Coral reefs are underwater structures made from calcium carbonate secreted by corals. Coral reefs are colonies of tiny living animals found in marine waters that contain few nutrients. Most coral reefs are built from stony corals, which in turn consist of polyps that cluster in groups.

Coral reefs

A Coral reefs are estimated to cover 284,300 km2 just under 0.1% of the oceans' surface area, about half the area of France. The Indo-Pacific region accounts for 91.9% of this total area.Southeast Asia accounts for 32.3% of that figure, while the Pacific including Australia accounts for 40.8%. Atlantic and Caribbean coral reefs account for 7.6%. Yet often called “rainforests of the sea", coral reefs form some of the most diverse ecosystems on Earth. They provide a home for 25% of all marine species, including fish, mollusks (软体动物), worms, crustaceans(甲壳类小动物), echinoderms(棘皮动物),sponges, tunicates and other cnidarians. Paradoxically, coral reefs flourish even though they are surrounded by ocean waters that provide few nutrients. They are most commonly found at shallow depths in tropical waters, but deep water and cold water corals also exist on smaller scales in other areas. Although corals exist both in temperate and tropical waters, shallow-water reefs form only in a zone extending from 30° N to 30° S of the equator. Deep water coral can exist at greater depths and colder temperatures at much higher latitudes, as far north as Norway. Coral reefs are rare along the American and African west coasts. This is due primarily to upwelling and strong cold coastal currents that reduce water temperatures in these areas (respectively the Peru, Benguela and Canary streams). Corals are seldom found along the coastline of South Asia from the eastern tip of India (Madras) to the Bangladesh(孟加拉国)and Myanmar borders. They are also rare along the coast around northeastern South America and Bangladesh due to the freshwater release from the Amazon and Ganges Rivers(恒河), respectively.

B Coral reefs deliver ecosystem services to tourism, fisheries and coastline protection. The global economic value of coral reefs has been estimated at as much as $US375 billion per year. Coral reefs protect shorelines by absorbing wave energy(潮汐能), and many small islands would not exist without their reef to protect them.

C The value of reefs in biodiverse (微生物多种多样的) regions can be even higher. In parts of Indonesia and the Caribbean where tourism is the main use, reefs are estimated to be worth US$1 million per square kilometer, based on the cost of maintaining sandy beaches and the value of attracting snorkelers (潜水者)and scuba divers (水肺潜水). Meanwhile, a recent study of the Great Barrier Reef in Australia found that the reef is worth more to the country as an intact ecosystem than an extractive reserve for fishing. Each year more than 1.8 million tourists visit the reef, spending an estimated AU$4.3 billion (Australian dollars) on reef-related industries from diving to boat rental to posh island resort stays. In the Caribbean, says UNEP, the net annual benefits from diver tourism was US$2 billion in 2000 with US$625 million spent directly on diving on reefs. Further, reef tourism is important source of employment, especially for some of the world's poorest people. UNEP says that of the estimated 30 million small-scale fishers in the developing world, most are dependent to a greater or lesser extent on coral reefs. In the Philippines, for example, more than one million small-scale fishers depend directly on coral reefs for their livelihoods. The report estimates that reef fisheries (渔场) were worth between $15,000 and $150,000 per square kilometer a year, while fish caught for aquariums (水族馆) were worth $500 a kilogram against $6 for fish caught as food. The aquarium fish export industry supports around 50,000 people and generates some US$5.5 million a year in Sri Lanka along.

