 15 minutes using an oxygen tank. He wanted to continue diving, but since he lost consciousness after diving to this depth, he had no choice but to dive. Interestingly, it took him 13 and a half hours to come to the surface. Why was it so slow? Because the oxygen tank contains not only oxygen, but also nitrogen, carbon dioxide and other gases. When he inhales these gases in the water, they are all squeezed into his bloodstream. Under this pressure, there are no bubbles, but when speed floats. exceeds If it is too fast, the bubbles in the blood will expand quickly, and the human body will not be able to resist the explosion, so it must float slowly. Allow your body to slowly adapt to the changes.
Submarines generally operate between 300 and 500 meters underwater.
500meters underwater
This depth is no longer a human world, it is a world of animals, blue like the largest animal in the world, the whale can dive to a maximum depth of 500 meters. Its roar is extremely loud, reaching 188 decibels, which is louder than a fighter jet, and its sound can travel 1,600 kilometers.
In addition to blue whales, there is a kind of penguin that can easily dive to this depth, it is called the emperor penguin, and it can swim here for 10 minutes very. carelessly. It is the bird most resistant to stress.
600 meters underwater
There is a kind of fish called anus with large fins, and its head is transparent. There are two balls inside. These two balls are eyes. The eyes look up and can't look forward, so he doesn't need to look down at all. Once this type of poisson is caught, he will explode.
700 meters underwater
At this depth, European eels live, and eel rice that everyone loves to eat is made It is. Some think she lives in the river. In fact, the eel lives half of its time in the sea. When it spawns, it returns to the river and is eaten by humans.
900 meters underwater
The king squid lives here. It is more than ten meters long and its eyes are also large. like those of an adult. The human brain is so big that it is possible for everyone to do it. I think the king squid is very rare and rarely seen, but in fact there should be a lot of them. It's just that we rarely go to such deep places and see very little. Why do we feel like there are so many? Let's continue to see.
1000 meters underwater
This depth hasdyes the semi-deep sea area. There is no light at all in this area. It's completely dark, there are fewer animals living in this area, and most of the animals are glowing.
1,300 meters underwater
One of the largest sea turtles, called the leatherback turtle, lives here. this type of turtle has a soft shell, and it will also go to the beach to lay eggs, and then return to the water at 1,300 meters.
There is also a very scary shark that lives in this area. It's called the European sharpnose shark, also known as the goblin shark. The biggest feature is that its mouth and jaws are separated. When it eats, the teeth inside fly out to bite the prey, then retract it.
1,700 meters underwater
There is a cute thing that lives in this area, and it will come back also on earth. This is the southern elephant seal, which is the largestande species among seals. Its trunk is particularly large. An adult southern elephant seal can weigh up to 5 tonnes and its body length can reach 7 meters.
2000 meters underwater
At this depth, there is a fish called the black dragon fish. This fish looks a bit. scary. , like an alien creature, with a mouth full of sharp, black teeth. There is a beard under his mouth, and there is a light bulb-like thing under the beard that emits light. prey.
3000 meters underwater
Below 3000 meters you enter the deep water zone. The water temperature at this depth is only. 1 to 2 degrees. There is no light and the water pressure is as low as over 300 atmospheres. There are very few fish at this depth, but there is a very large creature which is the sperm whale. can dive up to 3,000 meters. Among thes whales, there is no dive deeper than this. Even deeper, she really likes to eat giant squid. The entire body of the giant squid is soft, only the mouth is hard. the stomach of the sperm whale and gradually forms a thick, dark substance in its small intestine, which appears in the form of lumps. And this substance is the world famous "ambergris", which is why it is called sperm whale. Then it is judged by dissecting the sperm whales that sperm whales around the world eat around 5 million king squid every year. How many king squid must there be under the sea?
3800 meters underwater
There is a ship parked at this depth, "Titanic", Titanic in 1912 The number and Jack sank at this depthWell, over 100 years have passed since this ship was saved. In addition, it has been registered as an "underwater cultural heritage" in the world, and rescue is no longers allowed if you probably won't be able to visit it. you want.
4000 meters underwater
There is a kind of fish called "viper fish" that lives at this place, and it looks very scary. The teeth are very long. Generally, fish living in the deep sea have relatively little food, so once they have bitten their prey, they should not let it escape.
6,000 meters underwater
This depth has entered the "ultra deep sea zone". There is a submarine in Japan. called "Deep Sea 6500" dived to a depth of 6,500 meters in 1989. Later, in 2012, the Chinese submarine "Jiaolong" dived to a depth of 7,000 meters.
8,100 meters underwater
This depth is the deepest place where fish live In 2017, a Chinese A. One. deep-sea exploration team discovered a white fish at more than 8,150 mbeings. Then, in the same year, a Japanese team also discovered the same fish there. This type of fish is called “Mariana snail fish”. It is not yet known whether there are fish in the deeper areas.
