Underwater weeds write a composition.

1. Interesting marine fish composition [Interesting marine fish composition] Interesting marine fish classmates, what kind of fish do you like in the ocean? I'm telling you, I like it ten thousand times. On this autumn outing, we went to the underwater world that I had long wanted to go to. At the same time, I have seen and learned many rare marine fish in my daily life. First of all, let's take a look at the colorful angelfish that everyone loves. Colorful angelfish is a kind of very docile fish, and it has the reputation of king of tropical fish, so students compete to watch it on the day of autumn outing. They are in droves. Looking through the glass, they are a wonderful and interesting composition of marine fish. Then, we saw the lively and rough temperament, and there was a name that sounded like a tiger head. Big pencil fish has the habit of eating aquatic plants. And its sharp mouth seems to be holding a big pencil. Although not many people visit them, in my heart, the big pencil fish is a very interesting fish. I have seen so many fish. However, my favorite is "Ali" with a strange name. Speaking of Ali, I don't think everyone is familiar with it. Ali's whole body is very small, only 7-8 cm short, only 10- 12 cm long. I can't get enough of it. Ali is mostly light blue with two little red dot eyes. But most importantly, if you want to be close to the lovely Ali, you can gently stick your face on the glass wall. Although separated by a layer of glass, maybe Ali will kiss your face! It can be seen that Ali is a very hospitable fish. In the fifth grade of primary school, he wrote "Interesting Composition of Marine Fish". There are many magical fish in the underwater world. I hope that one day, you can also visit and watch those interesting and fun marine fish ... after listening to so many fish, my mouth is almost dry. Well, the fish will say goodbye to us! I hope you can come and see these lovely fish sometime. Interesting marine fish composition 550 words for primary school students (/).

2. Write a composition with streams, stones and water plants.

A stone bounced off the mountain and fell into the stream, blocking the path of the stream. Natural edges and corners, like sharp steel knives, protect the body and are inviolable.

The stream is singing, from far to near.

The stone said, "Dude, you'd better make a detour, or I'll chop you up."

Xiaoxi said: "My way forward will not change, I would rather be crushed!" " "Say that finish, made her way forward. The partners behind are like hordes, moving forward wave after wave.

I don't know how long it took, but the sharp edges and corners of the stone became bare and the proud body became smaller. The stream is still singing and gurgling forward. ...

With the progress of science and technology and the development of the times, a new era of developing the ocean has arrived. In the process of developing the ocean, people will get more wealth from the ocean more effectively. More and more countries are planning to establish or have established undersea pastoral areas and undersea pastures, and people are gradually transitioning from the era of simple marine fishing in the past to the era of "cultivating the sea" in the future. In the near future, people will work better and more effectively in undersea pastoral and undersea pasture than on land, because the output of marine culture is 100 times higher than that of land farming in the same area. People will breed a large number of seaweed and seaweed as feed for cattle, pigs and sheep on land to obtain more protein, and the total output of underwater pastoral areas in the world will soon jump from the current 20 million tons to 50 million tons. A large number of seaweed and seaweed will also be harvested by underwater combine harvesters and then hoisted to the ship by steel cables.

In the near future, the fishing nets used by people for generations will be replaced by powerful water absorption devices. Using the light emitted by electric field, sound with certain frequency and special compounds dissolved in water, fish can be lured and forced to gather together and swim close to the suction pipe laid down on board, and the suction pipe will be sucked into the cabin together with the fish carrying water. By that time, people will get more than 654.38 billion tons of seafood from the ocean, ten times or even dozens of times more than what they get from the ocean now.

With the increasing demand for oil, natural gas and other resources in the world and the massive exploitation of these resources, these resources on land will be exhausted day by day. People will inevitably look to the ocean or look for new energy sources. It is estimated that the seabed oil reserves are about 90 billion tons, and the oil reserves in the Arctic Ocean alone can be used by the world for 50 years. At present, more than 100 countries and regions have explored and developed continental shelf and deep-sea oil, and more than 500 oil and gas fields have been discovered. The implementation of a ten-year world offshore drilling plan is coming to an end. Explore and develop submarine oil and build a production base on the seabed. For the transportation problem after submarine oil exploitation, people will use large submarines. Imagine sinking a huge plastic cylinder into the bottom of the sea, which is filled with 654.38+10,000 tons of crude oil and towed by a submarine. Some people also designed to transport it by spaceship.