D Unfortunately, coral reefs are dying around the world. In particular, coral mining, agricultural and urban runoff(进水), pollution (organic and inorganic), disease, and the digging of canals and access into islands and bays are localized threats to coral ecosystems(生态体系). Broader threats are sea temperature rise, sea level rise and pH changes from ocean acidification (碱化) , all associated with greenhouse gas emissions. Some current fishing practices are destructive and unsustainable. These include cyanide fishing, overfishing and blast fishing. Although cyanide (氰化氢毒)fishing supplies live reef fish for the tropical aquarium market, most fish caught using this method are sold in restaurants, primarily in Asia, where live fish are prized for their freshness. To catch fish with cyanide, fishers dive down to the reef and squirt cyanide in coral crevices and on the fast-moving fish, to stun the fish making them easy to catch. Overfishing is another leading cause for coral reef degradation. Often, too many fish are taken from one reef to sustain a population in that area. Poor fishing practices, such as banging on the reef with sticks (muro-ami), destroy coral formations that normally function as fish habitat. In some instances, people fish with explosives (爆款) (blast fishing), which blast apart the surrounding coral.

E Tourist resorts that empty their sewage directly into the water surrounding coral reefs contribute to coral reef degradation. Wastes kept in poorly maintained septic tanks can also leak into surrounding ground water, eventually seeping out to the reefs. Careless boating, diving, snorkeling and fishing can also damage coral reefs. Whenever people grab, kick, and walk on, or stir up sediment (沉淀) in the reefs, they contribute to coral reef destruction. Corals are also harmed or killed when people drop anchors on them or when people collect coral.

F To find answers for these problems, scientists and researchers study the various factors that impact reefs. The list includes the ocean's role as a carbon dioxide sink, atmospheric changes, ultraviolet light (紫外光光) , ocean acidification, viruses, impacts of dust storms carrying agents to far flung reefs, pollutants, algal blooms and others. Reefs are threatened well beyond coastal areas. General estimates show approximately 10% of the world’s coral reefs are dead. About 60% of the world's reefs are at risk due to destructive, human-related activities. The threat to the health of reefs is particularly strong in Southeast Asia, where 80% of reefs are endangered.

G In Australia, the Great Barrier Reef(大堡礁) is protected by the Great Barrier Reef Marine Park Authority, and is the subject of much legislation, including a biodiversity action plan. Inhabitants of Ahus Island, Manus Province, Papua New Guinea, have followed a generations-old practice of restricting fishing in six areas of their reef lagoon(环礁湖). Their cultural traditions allow line fishing, but not net or spear fishing. The result is both the biomass and individual fish sizes are significantly larger than in places where fishing is unrestricted.

Questions 14-19

Reading Passage 1 has seven paragraphs A-G.

Which paragraph contains the following information?

Write the correct letter A-G, in boxes 14-19 on your answer sheet.

NB You may use any letter more than once.

14 Geographical //location.href of world’s coral reef

15 How does coral reef benefit economy locally

16 The statistics of coral reefs economic significance

17 The listed reasons for declining number of coral reef

18 Physical approach to coral reef by people

19 Unsustainable fishing methods are applied in regions of the world

Questions 20-25

Do the following statement agree with the information given in Reading Passage 2?

TRUE if the statement is true

FALSE if the statement is false

NOT GIVEN if the information is not given in the passage

20 Coral reefs provide habitat to variety of marine life.

21 Coral reef distribute around the ocean disproportionally.

22 Coral reef is increasingly important for scientific purpose.

23 Coral reefs are greatly exchanged among and exported to other counties.

24 Reef tourism is of economic essence generally for some poor people.

25 As with other fishing business, coral fishery is not suitable to women and


Questions 26

Choose the correct letter. A, B, C or D.

Write your answers in boxes 26 on your answer sheet.

What is the main purpose of the this passage

A Demonstrate how coral reef grow in the ocean

B To tell that coral reef is widely used as a scientific project

C Present the general benefits and an alarming situation of coral reef

D To show the vital efforts made to protect coral reef in Australia

以上张老师为大家带来的就是关于雅思阅读 杏彩开奖的内容

你和雅思的故事 - Go Hard or Go Home

发表于 2019-09-19


Coral Reefs


Coral pigment algae Fringing atoll conch urchin polyp

A coral reef is one of the most beautiful structures found in the ocean of the world. A coral reef is formed in the sea by living things. Corals are a variety of colors due to natural pigments. They can be white, red, pink, green, blue, orange and purple.


