大家在备考托福tpo40阅读原文及题目part2，之前给大家带来了一些解析资料，可以对照分析一下!
tpo40阅读
TPO40阅读文本part2
Latitude and Biodiversity
When we look at the way in whichbiodiversity (biological diversity) is distributed over the land surface of theplanet, we find that it is far from even. The tropics contain many more speciesoverall than an equivalent area at the higher latitudes. This seems to be truefor many different groups of animals and plants.
Why is it that higher latitudeshave lower diversities than the tropics? Perhaps it is simply a matter of landarea. The tropics contain a larger surface area of land than higher latitudes—afact that is not always evident when we examine commonly used projections ofEarth’s curved surface, since this tends to exaggerate the areas of land in thehigher latitudes—and some biogeographers regard the differences in diversity asa reflection of this effect. But an analysis of the data by biologist KlausRohde does not support this explanation. Although area may contribute tobiodiversity, it is certainly not the whole story; otherwise, large landmasseswould always be richer in species.
Productivity seems to be involvedinstead, though perhaps its influence is indirect. Where conditions are mostsuitable for plant growth—that is, where temperatures are relatively high anduniform and where there is an ample supply of water—one usually finds largemasses of vegetation. This leads to a complex structure in the layers of plantmaterial In a tropical rain forest, for example, a very large quantity of plantmaterial builds up above the surface of the ground .There is also a large massof material, developed below ground as root tissues, but this is less apparent.Careful analysis of the above ground material reveals that it is arranged in aseries of layers, the precise number of layers varying with age and the natureof the forest. The arrangement of the biological mass ("biomass") ofthe vegetation into layered forms is termed its “structure” (as opposed to its“composition,” which refers to the species of organisms forming thecommunity) Structure is essentially thearchitecture of vegetation, and as in the case of tropical forests, it can beextremely complicated. In a mature floodplain tropical forest in the AmazonRiver basin, the canopy (the uppermost layers of a forest, formed by the crownsof trees) takes on a stratified structure. There are three clear peaks in leafcover at heights of approximately 3, 6, and 30 meters above the ground; and thevery highest layer, at 50 meters, corresponds to the very tall trees that standfree of the main canopy and form an open layer of their own. So, such a forestcontains essentially four layers of canopy. Forests in temperate lands oftenhave just two canopy layers, so they have much less complex architecture.
Structure has a strong influence onthe animal life inhabiting a site. It forms the spatial environment within whichan animal feeds, moves around shelters, lives, and breeds. It even affects theclimate on a very local level (the "microclimate") by influencinglight intensity, humidity, and both the range and extremes of temperature. Anarea of grassland vegetation with very simple structure, for example, has avery different microclimate at the ground level from that experienced in theupper canopy. Wind speeds are lower, temperatures are lower during the day (butwarmer at night), and the relative humidity is much greater near the ground.The complexity of the microclimate is closely related to the complexity ofstructure in vegetation, and generally speaking, the more complex the structureof vegetation, the more species of animal are able to make a living there. Thehigh plant biomass of the tropics leads to a greater spatial complexity in theenvironment, and this leads to a higher potential for diversity in the livingthings that can occupy a region. The climates of the higher latitudes aregenerally less favorable for the accumulation of large quantities of biomass;hence, the structure of vegetation is simpler and the animal diversity isconsequently lower.
本文是托福tpo40阅读原文及题目part2。
paragraph 1
When we look at the way in whichbiodiversity (biological diversity) is distributed over the land surface of theplanet, we find that it is far from even. The tropics contain many more speciesoverall than an equivalent area at the higher latitudes. This seems to be truefor many different groups of animals and plants.
1. The word “distributed” in thepassage is closest in meaning to
A. represented
B. collected
C. spread
D. managed
The word “overall” in the passageis closest in meaning to
A. considered as a whole
B. to some degree
C. possibly
D. evidently
paragraph 2
Why is it that higher latitudeshave lower diversities than the tropics? Perhaps it is simply a matter of landarea. The tropics contain a larger surface area of land than higher latitudes—a fact that is not always evidentwhen we examine commonly used projections of Earth’s curved surface, since this tendsto exaggerate the areas of land in the higher latitudes—and some biogeographers regard thedifferences in diversity as a reflection of this effect. But an analysis of thedata by biologist Klaus Rohde does not support this explanation. Although areamay contribute to biodiversity, it is certainly not the whole story; otherwise,large landmasses would always be richer in species.