There is a huge amount of energy in the ocean, which is called the "blue ocean of coal" and will be transformed into the future energy of mankind. In the future, the marine thermal energy conversion plant will be located in the sea, and electricity can be supplied to cities through coastal cables. The content of heavy water in seawater called "future fuel" is much higher than that in land water. Hydrogen isotope can be extracted from heavy water, and scientists are using it for thermonuclear reaction experiments. If successful, it will become an inexhaustible source of energy.

In the near future, people will also build "underwater cities", which is not an illusion, but a reality. At present, Japan has built a "small city" for Arab countries to swim at sea. Most of it is made of steel, and the center is a six-story building. There is a small indoor garden, a cinema, and all the water and electricity are self-provided. Can meet the needs of cultural and recreational life of offshore oil production workers. The floating city is supported by eight tall pillars. Put them away and you can sail like a boat. In the future, many offshore factories will be built in the sea near raw material production sites or markets to provide materials for urban residents at sea. In Longchuan Bay, southwest of Shikoku Island, Japan, there is a "park in the sea". People can enjoy the wonders of the seabed through the 60 cm diameter 16 glass window: grotesque rocks, colorful corals, all kinds of strange fish, strange starfish and anemones. Since the first underwater laboratory was built in the United States, many countries have followed suit and built "steel houses" and other buildings on the seabed. The air pressure in the "house" is the same as the sea surface, and people can work normally in it, repair oil and gas wells on the seabed, salvage sunken ships, explore the seabed or replenish submarines. It is also reported that a group of Japanese engineers and architects. It is planned to build the world's first "marine city" in the sea area from Tokyo 120km to solve the human settlement problem in the future. Ocean City will be built on the seabed 200 meters deep, with a four-story steel platform, about 70 meters away from the sea surface, covering an area of 23 square kilometers. The whole city will be supported by 65,438+00,000 solid columns, and induction devices will be installed near the columns. We can measure typhoons, tsunamis and undercurrents, adjust ourselves to resist these external pressures and maintain the stability of Ocean City. In addition to residential areas, Ocean City also has a commercial center, 400 tennis courts, 8 golf courses, 2 baseball fields, 1 artificial fields for growing fruits and vegetables, and roads connecting vertically and horizontally. The construction cost of Ocean City is estimated to be 200 billion dollars, and this huge project is expected to be completed by the end of this century. By 2 1 century, this "undersea city" will be inhabited by more than 1 10,000 people. At that time, the deep seabed will no longer be silent, and it will become as lively as the mainland. More and more people will explore it, build it and paint this grand blueprint with their own wisdom and hands.

The future of the ocean shows people brilliant prospects, and the vast ocean will make great contributions to mankind.

4. Write a science fiction composition of about 500 words according to the seabed (Band 6). In the future, there will be a second home for mankind on the earth-an underwater city that makes full use of marine resources.

In order to resist the great pressure of seawater, this underwater world was built in a huge coral colony. Through a long corridor, you can enter this huge coral community. Many huge round water polo balls have been built here. This is a house where human beings live. Humans immigrated here from land.

The climate in the underwater world is very similar to that on land. You must ask, how can you live without sunshine and water on the seabed? You don't have to worry, there are two huge machines in the deepest part of the underwater world, one is the sunlight processor and the other is the well-known seawater desalination device. This solar processor is directly connected to the ground, absorbs the sunlight from the ground, and then transmits it to the solar cell at the bottom of each water polo through the pipeline, and then converts it into electric energy and transmits it to the energy lamp at the top of the water polo. The seawater desalinator directly absorbs seawater, desalinates seawater, and then sends it to the water polo.

