雅思机经听力试题--介绍海洋生物

雅思机经听力试题--介绍海洋生物
(总分：18.00，做题时间：120分钟)
一、海洋生物学的研究 (总题数：1，分数：1.00)
1.Why the current study statistics are more accurate than the past?
（分数：1.00）
A.Because the study range is wider. √
B.Because the current equipment is more advanced.
C.Because of the devotion of the ocean explorers. √
D.Because of the use of multi-disciplinary approach.
E.Because of people’s rising concern about the ocean exploration
解析：Though the possibilities for ocean exploration are nearly infinite, environmental and human health are facing great risks. Fortunately, thanks to the work of past and present ocean explorers, the public is increasingly aware of these risks which encourage public agencies to take action and promote research. Now the study statistics are obviously more accurate than the past due to the efforts of the workers. At the same time, it is also due to the wider scope of survey. Already the US Commission on Ocean Policy favors multi-disciplinary research to shape ocean policy. The efforts of public agencies using a multi-disciplinary approach together with the efforts provided by numerous private marine conservation organizations that work on issues such as advocacy, education, and research will help drive the momentum needed to face the challenges of preserving the oceans.
二、物种灭绝问题(总题数：1，分数：2.00)
Listen to the statement and circle the appropriate letter.（分数：2.00）
(1).What is the topic of this statement?（分数：1.00）
A.the impact of human activities on environment
B.the impact that a species’ extinct ion has on others √
C.species conservation
解析：A species becomes extinct when the last existing member of that species dies. And the extinction of one species' wild population can have knock-on effects, causing further extinctions. These are also called "chains of extinction". All wild populations of living things have many complex intertwining links with other living things around them. Large herbivorous animals such as the hippopotamus have populations of insectivorous birds that feed off the many parasitic insects that grow on the hippo. If the hippos should die out, so too will these groups of birds, leading to further destruction as other species dependent on the birds are affected. Also referred to as a Domino effect, this series of chain reactions is by far the most destructive process that can occur in any ecological community.
(2).Which of the following presents the Domino effect in ecological community?（分数：1.00）
A.The symbiotic relationship between different species.
B.The extinction of the hippopotamus affects the existence of other species dependent on them. √
C.The descent of species.
解析：
三、人类对海獭的猎捕(总题数：1，分数：3.00)
Listen to the statement and complete the following sentences with NO MORE THAN TWO WORDS.（分数：3.00）
(1).The native people of Alaska have access to the sea otters killing only if the harvest is 1 .（分数：1.00）
填空项1:__________________ （正确答案：not wasteful）
解析：Alaska Natives who reside in Alaska and who dwell on the coast of the North Pacific Ocean or the Arctic Ocean may harvest sea otters for subsistence purposes or the creation and sale of Native articles of handicraft or clothing if the harvest is not wasteful. A Native must be one-fourth degree or more Alaska Indian, Aleut or Eskimo or be enrolled under the Alaska Native Claims Settlement Act. It is illegal for a person who is not Indian, Aleut, or Eskimo to actively participate in any manner in hunting sea otters. However, Alaska Natives are not limited by Federal Law in the number that can be harvested providing the harvest is not wasteful. Numbers killed should be limited to what can reasonably be utilized. Sea otters may be harvested any time during the year.
(2).The harvest carried out by non-native people is 1 .（分数：1.00）
填空项1:__________________ （正确答案：illegal）
解析：
(3).The natives can harvest sea otters 1 during the year with a limited number. （分数：1.00）填空项1:__________________ （正确答案：any time）
解析：
四、海獭数量的变化(总题数：1，分数：4.00)
数：4.00）
填空项1:__________________ （正确答案：human's activities）
解析：The changes of the sea otters' population were mainly related to human's activities. Back in the late 18th century after North America was discovered, the Europeans heavily hunted sea otters around the West Coast of North America. Unlike other marine mammals, sea otters have very little fat. In order to adapt to the cold water temperature during the winter period, they have very dense furred skin, which acts as great insulator. Because of this, the thick furred skin was what the hunters were going after for the commercial trade. The great fur hunt went on for 170 years until early 1900's when the Fur Seal Agreement was signed. At that time sea otters' population fell to a point that they became extinct in many areas.
