专题22 阅读理解（环境保护类）
1.C【2019·浙江卷】
California has lost half its big trees since the 1930s, according to a study to be published Tuesday and climate change seems to be a major factor(因素).
The number of trees larger than two feet across has declined by 50 percent on more than 46, 000 square miles of California forests, the new study finds. No area was spared or unaffected, from the foggy northern coast to the Sierra Nevada Mountains to the San Gabriels above Los Angeles. In the Sierra high country, the number of big trees has fallen by more than 55 percent; in parts of southern California the decline was nearly 75 percent.
Many factors contributed to the decline, said Patrick Mclntyre, an ecologist who was the lead author of the study. Woodcutters targeted big trees. Housing development pushed into the woods. Aggressive wildfire control has left California forests crowded with small trees that compete with big trees for resources(资源).
But in comparing a study of California forests done in the 1920s and 1930s with another one between 2001 and 2010, Mclntyre and his colleagues documented a widespread death of big trees that was evident even in wildlands protected from woodcutting or development.
The loss of big trees was greatest in areas where trees had suffered the greatest water shortage. The researchers figured out water stress with a computer model that calculated how much water trees were getting in comparison with how much they needed, taking into account such things as rainfall, air temperature, dampness of soil, and the timing of snowmelt(融雪).
Since the 1930s, Mclntyre said, the biggest factors driving up water stress in the state have been rising temperatures, which cause trees to lose more water to the air, and earlier snowmelt, which reduces the water supply available to trees during the dry season.
method英语怎么读
27. What is the second paragraph mainly about?
A. The seriousness of big-tree loss in California.
B. The increasing variety of California big trees.
C. The distribution of big trees in California forests.
D. The influence of farming on big trees in California.
28. Which of the following is well-intentioned but may be bad for big trees?
A. Ecological studies of forests.
B. Banning woodcutting.
C. Limiting housing development.
D. Fire control measures.
29. What is a major cause of the water shortage according to Mclntyre?
A. Inadequate snowmelt.    B. A longer dry season.
C. A warmer climate.    D. Dampness of the air.
30. What can be a suitable title for the text?
A. California's Forests: Where Have All the Big Trees Gone?
B. Cutting of Big Trees to Be Prohibited in California Soon
C. Why Are the Big Trees Important to California Forests?
D. Patrick Mclntyre: Grow More Big Trees in California
【答案】27. A    28. D    29. C    30. A
【解析】文章主要讲述了美国加利福尼亚州的森林面临着的巨大危机，大型树木在急剧减少，作者阐述了现象，并分析了其原因。
27. A段落主旨题。根据文章第二段第三句The number of trees…declined by 50 percent…more than 55 percent…75 percent等数字可知，该段主要讲述了加州森林中大树急剧减少的严重性，故选A项。
28. D推理判断题。根据第三段第三句Aggressive wildfire control…compete with …resources可知，由于激进的森林防火措施，虽然一定程度上保护了森林，但同时也导致小树泛滥，与大树争抢资源，从而导致大树数量骤减，所以选D项。
29. C细节理解题。根据最后一段Since the 1930s, McIntyre said…have been rising temperatures…reduces the water…可知，水资源短缺的一个主因是逐渐上升的气候温度，故选C项。
30. A主旨大意题。根据全文可知，主要讲述了美国加州森林中大树数量急剧下降的现象，并分析了原因。由此A项能很好地概括全文。
2.D【2019·北京】
By the end of the century，if not sooner，the world's oceans will be bluer and greener thanks to a warming climate，according to a new study.
At the heart of the phenomenon lie tiny marine microorganisms(海洋微生物)called phytoplankton. Because of the way light reflects off the organisms，these phytoplankton cr
eate colourful patterns at the ocean surface. Ocean colour varies from green to blue，depending on the type and concentration of phytoplankton. Climate change will fuel the growth of phytoplankton in some areas，while reducing it in other spots，leading to changes in the ocean's appearance.
Phytoplankton live at the ocean surface，where they pull carbon dioxide(二氧化碳)into the ocean while giving off oxygen. When these organisms die，they bury carbon in the deep ocean，an important process that helps to regulate the global climate. But phytoplankton are vulnerable to the ocean's warming trend. Warming changes key characteristics of the ocean and can affect phytoplankton growth，since they need not only sunlight and carbon dioxide to grow，but also nutrients.
Stephanie Dutkiewicz，a scientist in MIT's Center for Global Change Science，built a climate model that projects changes to the oceans throughout the century. In a world that warms up by 3℃，it found that multiple changes to the colour of the oceans would occur. The model projects that currently blue areas with little phytoplankton could become even bl
uer. But in some waters，such as those of the Arctic，a warming will make conditions riper for phytoplankton，and these areas will turn greener. “Not only are the quantities of phytoplankton in the ocean changing. ”she said，“but the type of phytoplankton is changing. ”

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