Nowadays people are facing lots of threats（威胁）all over the world.
A serious threat to farmers in many parts of the world is erosion（侵蚀）.Erosion happens if a large area of land is cleared of trees and is then badly treated by the farmers.The rain and winds may gradually wash away,or blow away much of the topsoil.When this happens,crops of wheat and corn become weaker and weaker until nothing grows well.If erosion continues,it will turn good land into a desert.
In the past,when erosion appeared,farmers sometimes moved to a new place to farm.Sometimes they could not move,but continued to try to grow food in the unhealthy soil.This caused them to sink into poverty.Soon some people realized that there was little rich,fertile soil in the world.The government began to try to stop erosion.
One of the first experiments to stop erosion began in the United States in 1933.The experiment was carried out in the area of the Tennessee River.Flood and bad farming in this area had ruined the land that had once been rich.As a result,most of the people living around the Tennessee River were very poor.
The government built big dams across the river and stored the water for use during the dry season,when there was no rain.The government workers also helped the farmers fertilize their soil and to learn new farming methods which could stop erosion.
In the beginning,the farmers were not interested.But soon,good healthy crops began to appear on the land where new methods were used.Ten years after that the crops were extremely good.The great success of this experiment led to similar projects in other parts of the world.
With the development of science and technology,people are trying to get rid of all the threats they are facing. However,it's not an easy job,because at the same time people are polluting their homeland.
1. Which of the following statements is NOT true about the Tennessee River area?| A．It was an area seriously affected by erosion. |
| B．It used to be a poor and infertile land. |
| C．It often suffered from floods. |
| D．It has become a model for other parts of the world to follow. |
| A．to become very poor |
| B．to lose topsoil in erosion |
| C．to become weaker and weaker until nothing grows well |
| D．to return into a desert |
| A．something can be done to prevent erosion |
| B．the importance of using new farming methods |
| C．the serious result of erosion |
| D．how erosion happens |
相似题推荐
【推荐1】When Jenny Brown, 10, developed bone cancer, her right leg below the knee was cut off to save her life. During the treatment, Jenny had a cat named Boogie, which seldom left her side as she got used to life with a prosthetic(义肢) leg. “My relationship with Boogie showed me animals think, feel, and suffer as we do,” says Jenny, now 44.
In 1994, Jenny graduated from college and began her film career in television. She also volunteered for animal rights groups. In 2002, having learned about some shocking mistreatment of farm animals, she knew she needed to help them. A year later, Jenny gave up her job to work as an animal caregiver at Farm Sanctuary(农场动物庇护所).
The next year, she opened the Woodstock Farm Sanctuary, a nonprofit organization aiming to rescue farm animals and help them recover. It gives tours of the farm from April to October and asks for volunteers and support through www.woodstockfarm.sanctuary.org. The farm website describe the backstory and the character of each of the animals living there.
In September, 2016, the sanctuary was moved to a new farm, which has an equipped kitchen, a dining hall and other buildings in High Falls, New York. The new place has allowed her team of 17 to host vegan(素食的) cooking classes and a kids’ camp.
“People love spending time with the animals.” says Jenny. “There’s a magic that happens here.”
1. What lesson did Jenny learn from Boogie?2. When did Jenny start the Woodstock Farm Sanctuary?
3. How can people find the backstory of animals on the farm?
4. What are the newly-offered activities on Jenny’s farm?
【推荐2】Edward O. Wilson, known as “ant man”, was born on June 10, 1929, in Birmingham, Alabama. His parents divorced when he was young, and he was moved frequently throughout his childhood. Wilson grew up exploring the forests and wildlife. One of these adventures left him partly blind, but they also set off his lifelong fascination with ants and their social structures.
Wilson earned his bachelor’s and master’s degrees from the University of Alabama. In 1955, he received his PhD. from Harvard and worked there until retirement.
Wilson’s early study of ants led to his first major discovery in 1959: how ants communicate through the release of chemical signals.
Later, in 1990, Wilson and German biologist Bert Hölldobler published their Pulitzer-winning The Ants. It detailed the insects’ social structure that was both valued by scholars and accessible to general readers.
Another of Wilson’s major works started in the early 1960s when he teamed up with Robert MacArthur. The pair published The Theory of Island Biogeography, where they sought to explain why different places have different numbers of species.
What many consider to be Wilson’s most important contributions to evolutionary biology came in 1975 when he published Sociobiology: The New Synthesis. The work explored the genetic roots of animal behavior and argued that genes shaped human behavior. Wilson faced accusations for these ideas but his work finally largely proved true. In 1978, his ideas on the role biology plays in human culture peaked in On Human Nature, which won him a Pulitzer in 1979.
Wilson published more than 400 scientific papers and 20 books. These achievements offered him a type of superstar status, but friends and colleagues say the polite Southerner remained down to earth. “Professor Wilson really listened and engaged with whomever he was interacting with,” said Corrie S. Moreau, who was one of Wilson’s final advisees.
1. What contributed to Wilson’s passion for ants?| A．The discovery he made about ants. | B．His disability caused by adventures . |
| C．The school education he received. | D．His boyhood time spent in nature. |
| A．The social structure of ants. | B．The distribution of different species. |
| C．The links between biology and human culture. | D．The role of chemical signals in communication. |
| A．Imaginative. | B．Modest. | C．Open-minded. | D．Independent. |
| A．The Pioneering “Ant Man” | B．Discoveries in Evolutionary Biology |
| C．A Leading Figure in Popular Science | D．The Adventure of a Pulitzer Prize Winner |
【推荐3】Levon Biss was looking at insects from his garden through a microscope he bought for his son. For fun, they unintentionally placed an insect under the lens (镜片). “It is amazingly beautiful!” they both screamed.
The father had been making a career taking photographs for advertisements. But that experience gave him a new direction. Around the world, insect populations are in decline because of habitat loss and climate change. Biss thought that if people could see what he saw through his son’s microscope, they would care more about protecting insects.
So Biss turned to macrophotography: taking close-up pictures of small things, like flowers or bugs. His work has attracted attention not just for its unusual beauty. It also raises awareness about the need for conservation.
In 2016, Biss showed his first insect project, Microsculpture. The term refers to the features of an insect’s exoskeleton, or outer shell, which develops overtime as the bug adapts to its environment.
Biss’s pictures capture the insects in all their microscopic details. Then he blows up the images until the insects become larger than life, some of them eight feet tall. But each image takes weeks to make. He uses a digital camera with a microscope lens. The camera is fixed on a computerized track, which allows Biss to take a shot, then move the camera by seven microns (微米)— a distance equals to about 1/10 the thickness of a human hair— for the next shot. In the end, Biss might take 10, 000 shots of a bug. A computer combines these small pictures into a single image.
Biss’s latest exhibition is Extinct and Endangered at the American Museum of Natural History. He selected bugs that were extinct or endangered, hoping his photographs would serve as a better purpose. “I communicate visually,” he says, “The way I work is through pictures. But I think it’s my duty to shake things up and get people to pay attention. ”
1. What made Levon Biss turn to macrophotography?| A．An expensive microscope. | B．An accidental observation. |
| C．Beautiful insects. | D．Attractive environment. |
| A．By taking a shot at them twice. | B．By adjusting the camera on a track. |
| C．By putting them in order on a computer. | D．By taking close-up pictures countless times. |
| A．Make people think about nature differently. | B．Spare no efforts to face difficulties. |
| C．Take action to save insects. | D．Get rid of the prejudice. |
| A．Wealthy and ambitious. | B．Polite and strong-willed. |
| C．Curious and easy-going. | D．Patient and responsible. |