Reef-building corals are types of animals that act like plants. They stay in one place and like plants, receive some of their energy from the sun. A type of microscopic algae lives inside the coral and provides them with food and help allow the coral reefs to grow faster.


The majority of coral reefs can be found in clear, tropical oceans, and form in shallow water or in water about 150 feet below the surface because of their need of light to survive. There are three types of coral reefs: fringing reefs, barrier reefs, and atolls.


Fringing reefs are along the coastal shorelines of continents and islands. They can be found in Hawaii and the Caribbean.


Barrier reefs are offshore, and are also found in the Caribbean, but are also located in the Indo-Pacific.


Atolls are also found in the Indo-Pacific and are a series of shallow coral islands which surround a lagoon. The largest coral reef in the world is in Australia, which is called the Great Barrier Reef. It is over 1200 miles.


The habitat of a coral reef includes water that is between 68 and 82°F and located usually along the eastern shores of land. Ocean waves bring in food, nutrients, and oxygen to the reef, which is essential for the coral reef's survival. The waves also prevent sediment from settling on the reef. In addition, the calcium from the water is needed, which is usually available in shallow warm waters.


The plants of the coral reefs grow through the process of #photosynthesis# converting the sunlight into energy. Just like on dry land, the animals of the coral reefs eat the plants to get their energy, as in a food chain. Algae, seagrasses and zooxanthellae are the main types of plants in the coral reef. The plants provide the animals food and oxygen. The seagrasses, too, provide shelter for immature reef animals like conch and lobster.


Coral reefs make up one percent of the ocean floor but is home to 25% of life in the ocean. Animals either begin their life and reside in coral reefs, or the reef serves as a type of rest stop for animals as they travel through the seas. The corals themselves, made up of tiny organisms called polyps, are the most plentiful animal on the reef. They are attached to the hard reefs and live there forever. Other animals that live on the coral reef are sponges, sea urchins, octopus, snails, worms, sharks, lobster, and many more. The animals live together and work as a team to survive.

杏彩开奖占有了深海的1%,但却 栖居着25%的等除油.杏彩开奖是许多等除油的性命开始,都是诸多等除油在旅游中途的歇息站.珊瑚丛是由这种很小的微生物菌种构成的.这类微生物菌种被称作珊瑚虫,这类微生物菌种构成杏彩开奖的小动物行为主体.他们贴附与硬实的杏彩开奖上,而且永久性地存活在哪里.定居在杏彩开奖上的微生物也有海棉微生物、海胆、鸡蛋、薇女坊、大白鲨、小龙虾这些.这种微生物一块儿存活,合作寻食.

Coral reefs are helpful to the planet as well. They remove and recycle carbon dioxide from the air which can contribute to global warming. Reefs also protect the land from the impact of strong waves during harsh weather. Unfortunately, pollution, irresponsible fishing, and sewage, among others, is responsible for the destruction of many coral reefs by humans.


In summary, coral reefs are beautiful structures of living plants and animals located throughout the seas of the world. The are found on shorelines, off- shore, and can form islands called atolls.



1) Where do coral reefs get their energy?

A: The ocean itself B: The ocean's surface

C: The sun D: The land surrounding it

2) Where is the majority of coral reefs found?

A: Lakes and rivers B: Ponds and streams

C: Tropical oceans D: Arctic waters

3) All of the following are types of coral reefs EXCEPT:

A: Fringing reefs B: Coastal reefs

C: Barrier reefs D: Atolls

4) Which of the following is the //location.href of the Great Barrier Reef?

A: Australia B: South America

C: North America D: Asia

5) Which of the following are the main types of plants in the coral reef?

A: Algae B: Seagrasses

C: Zooxanthellae D: All of the above

6) Which of the following is the most plentiful animal on Earth?

A: Polyps B: Algae

C: Urchins D: Sponges

以上范老师为大家带来的就是关于雅思阅读 杏彩开奖的内容

发表于 2019-09-19
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