Underwater world is an environmentally friendly world. In order to protect the environment, cars, motorcycles and other vehicles that pollute the environment have been eliminated and replaced by well-trained dolphins. Because the living space has been broadened, there are no high-rise buildings here, only rows of energy-saving bungalows.

Behind the huge water polo, there are some small green water polo. A closer look shows that there are lush trees and flowers in it, and only small animals can shuttle through them and play happily.

Although the construction of the underwater world will be very difficult, I firmly believe that as long as we exert our intelligence and dexterous hands, staying in the underwater city will never be a dream in the near future.

5. How to write the composition of marine fish? You can refer to the following information:

Most marine vertebrates breathe through gills, move with fins, have scales on their bodies, and generally have swim bladders and temperature changes in their bodies. There are more than 20,000 kinds of live fish, among which marine fish is about1.20 thousand, which is the most prosperous fish group. A brief history of research generally believes that the study of marine fish began with Aristotle, a Greek scholar in the 4th century BC. In his book Zoology, he recorded 1 15 species of Aegean fishes, and made a systematic description of their structure, reproduction and migration. The study of modern marine fish began with the Natural History of Fish published by French scholars G.B. Ju Ye Wei and A. Valencia (1828~ 1829). Since then, many countries have conducted a lot of investigations and studies on the migration, reproduction, growth, distribution and development of marine fish resources, among which Challenger and Albatross are the most important. Since 1950s, new technologies such as electron microscope have been widely used to study the occurrence, organization, physiology and ecology of marine fish. China is one of the earliest countries in the world to exploit and utilize marine fish. 1975 The ancient tomb excavated in Jiaozhou Bay, Shandong Province, confirmed that China was able to catch many kinds of marine fish as early as the Neolithic Age, namely giant salamander, barracuda and snakehead. The Chronicle of Bamboo Books (Ancient Edition) records that the Xia Dynasty was "hunting in the east and catching big fish". After the Qin and Han Dynasties, there were some protective measures for fish resources, such as "it is not advisable for fish to grow". Tu Benjun's Misunderstanding in the Sea of Fujian in the Ming Dynasty described in detail the habits and fishing dates of 129 species of fish along Fujian coast. Hao Yixing's Mistakes in the Sea and Guo Baicang's Mistakes in the Sea in the Qing Dynasty recorded the knowledge about the growth, reproduction and ecology of marine fish. After the founding of People's Republic of China (PRC), a large-scale survey of marine fish in China was carried out, and books such as Fish Survey Report in the Yellow Sea and Bohai Sea, Fish Fauna in the East China Sea, Fish Fauna in the South China Sea, and Chondrichthys Fauna in China were published successively, and studies on fish physiology, ecology and genetics were carried out.

6. Write a composition about the ocean. Hello! Providing an article about the ocean I saved should be original. You can check it for your reference.

The ocean is the blue treasure house of human food, and food is the foundation and eternal theme of human survival and development. China, the oriental giant, held his head high and supported a big family of 65.438+0.2 billion children with sweat and wisdom, accounting for 7% of the world's cultivated land and feeding 22% of the world's population.

However, with the exhaustion of land resources, the deterioration of environment and the rapid growth of population, the pressure of survival is increasing. Where is the way out? China, when she looked up from the yellow land, turned her eyes to the vast ocean and blew the horn of marching into the ocean. The ocean is an important support for human survival and development, and it is the largest treasure house of resources. Marine life is one of the richest and most important marine resources in this blue treasure house.

There are many kinds of marine life, large resources, diverse chemical components and effective biological utilization, which have great potential to provide food, medicine and energy for human beings. According to statistics, there are about 500,000 species of animals living in the ocean and coastal zone, accounting for 4/5 of the total number of animals on earth. In addition, there are 1.35 million kinds of plants growing in the ocean.

