托福阅读材料集锦
下面是托福阅读材料的集锦，希望对你们有帮助，谢谢。
托福阅读材料：全球气候变暖
Rice yields falling under global warming
全球气候变暖也与亚洲的一些主要大米出产国的耕地面积减少有关。
Global warming is cutting rice yields in many parts of Asia, according to research, with more declines to come.
Yields have fallen by 10-20% over the last 25 years in some locations.
The group of mainly US-based scientists studied records from 227 farms in six important rice-producing countries such as Thailand, Vietnam, India and China.
This is the latest in a line of studies to suggest that climate change will make it harder to feed the world's growing population by cutting yields.
In 2004, other researchers found that rice yields in the Philippines were dropping by 10% for every 1C increase in night-time temperature.
That finding, like others, came from experiments on a research station.
The latest data, by contrast, comes from working, fully-irrigated farms that grow "green revolution" crops, and span the rice-growing lands of Asia from the Indian state of Tamil Nadu to the outskirts of Shanghai.
Describing the findings, which are published in Proceedings of the National Academy of Sciences (PNAS), lead researcher Jarrod Welch said:
"We found that as the daily minimum temperature increases, or as nights get hotter, rice yields drop."
The mechanism involved is not clear but may involve rice plants having to respire more during warm nights, so expending more energy, without being able to photosynthesise.
By contrast, higher temperatures during the day were related to higher yields; but the effect was less than the yield-reducing impact of warmer nights.
However, if temperatures continue to rise as computer models of climate project, Mr Welch says hotter days will eventually begin to bring yields down.
We see a benefit of [higher] daytime temperatures principally because we haven't seen a scenario where daytime temperatures cross over a threshold where they'd stop benefiting yields and start reducing them," he told BBC News.
"There have been some recent studies on US crops, in particular corn, that showed the drop-off after that threshold is substantial," said the University of California at San Diego researcher.
The 2007 assessment of climate impacts from the Intergovernmental Panel on Climate Change (IPCC) concluded that although a modest temperature rise could increase crop yields in some regions, for "temperature increases more than 3C, average impacts are stressful to all crops assessed and to all regions".
A study published at the begining of last year concluded that half of the world's population could face a climate-induced food crisis by 2100, with the most extreme summers of the last century becoming routine towards the end of this century.
托福阅读材料：莫斯科烟雾死亡率
Death rate doubles in Moscow's smoke, heat
高温和森林大火带来的烟尘使俄罗斯首都莫斯科的居民饱受煎熬
Scorching heat and acrid smoke have nearly doubled death rates in Moscow, a city official said on Monday, as a shroud of smog from raging forest and peat fires beset Russia's capital for a third week.
Firefighters battled wildfires covering 1,740 square km (672 sq miles) -- bigger than the area of Greater London -- in what the state weather forecaster said was Russia's worst heat wave for a millennium.
"The average death rate in the city during normal times is between 360 and 380 people per day. Today, we are around 700," Andrei Seltsovsky, Moscow's health department chief, told a city government meeting.
Russia's worst drought in decades has spooked world grain markets, driving wheat prices up at the swiftest rate in more than 30 years and raising the specter of a food crisis.
Seltsovsky said heat stroke was the main cause of the recent increase in deaths. He said ambulance dispatches in Moscow were up by about a quarter to 10,000 a day and problems linked to heart disease, bronchial asthma and strokes had increased.
"This is no secret," Seltsovsky said. "Everyone thinks we're making secrets out of it. It's 40 degrees (Celsius, or 104 Fahrenheit) on the street. Abroad, people drown like flies and no one asks questions."
Moscow morgues and hospitals were overcrowded, funeral parlors were doing a brisk business in coffins, and a sign in one crematorium said it was fully booked and taking no new orders.
"Today we have 80 bodies. We store them anywhere we can because the refrigerators are full," an attendant at Hospital No. 62's morgue, designed to hold up to 35 corpses, told Reuters.
Until Monday, neither federal nor Moscow authorities had announced data on deaths from heat and pollution, giving rise to suspicion of a Soviet-style cover-up in the face of criticism of the government's handling of the wildfire crisis.
Officials say 52 people have been killed by fires that have ravaged forests and fields and destroyed a handful of villages since late July.
