题目内容
Plants are flowering faster than scientists predicted(预测)in reaction to climate change, which could have long damaging effects on food chains and ecosystems.
Global warming is having a great effect on hundreds of plant and animal species around the world, changing some living patterns, scientists say.
Increased carbon dioxide(CO2)in the air from burning coal and oil can have an effect on how plants produce oxygen, while higher temperatures and changeable rainfall patterns can change their patterns of growth.
“Predicting species’ reaction to climate change is a major challenge in ecology,” said the researches of several U.S. universities. They said plants had been the key object of study because their reaction to climate change could have an effect on food chains and ecosystem services.
The study, published on the Nature website, uses the findings from plant life cycle studies and experiments across four continents and 1,634 species. It found that some experiments had underestimated(低估)the speed of flowering by 8.5 times and leafing by 4 times.
“Across all species, the experiments under-predicted the speed of the advance — for both leafing and flowering — that results from temperature increases,” the study said.
The design of future experiments may need to be improved to better predict how plants will react to climate change, it said.
Plants are necessary for life on the Earth. They are the base of the food chain, using photosynthesis(光合作用)to produce sugar from carbon dioxide and water. They let out oxygen which is needed by nearly every organism on the planet.
Scientists believe the world’s average temperature has risen by about 0.8℃ since 1900, and nearly 0.2℃ every ten years since 1979.
So far, efforts to cut emissions(排放)of planet-warming greenhouse gases are not seen as enough to prevent the Earth heating up beyond 2℃ this century — a point scientists say will bring the danger of a changeable climate in which weather extremes are common, leading to drought, floods, crop failures and rising sea levels.
【小题1】What is the key information the author wants to give in Paragraph 1?
A.Plants’ reaction to weather could have damaging effects on ecosystem. |
B.The increasing speed of flowering is beyond scientists’ expectation. |
C.Climate change leads to the change of food production patterns. |
D.Food chains have been seriously damaged because of weather. |
A.plants’ flowering is 8.5 times faster than leafing |
B.there are 1,634 plant species on the four continents |
C.scientists should improve the design of the experiments |
D.the experiments failed to predict how plants react to climate change |
A.they can prove the climate change clearly |
B.they are very important in the food chains |
C.they play a leading role in reducing global warming |
D.they are growing and flowering much faster than before |
A.It has risen nearly 0.2℃ since 1979. |
B.Its change will lead to weather extremes. |
C.It is 0.8℃ higher in 1979 than that of 1990. |
D.It needs to be controlled within 2℃ in this century. |
【小题1】B
【小题2】C
【小题3】B
【小题4】D
解析
If you want your land to keep fertile, you must try to stop soil from being carried away by water or wind. When soil is taken away by flowing water or blowing winds we call it soil erosion. Ways have been found to stop soil erosion, and this is known as soil conservation. One way of stopping soil erosion is to grow small plants such as grass. These plants are referred to a cover crops, whose roots hold the soil tightly together. The rain water can not wash away the soil. When trees and tall bushes are planted at the edges of an open field, soil erosion by strong winds can not take place. The trees and bushes, which act as a very big and firm wall, protect the open land from the winds. The way to stoop soil erosion on slopes is to build terraces on the slope of hillside and mountainside. When the slope of a hillside is cut into “step”, water carrying soil can not run straight down the terraces, which are used to slow down the speed of the flowing water containing much soil in it. In this way most of the soil in the water is left behind on the terraces, much soil in it.
【小题1】What takes place in soil erosion?
A.Flood happens to the fertile land |
B.A large quantity of the soil loses away gradually. |
C.Terraces are built on the slope of hillside or mountainside. |
D.Plants are grown to protect the open land |
A. grass B. trees and bushes C. plants life and an area
E. covering plants that produce grain or vegetables
【小题3】Besides growing small plants, another method to fight against soil erosion is to ___________.