Scientific research shows that there are 2.6 trillion tons of biological resources in the world's oceans, but the development and utilization of marine life is still in the primary stage, providing only 2% of human food. It is predicted that the ocean will become the "second granary" of human beings in 2 1 century, and the arable land area is about 15 times that of land. For example, as long as the seaweed naturally growing in the offshore waters is processed into human food, the annual output is equivalent to 15 times of the current world wheat output.

If algae and plankton are included in the food range, the ocean can feed 30 billion people. Now when it comes to marine food, people will think of delicious fish, shrimp, crabs, shellfish and other animals. In fact, the focus of "marine food agriculture" is seaweed plants.

For example, one hectare of aquatic algae can extract 20 tons of protein after processing, which is equivalent to the protein content of soybeans in 40 hectares of cultivated land for one year. What an attractive development prospect! The ocean is not only the cradle of life, but also feeds a wide variety of marine animals and plants. In the vast sea, there are sparkling night insects, jellyfish with crystal clear bodies, beautiful corals, colorful shellfish, armored shrimps and crabs, puffed squid and various precious sea cucumbers, as well as grotesque fish, ancient and tenacious turtles and graceful seals, sea lions, walruses and dolphins, and huge whales.

Coral has left a good impression on people of all ages. Its branches are slender and flexible, and it is a valuable ornament after processing. In the past, people used to regard coral as a kind of plant and called it "coral tree" because it was too much like a plant. Living corals die and new corals are born again. Over the years, the calcareous bones of dead corals have formed various barrier reefs. Many islands in Xisha and Nansha Islands in China are such coral reefs.

Marine fish, there are about 30,000 species of marine fish in the world, and there are 2,000 species in China waters. Fish are colorful, colorful and strange, which is beyond the reach of any other marine life.

So, what is a real fish? The so-called true fish must meet three conditions: first, vertebrates who live in water all their lives; The second is to breathe with the gills and exercise with the fins; Third, there are real maxilla and maxilla. The cuttlefish, abalone and whale mentioned in our daily life are not real fish although they all have the word "fish" in their names.

Squid and abalone are mollusks among invertebrates, while whales are marine mammals that breathe with their lungs. Among the marine fish, the butterfly fish is the most vivid and beautiful, and the swordfish is the fastest. The swimming speed can reach 130 km per hour, which is faster than the train. The fiercest fish are sharks ... these strange marine fish have a very close relationship with humans. They are an important source of human intake of protein. protein is not only delicious on the table, but also a raw material for medicine and industry.

Marine animals are mammals that live in the sea. As we all know, mammals are the tallest animals in the biological world. From the evolutionary history, there were no mammals in the ocean, but later they returned to the ocean from land.

It is not clear when and why they will return to their hometown. The characteristics of this kind of animals are viviparous, young ones grow up on breast milk, breathe with lungs, have constant body temperature and developed nervous system.

There are 130 kinds of mammals in the ocean, such as whales, dolphins, dugong, seals and sea lions. At present, the largest blue whale caught by people is 33.5 meters long and weighs 1950 tons, which is equivalent to the weight of 35 elephants. It can eat one ton of krill in one meal and 4-5 tons of krill in one day.

Dugong, commonly known as "mermaid" or "manatee". People often say that it is the ugliest animal, and its appearance is far from "beauty". But people gave it the nickname "Mermaid", which was probably just a beautiful imagination added to the legend by scholars who had never met before, so the ugly animal became a "beauty".

Dugong is ugly, but very docile. As early as the 1960s, it was predicted that marine animals would be widely used in the military and could collect intelligence for the navy.

In recent years, countries around the world have made great progress in the study of marine animals and achieved remarkable results. Seaweed is the main body of marine plants, with about 20 thousand species. At present, there are about 65,438+000 kinds of algae that can be used as food.

There are microscopic algae that are almost invisible to the naked eye. Some are bait for fish and shrimp, and some are microalgae food for development and utilization. Microalgae are rich in protein, fat, sugar and other nutrients and minerals.