10,000 meters underwater
A huge single-celled protist was discovered here, with a body as long as 20 centimeters, it has only one cell and it is a very, very primitive creature. So, in very primitive times, single-celled organisms could have been this large.
The deepest place in the ocean is located in the Mariana Trench. The deepest place is called Challenger Deep. The depth of this place is 11,034 meters. This depth cannot be measured with it. Sonar. It was analyzed by the sound waves produced by the bombs. So far, four people have reached this depth in 1960. One was called "Donald Walsh" eand the other “Jacques”. . When they arrived, they discovered that there were flounder, as well as some shrimp. The second time he dove to this depth was Cameron in 2012. He is said to have seen shrimp-like things about 3 centimeters long, and nothing else. He said the seabed was as barren as the surface of the moon.
The last person to reach this depth was in April and May 2019. He dove twice in a row. It is an American underwater explorer named "Vic" Do Vescovo". 10,928 meters. It is said that he saw nothing at the bottom of the sea, only a pile of garbage bags. If we go back in exploration in the future, it will probably not be so simple
1. Jellyfish
Jellyfish is a very beautiful animal. aquatic with a transparent umbrella-shaped body Although it does not have a spine, its body is very large and it mainly depends one the buoyancy of water to support its enormous body. In the blue ocean, these jellyfish swimming in different colors are very beautiful.
However, these beautiful creatures are also deadly “killers”. A jellyfish sting can cause a rash, making the skin itchy and very painful. Although most jellyfish are non-lethal jellyfish, box jellyfish are deadly. Their tentacles have venom-filled stings that can stop the heartbeat of their prey. If you suspect box jellyfish on your beach, it's best not to go in the water or take precautions to stay away from them, even those that wash up on shore . If you are accidentally bitten by this almost invisible animal, be sure to seek medical attention as soon as possible.
2. Stingray
The stingray is like a fish holding a sword, a guerrier ready to fight back. This flatfish has a long, whip-shaped tail with barbs sharp enough to pierce hard surfaces. Usually, stingrays avoid crowded places, but they often hide in sand caves. Once they are riding waves in shallow water and you accidentally step on them, the sharp barbs on their tails immediately pierce your skin, causing severe reactions.
In general, its toxins are not fatal, but the reactions caused by the toxins can be life-threatening, so we must be careful. To avoid stepping on a stingray, it is best not to walk in shallow water but to drag yourself along the sand. Rather than lifting your feet with each step, drag them with your feet buried in the sand so that the sand. stingrays.
3. The sea urchin
The sea urchin ist delicious, but it's not a cute animal. In fact, sea urchin mortality cannot be underestimated. They move in shallow water and will deal you a heavy blow if you step on them. Sea urchin spines are very sharp and contain toxins that can cause painful reactions in the human body. Even if there is no risk to life, it is better to be careful. Once a sea urchin's spine breaks in your skin, you should seek professional help to remove the spine, otherwise it will burrow into the deeper tissues of your body.
4. Stonefish
Stonefish are the camouflage experts of the animal kingdom and are extremely venomous. Once it senses danger, the spines on the stonefish's back straighten and release venom. People who have been stung by stonefish spines are often reported to asknt have their infected parts amputated because the intense pain is unbearable. It is difficult to avoid stonefish because they are very good at blending into their surroundings.
Stonefish are found in coastal areas of the Indo-Pacific and parts of the Caribbean and Florida. Although there are few reports of people being stung by stonefish, people swimming in these waters should still be careful. To avoid getting stung by stonefish, never go barefoot and wade in the sea. If you are stung, apply warm water to the wound to ease the pain until you get medical help.
5. Sharks
Sharks are known to be dangerous. You may not encounter sharks in the sea often, but you should still have some knowledge about sharks, just in case.
First of all, don't play in shark-infested waters, as this will attract sharks.
Second, if you encounter a shark, don't provoke it. It is best to swim as gently as possible.
Third, pay attention to other marine life nearby. If they behave abnormally, it means there may be a shark nearby.
In short, when swimming in the sea, you must understand the environment around you and understand this knowledge so as not to panic when encountering a shark and avoid unnecessary risks.
6. Algae
Although the danger of microalgae is not great, care must be taken. Harmful algae blooms, often brightly colored, are called “red tides.” They produce toxins and cause illness in humans. Nowadays, “red tide” appears in lakes and oceans around the world, thiswhich has become a very serious problem. Harmful algal blooms can irritate the eyes and nose, cause stomach problems or more serious neurological reactions. Therefore, before swimming, you should know the water quality of the sea area.
(Authors: Liu Yadan, chief science communication expert of the Chinese Fisheries Society, Li Shengfa, director of the resource office of the East China Sea Fisheries Research Institute of Chinese Academy of Fisheries Sciences, original article, please do not reproduce without permission)