ECONOMIC IMPACT
Prime Minister Vladimir Putin last week announced a grain export ban from August 15 to December 31, sending prices higher and hurting shares of brewers such as Carlsberg and Heineken.
SovEcon, a leading agricultural analyst, said on Monday the government might extend the ban even longer, reducing 2010-11 wheat exports to about 3 million tonnes instead of the earlier expected 10-11 million tonnes.
SovEcon also said Russia's wheat crop might be about one-third smaller than last year's, dropping to 43 million tonnes from 61.7 million tonnes in 2009.
Russia's main sugar lobby warned on Monday that the drought may hamper this year's beet sugar output, reducing it from the earlier expected 4 million tonnes to 3.2-3.5 million tonnes.
The downgraded sugar beet forecast is not expect to change Russia's import needs as it has large domestic reserves. Almost all sugar produced in Russia is consumed domestically.
Kremlin critics have blamed Putin for what they call a sluggish and ineffective government response to the fires, but polls have so far shown no decline in his popularity.
Russia has begun to feel economic effects from the horrid weather conditions, which have prompted banks and businesses to reduce staffing and slowed activity in the service sector.
Alfa Bank, a Moscow investment bank, said it would not publish a daily research bulletin on Monday or Tuesday.
"Owing to severe weather in Moscow, there is only a limited presence at the bank," an Alfa official said in an e-mail.
According to the business daily Kommersant, investment bank Uralsib shortened its workday on Monday, and state-controlled behemoth Sberbank closed some of its back offices.
But many Muscovites did report for work, trudging to metro stations or driving on streets where visibility was far below normal and smog veiled buildings.
Many people wore facemasks to try to filter the smoke, but the masks were increasingly hard to find and some doctors raised concerns about an official whitewash of the real impact of the smoke in Moscow.
An unnamed doctor at a Moscow clinic wrote on his Internet site over the weekend that he was wary of diagnosing patients with heat- and smoke-related illnesses for fear of dismissal.
Another doctor at a major hospital, speaking on condition of anonymity, told Reuters on Sunday that senior management had instructed staff not to link patients' illnesses with the heat.
Moscow authorities said over the weekend that reception centers were operating city-wide as refuges from the heat. But Vitaly Bredikhin, deputy manager of one of the centers, said that about 90 percent of the facilities lacked air-conditioning.
At one of the shelters, in an old building near Pushkin Square in the center of the city, about 10 elderly people sat in a hot dining room with no air-conditioning or even a fan.
托福阅读材料：美国对狼的保护
Judge orders US to keep protecting 'endangered' wolves
A federal judge has ordered the US to put Rocky Mountain grey wolves back on a list of protected endangered species.
Encouraged by the recovery of the once nearly-extinct wolf, the US last year moved to allow wolf hunts in two states while protecting them in a third.
But a judge ruled the law did not permit the US to protect part of a species population while allowing hunting of the rest.
Despite the ruling, Idaho said it would seek federal approval for a wolf hunt.
The decision puts wolves in the states of Montana and Idaho back on the endangered species list following their removal last year.
Wyoming's wolves had remained protected because the US government was unsatisfied with the state's wolf protection plan.
In Montana, US District Judge Donald Molloy came down on the side of a coalition of conservation groups who had challenged the US Fish and Wildlife Service's move to take the grey wolf off the endangered species list in Montana and Idaho.
Among several arguments, the coalition said the law did not permit the Fish and Wildlife Service to "partially delist" protected species - protecting the wolf in one state but not others.
Significant protection
"The plain language of the Endangered Species Act does not allow the agency to divide a [population segment] into a smaller taxonomy," Judge Molloy wrote.
Grey wolves were once abundant in the US, but a government-sponsored hunting programme nearly eradicated them. The wolves were gone from Montana, Idaho, Wyoming and south-western Canada by the 1930s.
The US passed the Endangered Species Act in 1973 and the wolf was listed as endangered in 1974, affording it significant protection from hunters.
In the 1990s, the government reintroduced wild wolf populations into the northern Rocky Mountains, situated in the western US.
Powerful ranching interests in the states concerned have opposed protection of the wolves, saying they threaten livestock.
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