For example, the protein content of Chlorella is as high as 88.2%, and the protein content of Spirulina is as high as 7 1%. Marine macroalgae such as kelp, Undaria pinnatifida, Ulva and laver are popular marine vegetables with rich nutrition and bright colors.

Giant algae is the largest algae in the ocean, which is more than 300 meters long and can grow more than 60 centimeters every day. These large brown algae constitute the so-called "underwater forest" and become the "fertile grassland" of the marine world, which is not only.

7. Describe the composition of the ocean: including seabed sediments and marine life, beaches, estuaries, accidental killing of marine life that is not allowed to be killed by targets, coastal beach engineering construction, mangrove logging and other complex systems. Rich biological and mineral resources in the ocean. According to the investigation of the relevant departments of the United Nations, due to overfishing, heavy metals, pesticides, chemical resources and electric power resources are all indispensable resource treasures for human beings, which are closely related to human survival and development.

At present, the main goal of marine protection is to protect marine living resources from exhaustion, at least to exhaust the resources of 25 most valuable fishing grounds in the world, including whales and turtles, for sustainable use by human beings. In particular, priority should be given to the protection of precious and endangered marine life, extensive marine environmental pollution, coral reefs, spawning, foraging, manatees and many other endangered marine animals. It is predicted that with the expansion of the scale of marine development, it may cause greater damage to marine living resources.

The task of marine protection should first stop the over-utilization of marine living resources, and then protect the habitats or habitats of marine living things, especially the coastal areas where they migrate, so as to avoid the harm of the enemy and easily pollute the ocean with eutrophic oil, organic matter and nutrients. Maintain the regeneration ability of marine biological resources and the natural purification ability of seawater, maintain the marine ecological balance and ensure the sustainable development and utilization of the ocean by human beings. Marine biological environment includes seawater, dissolved substances and suspended substances in seawater.

8. There is a composition about the ocean.

The sea, I like it for my future, day and night, perseverance. Every time I see it, it is fighting for its own ideal. It grinds the sharp stone round, the round stone is smooth, the talc is small, and the small stone is traceless. How much wind and rain it has experienced! How many times have I been baptized by years! He was black and blue all over, and he still fought against difficulties and obstacles to the end.

Hai, I like his domineering. Even if the sea breeze doesn't blow, he will set off waves of sails. The waves wander in the sky again and again, pierced by the smile of the sun, and become particularly dazzling, transparent and sparkling. At this moment, I think it is more beautiful than anything!

The sea, I sometimes like its little waywardness, naughty and lovely like a child! Seagulls skim the floating line on the sea surface, and sometimes they play a little joke on this "travel team". When they fly, it will set off small waves and pat them on their bodies, sometimes photographing them. At this time, I couldn't help laughing, laughing that they were noisy and never left.

This is a composition about scenery. The little author described the characteristics of the ocean in vivid language. "The sea, I like it, sometimes small and willful, naughty and lovely like a child" and other anthropomorphic rhetorical devices add a lot of color and fluency.

9. The article describing the underwater scenery is very urgent .. The underwater world is moving and the sea is still; The bottom of the sea is black but there is light; The bottom of the sea is quiet, with the sound of fish.

& lt； Scenery at the bottom of continental shelf >

The continental shelf is a natural extension of land to the sea. Originally, the coastal plain was submerged by seawater and became a shallow sea on the continental shelf. The shallow sea on the continental shelf surrounds the landing land like a wreath, but its total area is 27.5 million square kilometers, which is equivalent to the area of the African continent. Most of the Bohai Sea, Yellow Sea and East China Sea in China are on the continental shelf.

The seafood we eat, such as fish and shrimp, is mainly caught from the shallow sea of continental shelf, and the aquatic products in the shallow sea of continental shelf account for 80% of the whole marine aquatic products.

The seabed of the continental shelf is rich in oil and natural gas, accounting for about 1/3 of the world. Many oil fields on land are also generated in the submarine environment of the continental shelf.

Beautiful shallow sea scenery

The ocean is beautiful and unpredictable. When the weather is clear, the sea is blue and the Wan Li is endless. It looks big, solemn and calm. When the storm came, it suddenly rolled up the stormy waves, which were turbulent and sinister.

