《2025年实验班全程提优训练高中英语选择性必修第二册外研版》

Ⅰ. 新情境
(2025·安徽皖南八校联考)阅读理解
主题语境:人与自然 语篇类型:新闻报道 建议用时:8 min
Fire season is approaching in the massive Yukon Flats National Wildlife Refuge in east Alaska, where fires have long been allowed to burn unchecked unless they threaten human life and property. But as climate change increases the frequency of these fires, the land's overseers(监督者) are changing course. Working with scientists, refuge managers have designed a pilot programme to send experienced firefighting teams into remote areas to protect not people but permafrost(永久冻土).
The forests of the Denmark-sized refuge cover a deep layer of permafrost—frozen ground that holds enormous quantities of carbon across the Northern Hemisphere. After fires remove vegetation and soils, however, that frozen ground often begins to melt, releasing its stores of carbon dioxide ($CO_2$) and other greenhouse gases into the atmosphere. 
New research suggests that the resulting emissions, from both the fires themselves and the subsequent permafrost melt, could be equal to those of a major global economy over the course of this century. This could effectively reduce by up to 20% the amount of carbon dioxide that humanity can emit and still meet its goal of limiting global warming to 1.5°C above preindustrial levels.
A rise in fire frequency can have cascading effects(级联效应) on the ecosystem. Historically, northern forests have burnt once every 70—120 years, which gives the black-spruce(黑云杉) forest that dominates the ecosystem enough time to regenerate and rebuild carbon in the soil. More-frequent fires can burn 'legacy' carbon that has accumulated over centuries and can also kill off the black spruce. That provides an opening for leafy deciduous(落叶的) trees, which do not promote the kind of carbon-rich soils that separate permafrost.
Fire control could help to put off some of these effects, buying humanity time to address the climate crisis. It could be a few decades before scientists can determine whether the effort pays off, but we have to try.
1. How did the refuge authorities deal with fires in the past?
A. They dropped firefighters by parachute.
B. They took no measures if there was no threat.
C. They protected permafrost rather than people.
D. They sent well-trained pilots to remote areas.
2. What are Paragraphs 2 and 3 mainly about?
A. The effect of fires on permafrost.
B. The numbers of carbon emissions.
C. The advance of global economy.
D. The tendency of global warming.
3. Which is not mentioned concerning the cascading effects?
A. More emissions of greenhouse gas.
B. More destruction of black spruce.
C. The rise of leafy deciduous trees.
D. The increase in carbon-rich soils.
4. What does the author imply in the last paragraph?
A. Addressing the climate crisis is credited to firefighting teams.
B. It is no good changing the long-standing fire control policies.
C. There's still a long way to go before addressing climate crisis.
D. Our effort will definitely pay off if we protect the permafrost.

答案： 1.B 细节理解题。根据第一段中的“Fire season is approaching in the massive Yukon Flats National Wildlife Refuge in east Alaska, where fires have long been allowed to burn unchecked unless they threaten human life and property.”可知，在过去，如果火灾不威胁人类生命和财产，避难当局就不采取任何行动。故选B。
2.A 主旨大意题。根据第二段内容和第三段中的“New research suggests that the resulting emissions, from both the fires themselves and the subsequent permafrost melt, could be equal to those of a major global economy over the course of this century.”可知，这两段主要讨论了火灾对永久冻土的影响。故选A。
3.D 细节理解题。根据第四段内容可知，“级联效应”中包含黑云杉的破坏、落叶树的增多。根据第二段中的“After fires remove vegetation and soils, however, that frozen ground often begins to melt, releasing its stores of carbon dioxide （CO₂） and other greenhouse gases into the atmosphere.”可知，火灾移除植被和土壤后，冻土开始融化，释放出其储存的二氧化碳和其他温室气体到大气中。这实际上是在描述火灾（以及随后的冻土融化）导致的温室气体排放量增加，尽管没有直接用“级联效应”来标签这一过程，但这个后果是火灾频率增加后可能产生的一系列影响之一。“级联效应”中并未提到增加富含碳的土壤。故选D。
4.C 推理判断题。根据最后一段内容可知，作者认为解决气候危机还有很长的路要走。故选C。