A.build terraces | B.build walls | C.plant trees | D.plant tall bushes |
A.because their roots hold soil tightly |
B.to stop soil from being blown away by winds. |
C.Because soil erosion causes terrible damages to crops |
D.To keep the balance of nature |
A.What Causes Soil Erosion |
B.The Importance of Erosion |
C.Rain Erosion and Wind Erosion |
D.Erosion and the Way of Tight against Erosion |
Scientists are trying to make the deserts ,which get very little rain, into good land again. They want to bring water to the deserts,so people can live and grow food. They are learning a lot about the deserts. But more and more of the earth is becoming desert all the time. Scientists may not be able to change the desert in time.
Why is more and more land becoming desert?Scientists think that people make deserts.People are doing bad things to the earth against the scientists’ wish.
Some places on the earth don’t get much rain. But they still don’t become deserts.This is because some green plants are growing there.Small green plants and grass are very important to dry places.Plants don’t let the sun make the earth even drier. Plants do not let the wind blow the dirt away.When a bit of rain falls,the plants hold the water. Without plants, the land can become desert more easily.
【小题1】Deserts ____________ .
A.never have any plants or animals in them |
B.can all be turned into good land before long |
C.are becoming smaller and smaller |
D.get very little rain |
A.plants can’t grow there |
B.there is not enough rain |
C.people haven’t done what scientists wish them to do |
D.scientists know little about the deserts |
A.they don’t let the sun make the earth even drier |
B.they don’t let the wind blow the soil away |
C.they hold water |
D.All of the above. |
A.plants can keep dry land from becoming desert |
B.it is good to get rid of the grass in the deserts |
C.all places without much rain will become deserts |
D.it is better to grow crops on dry land than to cut them |
阅读下列应用文及相关信息,并按照要求匹配信息。请在答题卡上将对应题号的相应选项字母涂黑。
首先请阅读关于不同月份天气特征的信息。
A. February – it’s one of the most pleasant months of the year. Most days have clear, sunny skies and the average temperature is a very cool 14°C. With an average monthly rainfall of only 20mm it is also one of the driest months.
B. April – it’s a warm spring month with moderate temperatures averaging around 21°C, and it is very wet, with 200mm rainfall on average for the month.
C. June – although it is the start of summer with average temperatures reaching a hot 28°C, you will not see much sun as it is usually very cloudy. It is also one of the wettest months of the year with frequent rain and average monthly rainfall of 240mm.
D. August – it is the hottest month of the year with average temperatures of 30°C. Generally very sunny during the day, but with frequent heavy rain showers in the evening that make it the wettest month of the year with an average monthly rainfall of 280mm.
E. October – this mid-autumn month is still pleasantly warm with average temperatures of 20°C. Days are mostly cloudy and overcast although rainfall levels are relatively low, averaging 70mm for rain for the month.
F. December – it is one of the coldest months of the year with average temperatures of 13°C. Night can be very cold. Mostly sunny, with a moderate average monthly rainfall of 60mm.
以下是五种蔬菜的种植指引,请把蔬菜与适宜种植的月份匹配起来。
1.Corn – it requires a warm weather for strong and rapid growth. As it needs very wet soil, choose a time when there will be plenty of rain. High temperatures will cause corn to lose its sweet flavour. |
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2.Tomatoes – these popular plants are easy to grow as they can resist most pests and diseases. They require low temperatures, plenty of direct sunlight and dry conditions for best results. |
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3.Onions – these are a cold-season crop, easy to grow in the right conditions. They need a moderate amount of rain to keep the soil damp, but too much will cause them to rot. They should be planted during sunny period, as they grow best with plenty of direct sunlight. |
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4.Eggplants – these are tropical or subtropical, hot-season vegetables that need lots of direct sunlight. They grow best when the weather is very hot and there is plenty of water in the soil. |
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5.Potatoes – the taste of home-grown potatoes is far superior to store bought ones. They need a mild to warm conditions and relatively dry soil for best growth. They also require cloudy, overcast conditions for most of the time to prevent sunburn. |