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2014年英語四級聽力練習:慢速VOA(6.10)

  From VOA Leaning English, this is the Agriculture Report.

  The United Nations says the world's population will increase by 34 percent by the year 2050. Scientists and others know it will be difficult to meet the food needs of so many people. A recent study shows that soybean crops and computers may help deal with the problem.

  The U.N. predicts food production must increase by 70 percent to meet the needs of a richer population. The U.N. expects more people will live in cities than in rural areas. But today there is little too low increase in the productivity of major crops.

  Kenneth Quinn is the president of the World Food Prize Foundation. He says the need to increase food production is the greatest difficulty humanity has ever faced.

  "There's going to be another 2 billion people on our planet between now and 2050 and how are we going to produce enough food for them to eat?" asked Quinn.

  Darren Drewry is a scientist at the American Space Agency, NASA. He led a study of soybeans which NASA calls the world's most important protein crop. He says researchers using a  computer were surprised to find that they were able to create a soybean plant that can be both more productive and use less water.

  "We find that there are changes to the architecture of modern soybean cultivars can be made to help us improve on many of these goals," said Drewry.

  Researchers were able to increase soybean productivity by 7 percent without using more water. The computer helped researchers do work that would have taken many years in the field. The next step is to test the computer's design.

  We spoke to Stephen Long about that. He is a professor at the University of Illinois, and one of the writers of the report on the soybean study. He told us by Skype that researchers used computer program to study what would happen if they changed the way the plant grows.

  "One of the things the modeling predicted is that there's too much leaf area so we're actually removing leaves as the plant's growing to get a lower leaf area. We're also artificially modifying the angle of the leaves as well to reflect what the model predicted," said Long.

Professor Long says it is important to find solutions to the predicted global food shortage before it happens. He says it will be 20 years before farmers can begin growing a more productive soybean once they have developed it.

  The study on soybeans was published in the journal Global Change Biology. The National Science Foundation, NASA and the Bill & Melinda Gates Foundation paid for the study.

  And that's the VOA Learning English Agriculture Report. I'm Caty Weaver.

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