晨读英语美文60篇六级52

The Dry Lands

　In most people’s minds the term desert conjures¹ up an image of undulating sand dunes² beneath the hot sun. There are, however, many other kinds of desert. Antarctica, Greenland and the polar ice packs are cold deserts where the water is locked up in ice. As for the Earth’s arid³ regions, they exist both in areas such as Arabia where the climate is permanently⁴ hot, and in others such as the steppes of central Asia where the winters are cold. The common denominator between them is that on average more water evaporates than falls as rain.Where there is practically no rain, as in the Sahara and the Gobi, there is virtually no life.

　Regions in which enough water falls to allow grazing and perhaps some dry farming are described as semi-arid. There are many of these in Africa, India, Argentina and Australia. Arid and semi-arid regions make up more than a third of the world’s land surface, whereas cultivated land accounts only for one-tenth. They are concentrated in two zones straddling the Tropics of Cancer and Capricorn, on each side of the Equator.

　The main cause of aridity⁵ is to be found in the circulation of the atmosphere above our revolving⁶ globe. The almost permanent ridges⁷ of high pressure that predominate around the 30olatitude mark stop rain from forming. Great distance from the oceans or the presence of mountain barriers are other factors that contribute to the aridity of regions like central Asia or the American Midwest.

　So deserts have not been created by humankind, as is something claimed, though people do contribute to decertification. In our time increased population pressure and over-intensive agriculture and grazing are accelerating soil degradation⁸ and worsening the effects of drought in semi-arid regions such as the African Sahel and northeastern Brazil.

　There is another way in which human activity may affect the evolution of arid regions. It is thought that the accumulation in the atmosphere of carbon dioxide from automobile⁹ engines, heating or industry and other gases of industrial and agricultural origin can lead to global warming through the ‘greenhouse effect’. It is not yet possible to predict the consequences of such global warming for different regions, but it may well be that in a few decades some arid regions will be direr still while others will be less so. In that case, people will have brought about a significant climatic change, comparable to those that have taken place in the course of geological history.

1 conjures   

用魔术变出( conjure的第三人称单数 )； 祈求，恳求； 变戏法； （变魔术般地） 使…出现

参考例句：

• The word 'birthday' conjures up images of presents and parties. “生日”这个词使人想起礼物和聚会的情景。
• The name Sahara conjures up images of a desert of aridity. "撒哈拉"这个名字使人想起干旱的沙漠情景。

2 dunes   

沙丘( dune的名词复数 )

参考例句：

• The boy galloped over the dunes barefoot. 那男孩光着脚在沙丘间飞跑。
• Dragging the fully laden boat across the sand dunes was no mean feat. 将满载货物的船拖过沙丘是一件了不起的事。

3 arid   

adj.干旱的；(土地)贫瘠的

参考例句：

• These trees will shield off arid winds and protect the fields.这些树能挡住旱风,保护农田。
• There are serious problems of land degradation in some arid zones.在一些干旱地带存在严重的土地退化问题。

4 permanently   

adv.永恒地，永久地，固定不变地

参考例句：

• The accident left him permanently scarred.那次事故给他留下了永久的伤疤。
• The ship is now permanently moored on the Thames in London.该船现在永久地停泊在伦敦泰晤士河边。

5 aridity   

n.干旱，乏味；干燥性；荒芜

参考例句：

• The name Sahara conjures up images of a desert of aridity. "撒哈拉"这个名字使人想起干旱的沙漠情景。 来自辞典例句
• The name conjures up images of a desert of aridity. “撒哈拉”这个名字使人想起“干旱”的沙漠情景。 来自互联网

6 revolving   

adj.旋转的，轮转式的；循环的v.（使）旋转( revolve的现在分词 )；细想

参考例句：

• The theatre has a revolving stage. 剧院有一个旋转舞台。
• The company became a revolving-door workplace. 这家公司成了工作的中转站。

7 ridges   

n.脊( ridge的名词复数 )；山脊；脊状突起；大气层的)高压脊

参考例句：

• The path winds along mountain ridges. 峰回路转。
• Perhaps that was the deepest truth in Ridges's nature. 在里奇斯的思想上，这大概可以算是天经地义第一条了。

8 degradation   

n.降级；低落；退化；陵削；降解；衰变

参考例句：

• There are serious problems of land degradation in some arid zones.在一些干旱地带存在严重的土地退化问题。
• Gambling is always coupled with degradation.赌博总是与堕落相联系。

9 automobile   

n.汽车，机动车

参考例句：

• He is repairing the brake lever of an automobile.他正在修理汽车的刹车杆。
• The automobile slowed down to go around the curves in the road.汽车在路上转弯时放慢了速度。