填空项1:__________________ （正确答案：the West Coast）
解析：
填空项1:__________________ （正确答案：thick (or dense) furred skin）
解析：
填空项1:__________________ （正确答案：170 years）
解析：
五、海獭与海胆之间的数量关系(总题数：1，分数：3.00)
Listen to the statement and circle the appropriate letter.（分数：3.00）
(1).From the passage, we can conclude that when the number of sea otter rises, the number of sea urchins will __________ .（分数：1.00）
A.fall √
B.rise
C.remain the same
解析：Off the coast of western North America, however, sea otters feed on the urchins and can prevent them from becoming too abundant, thereby keeping the kelp forests intact. This ecological balance among sea urchins, sea otters, and kelps became upset during the nineteenth century, when the populations of the otters were virtually wiped out by excessive hunting for the fur trade. Because of the collapse of otter populations, the urchins became more abundant. Their excessive
feeding on kelps greatly reduced the extent and luxuriance of the kelp forests. Fortunately, this balance has been restored by the cessation of the hunting of sea otters, allowing them to control the abundance of the urchins again. In turn, the productive kelp forests have been able to redevelop.
(2).This ecological balance among sea urchins, sea otters, and kelps became __________ during the nineteenth century.（分数：1.00）
A.upset √
B.satisfactory
C.neutral
解析：
(3).When the number of the sea urchins decreases, the kelp will _________ .（分数：1.00）
A.be extinct.
B.flourish again. √
C.keep unchanged.
解析：
六、海底生物(总题数：1，分数：3.00)
Listen to the statement and complete the following sentences with NO MORE THAN THREE WORDS.（分数：3.00）
(1). 1 now prey on sea otters rather than their traditional preys.（分数：1.00）
填空项1:__________________ （正确答案：Killer whales）
解析：As the sea otter populations recover nicely in many areas, scientists have found new threats that can cause deforestation of kelp communities once again. In recent years, a scientist has found killer whales feeding on sea otters instead on their usual diet, namely, sea lions and seals. This new food chain can derive from many factors. Ecologists believe that killer whales change their preys because the declining of seal or sea lion populations caused by the diminishing food source-fish, salmon in particular. Although the killer whales' predation eliminates the sea otters at a much slower rate than the historical great fur hunt, the scientist mentioned above has already found many otter's colonies in parts of the Aleutian Islands are nearly wiped out.
(2).The number of seal or sea lion declines due to the 1 .（分数：1.00）
填空项1:__________________ （正确答案：diminishing food source）
解析：
(3).In parts of the Aleutian Islands, many otter’s habitats are nearly 1 .（分数：1.00）
填空项1:__________________ （正确答案：wiped out）
解析：
七、海草森林(总题数：1，分数：2.00)
Listen to the statement and circle the appropriate letter.（分数：2.00）
(1).What is the topic of this statement?（分数：1.00）
A.sea urchins
B.sea otters
C.the relationship of many sea living creatures in the kelp forest √
解析：The kelp forest community supports important commercial and sport fish, such as lingcod, rockfish, salmon, and herring. On the kelp blades and holdfasts, sea urchins, snails, and sea stars graze the kelp, attached algae, and encrusting invertebrates. Many fish associated with the kelp forests prey upon these invertebrates. Horse mussels, clams, sponges, tunicates, anemones, and bryozoans attach on the rocky substrate around the holdfasts. Crabs, worms, and other detritus feeders consume dead kelp and other organic matter generated by the kelp and associated species. Sea otters and harbor seals also use kelp for foraging and resting. By consuming large numbers of sea urchins, sea otters act as a keystone species structuring the kelp forest community. However,
many experts predicate that the number of kelp will decline again in the future, which means that the ecological balance will be destroyed.
(2).What is the trend of the kelp forest in the future?（分数：1.00）
A.increasing
B.declining √
C.keeping balance
解析：。