Shallow sea is a colorful world, and creatures are bathed in bright and warm seawater; Wonderful little fish roam among gorgeous corals, and exotic and lovely shellfish, starfish, jellyfish and algae of various colors dance under the turbulent waves. Form a beautiful picture.

Plants on land include trees and flowers, which form a large forest, grassland or garden green space. All the plants in the ocean are called seaweeds, and some seaweeds are so small that they need to be magnified by a microscope for dozens or hundreds of times to see them. They are composed of a single cell or a string of cells, with different colors of branches and leaves, which float in the water. The growth and reproduction speed of unicellular algae is very fast, which can be increased many times a day. Although it is constantly swallowed by all kinds of fish and shrimp, the number is still huge.

In A.D. 1820, the British began to use helmet-mounted submersibles to force air into the helmet through the trachea on the surface of the water for divers to breathe. This is the predecessor of modern submersible.

Large algae are tens or even hundreds of meters long. Their soft bodies cling to the bottom of the sea and are shaken back and forth by the waves, but they are not easily broken. The economic value of seaweed is very high, such as kelp, laver and seaweed in China's shallow sea, which are all good foods, and some of them can also extract industrial raw materials and medical raw materials such as iodine, bromine and potassium chloride.

Seaweed is the food of marine animals. Some marine animals are herbivores, while others live by eating "herbivores". Therefore, all marine animals feed on seaweed.

Seaweed, like plants on land, cannot live without sunlight. Marine green plants absorb nutrients from seawater and synthesize organic matter (sugar, starch, etc.) during their life. ) meet the needs of marine plants through photosynthesis under sunlight. Photosynthesis must have sunlight. Sunlight can only penetrate the sea surface, which makes algae live only in shallow water or on the surface of the ocean, while large algae can only live at the seaside and the seabed with a water depth of tens of meters.

10. Write 300 words Underwater World This summer vacation, I attended a summer camp organized by a travel agency and went to the capital Beijing. My days in Beijing remind me. My happiest day was to go to the most famous "Rich Country Underwater World" in Beijing. Cut to the chase and write down where you want to go. )

Walking into the door of the underwater world, I took the elevator to a hall. The first thing that caught my eye was a big screen TV in the center of the hall. Some early tourists sat there watching TV with cartoons about fish. We walked on and posted photos and introductions of all kinds of fish on colorful walls.

My sisters and I were anxious to see the fish in the sea, so we rushed to hug. As soon as we walked in, we saw many fish swimming around the glass wall. There are fish on my left, right and head. They are colorful and beautiful. (A few locative words indicate that there are many fish! Suddenly, I saw several seahorses playing, a yellow seahorse and two red seahorses, both very small. I named the yellow seahorse Rourou, Red Sea Caravan. Rourou is wrapped in a piece of coral. Suddenly, she swam over, wrapped Rourou tightly, and Rourou had to stay there obediently, which lasted for a long time. I saw another chinemys reevesii, lying there lazily, and two big sharks, swimming around on the rampage, as if everywhere. (Two words write the characteristics of two kinds of fish respectively! ) There are countless fish, which dazzled me and surprised me. Two fish tails suddenly appeared in the water, one red and the other pink. I thought, what kind of fish is this? It's beautiful! Hey! It turned out to be a mermaid, alas! I am so excited that I can't take my eyes off this beautiful mermaid for a moment. I followed it through the glass. The mermaid seemed to read my mind and danced in the water. Really beautiful! The first half of the sentence describes the excitement of the little author after seeing the mermaid, and the second half describes how the mermaid saw the little author in an anthropomorphic way. Mermaids interact with each other, and mermaids blend with each other. Wonderful! )

Unconsciously, the visit was over and we left the rich underwater world. I am both happy and sad. I am glad that I have gained a lot of marine knowledge. It's a pity that time is too short and I haven't seen enough. When I go to Beijing again, I must have a good time!