时间:2018-12-16 作者:英语课 分类:2015年VOA慢速英语(九)月


英语课

The Secret Life of Roots


Plant roots are important to life on earth. Roots take in water and nutrients 1 that the plant needs to live and grow. They also help secure plants in dirt to prevent erosion - the breakdown 2 of soil by natural forces.  


Roots are the subject of a new exhibit at the United States Botanic Garden in Washington, D.C. It shows in great detail what is taking place underground and the ecosystem 3 services roots provide. 


The exhibit is called "Exposed: The Secret Life of Roots." Megan Freier went to the show recently.


"I was like, ‘Oh, an exhibit on roots (laughter). How boring can this be?' But then you walk in, and just, wow!"


Visitors to the Botanic Garden see dried roots hanging on a display wall in a large room. Some of the roots are from native prairie grasses. Others are from crop plants like wheat and corn. All of the roots are rolled up and dried up so they do not touch the floor. A few of the roots are several meters long.


Susan Pell is science and public programs manager at the U.S. Botanic Garden. She says this unexpected sight sends a powerful message to the visitors: Roots are the foundation for life.


"They are what absorb nutrients for the plants, absorb water for the plants to allow the plants to photosynthesize and to make sugars. And plants themselves are really what we depend on entirely 4 as a species."


The roots appear to be growing out of a wide view picture of a farmer's field. Visitors can also see some of the grasses outside the Botanic Garden. They are growing with garden vegetables like carrots and beets 5.  


Susan Pell takes hold of a soybean plant and explains why farmers depend on roots.   


"They have these little nodules on them which contain a bacterium 6 which fixes nitrogen. That's sort of a fancy way of saying it makes nutrients available to plants that otherwise would not be available to those plants."


And, that is important because it helps plants grow.


Louisa Baylan lives in the southeastern state of Florida. Florida’s ecosystem is very different from the grasslands 7 of the American Midwest. In the exhibit, she gets a sense of the problem in drought-stricken areas where roots run deep.


"If these have to go so deep into the ground and they need water for sustenance 8. You just really kind of wonder are we going to be able to sustain agriculture."


Program manager Susan Pell hopes visitors like Ms. Baylan leave with a new understanding of our natural systems and the urgency to protect them from environmental problems.  


Words in This Story


erosion – n. the slow wearing away of something


nodules – n. a small lump on the root of a plant


sustenance - n. something that keeps something alive


ecosystem – n. everything that exists in an environment


absorb – v. to take in something like a liquid in a natural way


foundation – n. something that provides support for something



1 nutrients
n.(食品或化学品)营养物,营养品( nutrient的名词复数 )
  • a lack of essential nutrients 基本营养的缺乏
  • Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》
2 breakdown
n.垮,衰竭;损坏,故障,倒塌
  • She suffered a nervous breakdown.她患神经衰弱。
  • The plane had a breakdown in the air,but it was fortunately removed by the ace pilot.飞机在空中发生了故障,但幸运的是被王牌驾驶员排除了。
3 ecosystem
n.生态系统
  • This destroyed the ecosystem of the island.这样破坏了岛上的生态系统。
  • We all have an interest in maintaining the integrity of the ecosystem.维持生态系统的完整是我们共同的利益。
4 entirely
ad.全部地,完整地;完全地,彻底地
  • The fire was entirely caused by their neglect of duty. 那场火灾完全是由于他们失职而引起的。
  • His life was entirely given up to the educational work. 他的一生统统献给了教育工作。
5 beets
甜菜( beet的名词复数 ); 甜菜根; (因愤怒、难堪或觉得热而)脸红
  • Beets are Hank's favorite vegetable. 甜菜根是汉克最爱吃的蔬菜。
  • In this enlargement, barley, alfalfa, and sugar beets can be differentiated. 在这张放大的照片上,大麦,苜蓿和甜菜都能被区分开。
6 bacterium
n.(pl.)bacteria 细菌
  • The bacterium possibly goes in the human body by the mouth.细菌可能通过口进入人体。
  • A bacterium is identified as the cause for his duodenal ulcer.一种细菌被断定为造成他十二指肠溃疡的根源。
7 grasslands
n.草原,牧场( grassland的名词复数 )
  • Songs were heard ringing loud and clear over the grasslands. 草原上扬起清亮激越的歌声。 来自《现代汉英综合大词典》
  • Grasslands have been broken and planted to wheat. 草原已经开垦出来,种上了小麦。 来自《简明英汉词典》
8 sustenance
n.食物,粮食;生活资料;生计
  • We derive our sustenance from the land.我们从土地获取食物。
  • The urban homeless are often in desperate need of sustenance.城市里无家可归的人极其需要食物来维持生命。
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