托福阅读常考话题及练习题推荐一:森林火灾(3)
1 托福阅读常考话题:森林火灾练习题
paragraph 4: However, loggers concentrated on removing those big, old, valuable, fire-resistant ponderosa pines, while fire suppression for decades let the understory fill up with Douglas fir saplings that would in turn become valuable when full-grown. Tree densities increased from 30 to 200 trees per acre, the forest's fuel load increased by a factor of 6, and the government repeatedly failed to appropriate money to thin out the saplings. When a fire finally does start in a sapling-choked forest, whether due to lightning or human carelessness or (regrettably often) intentional arson, the dense, tall saplings (young trees) may become a ladder that allows the fire to jump into the crowns of the trees. The outcome is sometimes an unstoppable inferno.
9.According to paragraph 4, why is the human preservation of Douglas fir sapling trees a threat to the ponderosa pine forest?
A. The presence of many sapling trees makes it more difficult for firefighters to reach the source of a forest fire.
B. Douglas fir saplings are expensive to maintain, leaving little government money for forest-fire suppression.
C. Saplings compete for space with the larger and more valuable fire-resistant trees.
D. Dense areas of tall sapling trees can spread fire to the crowns of larger, fire-resistant trees.
10.The word "regrettably" in the passage is closest in meaning to
A. unfortunately
B. surprisingly
C. probably
D. extremely
paragraph 5: Foresters now identify the biggest problem in managing Western forests as what to do with those increased fuel loads that built up during the previous half century of effective fire suppression. In the wetter eastern United States, dead trees rot away more quickly than in the drier West, where more dead trees persist like giant matchsticks. In an ideal world, the Forest Service would manage and restore the forests, thin them out, and remove the dense understory by cutting or by controlled small fires. But no politician or voter wants to spend what it would cost to do that.
11.What does paragraph 5 describe as a solution to the fires in Western forests?
A. The careful management of forests to reduce the buildup of fuel loads.
B. The preservation of a dense understory.
C. The occasional flooding of western forests to make them as wet as those in the East.
D. A return to the effective methods of fire suppression of the previous half century.
12.According to paragraph 5, people in the United States would probably not support the described forest-management and restoration techniques because they
A. think that the use of small, controlled fires may be too dangerous.
B. do not want to spend money on the expensive process of managing forest understory.
C. distrust the Forest Service due to the harmful fire-suppression techniques of the past.
D. do not want politicians involved in forest management.
Paragraph 2: Another factor is that the United States Forest Service in the first decade of the 1900s adopted the policy of fire suppression (attempting to put out forest fires) for the obvious reason that it did not want valuable timber to go up in smoke, or people's homes and lives to be threatened. The Forest Service's announced goal became "Put out every forest fire by 10:00 A. M. on the morning after the day when it is first reported." [■] Firefighters became much more successful at achieving that goal after 1945, thanks to improved firefighting technology. [■] For a few decades the amount of land burnt annually decreased by 80 percent. [■] That happy situation began to change in the 1980s, due to the increasing frequency of large forest fires that were essentially impossible to extinguish unless rain and low winds combined to help. [■] People began to realize that the United States federal government's fire-suppression policy was contributing to those big fires and that natural fires caused by lightning had previously played an important role in maintaining forest structure.
13.Look at the four squares [■] to insert the sentence in the passage.
Such a reduction seemed to demonstrate that the program of fire suppression was having its desired effect.
14.Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting THREE answer choices that express the most important ideas in the passage. Some answer choices do not belong in summary because the express ideas that are not presented in the passage or are minor ideas in the passage. The Question is worth 2 points.
For several reasons, forest fires have increased in number and intensity in the western United States. Drag your answer choices to the space where they belong. To remove an answer choice, double click on it.
Answer Choices
A. Fire suppression, which was initially thought to be beneficial, and logging are two human activities that have caused an increase in large forest fires.
B. Because forest fires are dangerous to people's property and a waste of valuable resources, the Forest Service currently has a policy to suppress all fires within a day.
C. The Forest Scientists has not yet discovered exactly why the climate of western United States causes some types of trees but not others to catch fire.
D. Logging is much less likely than other human activities to have effects that contribute to large forest fires.
E. The biggest problem in Western forest management is the increased amount of fire fuel available in forests as a result of human activity.
F. The United States government and the public are unwilling to cover the costs required to reduce the increased fuel loads in Western forests.