3. Which of the sentences belowbest expresses the essential information in the highlighted sentence in thepassage? Incorrect choices change the meaning in important ways or leave outessential information.
A. Some biogeographers believe thatthe tropics have larger surface areas than they actually do because of thedistortions produced by projections of Earth’s curved surface
B. High levels of diversity in the tropics are sometimesattributed to the fact that the tropics have more surface area of land than thehigher latitudes do, though distortions in commonly used projections may seemto suggest otherwise.
C. Because biogeographers disagreeon whether or not the tropics are correctly represented in projections of Earths surface, it is difficult to determine the relationship their surface area hasto their diversity
D. Most biogeographers agree thatthe tropics contain a larger surface area of land than higher latitudes do，but they disagree on whether or notthe tropics’ level of diversity is a reflection of that larger surface area.
4. Why does the author mention “KlausRohde” in the passage?
A. To support the argument thatlarge landmasses are usually richer in species than smaller ones are
B. To introduce the argument that there are other factorscontributing to species diversity besides land area
C. To cast doubt on whether thetropics actually contain higher species diversity than land at higher latitudesdoes
D. To emphasize that biogeographersand biologists differ in their approaches to biodiversity
paragraph 3
Productivity seems to be involvedinstead, though perhaps its influence is indirect Where conditions are mostsuitable for plant growth—that is, where temperatures are relatively high anduniform and where there is an ample supply of water—one usually finds largemasses of vegetation. This leads to a complex structure in the layers of plantmaterial. In a tropical rain forest, for example, a very large quantity ofplant material builds up above the surface of the ground.There is also a largemass of material, developed below ground as root tissues, but this is lessapparent Careful analysis of the above ground material reveals that it isarranged in a series of layers, the precise number of layers varying with ageand the nature of the forest. The arrangement of the biological mass("biomass") of the vegetation into layered forms is termed its"structure" (as opposed to its “composition,” which refers to thespecies of organisms forming the community) Structure is essentially the architecture of vegetation, and as in thecase of tropical forests, it can be extremely complicated. In a maturefloodplain tropical forest in the Amazon River basin, the canopy (the uppermostlayers of a forest, formed by the crowns of trees) takes on a stratifiedstructure. There are three clear peaks in leaf cover at heights ofapproximately 3, 6, and 30 meters above the ground; and the very highest layer,at 50 meters, corresponds to the very tall trees that stand free of the maincanopy and form an open layer of their own. So, such a forest containsessentially four layers of canopy. Forests in temperate lands often have justtwo canopy layers, so they have much less complex architecture.
5. Which of the following is NOTmentioned in paragraph 3 as a condition that benefits plant growth?
A. High temperatures
B. Steady temperatures
C. High latitude
D. Plentiful water
6. The word “precise” in thepassage is closest in meaning to
A. exact
B. predicted
C. approximate
D. required
7. Paragraph 3 mentions which ofthe following as creating the structural complexity of a forest?
A. The height of the very tallesttrees in the forest
B. The number of layers of canopy
C. The frequency of floods alongthe plain
D. The age of the root tissuesbelow the ground
8. According to paragraph 3, whichof the following statements best describes the difference between structure andcomposition?
A. “Structure” refers to thearrangement of plant material above the ground surface; “composition” refers to thearrangement of root tissues below the surface of the ground.
B. “Structure” refers to the age ofthe forest; “composition” refers to the forest's nature.
C. “Structure” refers to the arrangement of plant speciesin an area, “composition” refers to which plant species are present in thearea.
