[ 2204阅读 ] 真题 - 4

Posted 2023-02-15 we1less

Temporary Pools

Paragraph 1: Temporary pools are freshwater habitats that retain water for only three to four months of the year or even shorter periods: typically for some eight or nine months they are dry basins without surface water. At the latitude of Canada’s southern Ontario, for example, the basin of a typical temporary pool fills with water when snow melts in March and April. Because temporary pools (by definition) have neither a surface inlet nor outlet, the water steadily recedes through evaporation and seepage into the surrounding soil, disappearing altogether from the surface in June or July. Most of the animal residents one sees in temporary pools are aquatic insects such as caddis flies, whose larvae (wingless, immature insects) are sometimes the most conspicuous animals in these communities.

1.The word “conspicuous” in the passage is closest in meaning to 

        conspicuous  adj. 引人注目的;明显的;易见的;惹人注意的

A. active

B. destructive 

C. long-lived 

D. noticeable

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Paragraph 2: At least two advantages to living in this type of habitat can be recognized. One involves predation. Fish are major predators of aquatic insects and other small freshwater creatures; however fish, at least in temperate regions over much of North America, are unable to survive the dry phase, and hence are eliminated from temporary pools. Predatory insects such as aquatic beetles and bugs and dragonfly nymphs do live in temporary pools, but there are far fewer species, and therefore a less efficient predator population than in permanent waters. Moreover, populations of the invertebrate predators in temporary pools have to develop anew every yearfrom colonizing adults or from drought-resistant eggs. All of this means that the impact of predation is reduced for aquatic animals that have adaptations to survive the dry phase of temporary pools.

        aquatic  adj. 水生的;水栖的;水的;水中的;水上的

        over much  大部分

        quatic beetles  水生甲虫

        dragonfly nymphs  蜻蜓若虫

        population  n. (地区、国家等的)人口，人口数量;

2.Why does the author mention that fish “are unable to survive the dry phase” in temporary pools over much of NorthAmerica?

A. To explain why predatory insects such as aquatic beetles and bugs and dragonfly nymphs are attracted to temporary pools

B. To make the point that temporary ponds are more advantageous for predatory insects than for fish

C. To explain why the population of fish in temporary pools must be replaced each year

D. To give one reason why small creatures in temporary pools experience relatively little predation

        predation  n. 捕食;(动物的)捕猎行为

S：why author 目的题

D：阴影

S：阴影标红

G：答案标红

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3.Paragraph 2 suggests that predatory insects in permanent waters are likely to

A. live mainly in temperate regions in NorthAmerica

B. be more numerous and efficient than predatory insects in temporary pools 

C. send groups of colonizing adults to new areas each year

D. have adaptations that prevent aquatic animals from eating them

S： suggests 推理题 predatory insects permanent

D： 

S：

G： B

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Paragraph 3: A second advantage is concerned with nutrition and growth. Temporary pools, especially in wooded sites, are fueled primarily by the energy and nutrients stored in fallen leaves and other decomposing plant detritus (nonliving matter that originated from plants). Furthermore, the dry phase of temporary pools usually supports a community of specialized herbaceous plants that can tolerate springtime flooding but grow rapidly in the moist, organically enriched soil after surface water disappears. These plants contribute to the detrital base every year. Although the food web is based mainly on detritus, the processes of decomposition in temporary pools are somewhat different from those in the detritus-based communities of streams and the shore zones of lakes. Detritus decomposes faster when exposed to air during dry periods and has a higher protein content upon flooding in spring than when submerged continuously in permanent water. The reason for this difference is that the terrestrial fungi causing the decomposition of plant detritus in the absence of surface water flourish where oxygen is not limited. In permanent waters, where detrital materials are covered by water, oxygen is not plentiful and decomposition is brought about by aquatic fungi and bacteria, which do not grow as abundantly as terrestrial fungi. Colonizing terrestrial fungi contribute much of the protein of decomposing plant materials, and in feeding experiments limnephilid caddis fly larvae of temporary pools showed a preference for decaying leaves with higher protein levels. Consequently, rapid development, which is so important to animals in transient waters, would be enhanced by the protein-rich detritus as well as by the higher summer temperatures of small bodies of water.

        Consequently  adv. 因此;所以

        rapid  adj. 迅速的;快速的;瞬间的;

        transient  adj. 转瞬即逝的;短暂的

        detritus  n. 风化物;残渣;腐殖质;瓦砾;碎石;垃圾;废物

4.Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.

  A. As a result, protein-rich detritus develops rapidly in the high summer temperatures of smaller bodies of water, helping transient animals.

B. As a result, the rapid development of protein-rich detritus improves animals’ ability to survive the higher summer temperatures of small bodies ofwater.

C. As a result, in smaller pools of water, where faster development is important, higher temperatures and protein-rich detritus help animals todevelop quickly.

