Ⅰ.阅读理解
Wheat is a main source of food for people across the planet, accounting for a fifth of the calories consumed globally.But as a result of climate change, scientists believe most parts of the world where the crop is grown will be hit by water shortages by the end of the century.And the US could be among the countries worst affected, the authors of the research published in the journal Science Advances told Newsweek.
If climate change isn’t dealt with, by the year 2100,60 percent of areas that grow wheat will be hit by water scarcity—up from the current level of 15 percent, according to the international team of scientists.
Co-authors Miroslav Trnka and Song Feng told Newsweek that in their previous research, they had shown climate change may cause soil to become less moist (湿润的) across most mainland US states, including those where wheat is grown.As a result, the US could be “one of the top most affected wheat producers” in terms of the increase in areas affected by severe droughts，they said in a joint statement.
Worryingly, existing research has predicted a 4.0 to 6.5 percent drop in global wheat production per 1 degree Celsius of warming if climate change isn’t eased.And it’s unlikely that wheat can be replaced if water becomes scarce, as it’s not as thirsty as other crops and can do without water for a relatively long period of time.
“If multiple regions are affected by drought at the same time，it might be difficult to meet the demand even if the trade routes stay open and are not restricted by governmental measures，” warned Feng and Trnka.However，he said，“Studies show that if we continuously improve the sustainability and technologies in the coming decades and allow for international trade, we may overcome the negative impacts of climate change.”
文章大意：本文是一篇说明文。科学家认为由于气候变化，到21世纪末，世界上大部分种植小麦的地区将受到缺水的影响，如果气候变化不得到缓解，全球小麦的产量将会减少。
1．How will climate change hurt wheat production？__B__
A．By lowering the temperature.
B．By reducing the water supply.
C．By polluting the soil.
D．By flooding the field.
解析：细节理解题。根据第一段第二句可知，由于气候变化，小麦种植地将受到缺水的影响，又根据第四段可知，缺水会影响小麦产量。故选B。
2．What can we learn from Paragraph 3？__C__
A．Wheat production caused droughts in most mainland US states.
B．The United States is the biggest wheat producer in the world.
C．The United States will suffer a lot from climate change.
D．Climate change is closely watched by American scientists.
解析：推理判断题。根据第三段的内容，尤其是“the US could be ’one of the top most affected wheat producers’”可推知，美国将在气候变化中受到很大影响。故选C。
3．Why is wheat unlikely to be replaced by other crops in a drought？__D__
A．It is the primary food for most countries.
B．It is not influenced by global warming.
C．It is widely grown in most countries.
D．It needs less water than other crops.
解析：细节理解题。根据第四段最后一句可知，小麦不像其他作物那样那么需要水，在相当长的一段时间内没有水也能生存，因此小麦不太可能被其他作物取代。故选D。
4．In which section of a newspaper may this text appear？__B__
A．Health. B．Science.
C．Education. D．Entertainment.
解析：文章出处题。通读全文可知，这是一篇有关气候变化对小麦产量的影响的文章，由此可推知，本文可能出现在报纸的科学版块。故选B。