D. “Structure” refers to the shapeof the forest canopy; “composition” refers to the number of crowns forming thecanopy.
9. Why does the author mention “mature floodplain tropical forest in the Amazon River basin” in the passage?
A. To dispute the idea thattropical forests are arranged in layers
B. To give an example of the complex architecturevegetation displays in a dense area
C. To suggest that the layers ofcanopy in some tropical forests can exceed the usual three or four
D. To emphasize that the layers ofcanopy in a tropical forest give evidence of the number of layers of roottissues below the ground
paragraph 4
Structure has a strong influence onthe animal life inhabiting a site. It forms the spatial environment withinwhich an animal feeds, moves around shelters, lives, and breeds. It evenaffects the climate on a very local level (the "microclimate") byinfluencing light intensity, humidity, and both the range and extremes oftemperature. An area of grassland vegetation with very simple structure, forexample, has a very different microclimate at the ground level from thatexperienced in the upper canopy. Wind speeds are lower, temperatures are lowerduring the day (but warmer at night), and the relative humidity is much greaternear the ground. The complexity of the microclimate is closely related to thecomplexity of structure in vegetation, and generally speaking, the more complexthe structure of vegetation, the more species of animal are able to make aliving there. The high plant biomass of the tropics leads to a greater spatialcomplexity in the environment, and this leads to a higher potential fordiversity in the living things that can occupy a region. The climates of thehigher latitudes are generally less favorable for the accumulation of largequantities of biomass; hence, the structure of vegetation is simpler and theanimal diversity is consequently lower.
10. Which of the following is NOTmentioned in paragraph 4 as an aspect of microclimate?
A. Temperature range
B. Relative humidity
C. Light intensity
D. Seasonal variations
11. What can be inferred fromparagraph 4 about a region with a high level of diversity of animal species?
A. It also has a high level of plant species diversity.
B. It has relatively fewmicroclimates
C. It develops a less complexstructure than does a region with a high plant species diversity.
D. It develops a biomass similar tothat of higher latitudes
The word “consequently” in thepassage is closest in meaning to
A. usually
B. obviously
C. however
D. therefore
13. Look at the four squares [■] that indicate where the following sentence could be added to thepassage.
One example of such tropicalabundance is found in Panama, which has 667 species of breeding birds一three times the number found inAlaska.
Where would the sentence best fit?Click on square [■] to add the sentence to the passage.
When we look at the way in which biodiversity (biological diversity) isdistributed over the land surface of the planet, we find that it is far fromeven. The tropics contain many more species overall than an equivalent area atthe higher latitudes. This seems to be true for many different groups ofanimals and plants. [■]
Why is it that higher latitudeshave lower diversities than the tropics? [■] Perhaps it is simply a matter ofland area. [■] The tropics contain a larger surface area of land than higherlatitudes—a fact that is not always evident when we examine commonly usedprojections of Earth’s curved surface, since this tends to exaggerate the areasof land in the higher latitudes—and some biogeographers regard the differencesin diversity as a reflection of this effect. [■] But an analysis of the data bybiologist Klaus Rohde does not support this explanation. Although area maycontribute to biodiversity, it is certainly not the whole story; otherwise,large landmasses would always be richer in species.
本文就是托福tpo40阅读原文及题目part2。
14. Directions:An introductorysentence for a brief summary of the passage is provided below. Complete thesummary by selected THREE answer choices that express the most important ideasin the passage.Some sentences do not belong in the summary because they expressideas that are not presented in the passage or are minor ideas in thepassage.This question is worth 2 points.
Drag your choices to the spaces where theybelong. To review the passage, click on View Text
A number of factors may helpaccount for the difference in biodiversity between low and high latitudes.
Answer Choices
A. Though land area may be related to a region'sbiodiversity, it is not a primary determining factor
B. A structure of varying heightsis found in both tropical and temperate forests.
C. The more complex the structure of the vegetation of aregion, the more species it is able to support.
D. Regions possessing conditions that are favorable forplant growth tend to have abundant and diverse vegetation that supports a largenumber of species.
E. The difference in microclimatebetween a ground-level canopy and an upper-level canopy is responsible for thenumber of species that inhabit each canopy.
F. The temperature range of aregion determines the number of animals that feed, move around, shelterthemselves, live, and breed in that region.
以上的资料是托福tpo40阅读原文及题目part2，一起来认真分析一下吧，希望对你们有帮助!