D. As a result, the rapid development of animals in transient waters would enhance the protein-rich detritus of these smaller bodies of water.  

1. 找主干

2. 找逻辑词：

3. 找考点：

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5.Paragraph 3 suggests that decomposition happens faster in temporary pools than in permanent water because

A.the specialized plants in temporary pools are easier for fungi to process 

        plants  n. 植物;发电厂;

B.the high protein content of detritus in temporary pools attracts fungi

C.the higher oxygen levels of dry temporary pools allow more fungi to grow

D.the detrital materials covered by permanent water cannot support fungi

S： suggests 推理题 because 问原因 decomposition happens faster

D： 

S：

G： C

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6.According to paragraph 3, which of the following environments would provide the best food for limnephilid caddis fly larvae?

        limnephilid  湖沼石

        caddis  n. 石蛾(幼虫常用作鱼饵)

        larvae  n. 幼虫;幼体

A.Streams and the shore zones of lakes

        shore  n. 岸;(海洋、湖泊等大水域的)滨;

B.Permanent waters with aquatic fungi and bacteria

        aquatic  adj. 水生的;水栖的;

C.Water containing detritus decomposed by terrestrial fungi 

D.Smaller bodies of water with low oxygen levels

S： 细节题 environments

D： 

S：

G： C

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Paragraph 4: These principles have led to some practical applications. An increase in productivity following a dry phase underlies the practice in wetland management of alternately draining and flooding wetlands. ■ Aquatic birds such as ducks feed on larval caddis flies and other aquatic invertebrates and also on plants; the increased nutrient levels resulting from exposure of more of the bottom detritus to air and terrestrial fungi enhance productivity throughout the food web. ■ By the seventeenth century, fish farmers in Europe had learned that periodically leaving ponds dry and empty of fish yielded higher productivity in controlled ponds of carp fish than did constant water levels. ■ Through manipulation of water levels, the ponds were wintered as dry basins and periodically over a full year as well – practices that led to increased production of fish. In retrospect then, it appears that after centuries of experimentation to increase productivity in marshes and fish ponds, humans succeeded in duplicating the natural cycle of temporary pools. ■

        underlies  v. 构成…的基础;作为…的原因

7.The word “periodically” in the passage is closest in meaning to 

A. occasionally

B. completely 

C.intentionally 

D.briefly

8.According to paragraph 4, why are wetlands alternately drained and flooded in wetland management?

        wetlands  n. 湿地;沼泽地

        alternately  adv. 交替地；间隔地；轮流地

A.To limit the dry phases that interrupt and delay productivity

B.To control the number of harmful insects located in such wetlands

C.To increase the ability of farms to produce large crops of plants

D.To provide more nutrition for the animals in such wetlands

S： 细节题 why wetlands alternately drained and flooded

D： 

S：

G： C

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Paragraph 4: These principles have led to some practical applications. An increase in productivity following a dry phase underlies the practice in wetland management of alternately draining and flooding wetlands. ■ Aquatic birds such as ducks feed on larval caddis flies and other aquatic invertebrates and also on plants; the increased nutrient levels resulting from exposure of more of the bottom detritus to air and terrestrial fungi enhance productivity throughout the food web. ■ By the seventeenth century, fish farmers in Europe had learned that periodically leaving ponds dry and empty of fish yielded higher productivity in controlled ponds of carp fish than did constant water levels. ■ Through manipulation of water levels, the ponds were wintered as dry basins and periodically over a full year as well – practices that led to increased production of fish. In retrospect then, it appears that after centuries of experimentation to increase productivity in marshes and fish ponds, humans succeeded in duplicating the natural cycle of temporary pools. ■

9. Look at the four squares [■] that indicate where the following sentence could be added to the passage.

Alternate draining and flooding has also been used in aquatic farming.

Where would the sentence best fit?

10.Prose Summary

Temporary pools are freshwater habitats that typically hold water for only part of the year.

A. The larvae of many aquatic insects prefer the more dependable supply of low-level protein provided by terrestrial fungi in temporary pools to the high-level protein provided by aquatic fungi and bacteria.

B. Small aquatic animals in temporary pools face relatively little predation because fish cannot survive dry periods there and fewer predatory insects are adapted to live in such places.

C. Because of their abundant terrestrial fungi and higher oxygen levels during dry times, temporary pools provide their inhabitants with better nutrition than permanent waters do.

D. Decomposition takes longer in temporary pools than in permanent waters but often produce significant amounts of nutritious, high-protein detritus.

E. Every year, colonizing adults and drought-resistant eggs present duringearly flooding are more vulnerable to predators than aquatic animals that survive the dry phase of temporary pools.

F. By observing nature, people have learned the value of alternately draining and flooding areas and have applied this lesson to places where it does not occur naturally.