[交流] 每周一听——那些年我们一起练过的听力（第35期）已有59人参与

每周一听——那些年我们一起练过的听力（第35期）

在职期间做的最后一期听力活动啦，希望大家捧场哦！！！感谢各位虫子一直以来的支持！！！

注意：本期活动，答题方式变更。参与活动的虫子请把自己的答案以站内信的方式发送至本版版主（本期发给我）并在活动帖里占位回复，方便评分，下周六下期活动发布之前有效哦。还有其他不懂之处，请在此帖里面直接留言回复，我们将尽快回答。
奖项——听写后正确填空者可得BB奖励
评分规则：
每篇设空十处，难度逐渐增加，每答对一空奖励一个BB，答对第十空奖励2BB。全对的虫子可得15个BB奖励。大家加油哦~~~~~~

Studies show farmland in Africa is often lacking in important nutrients. But researchers say a combination of farming   (1)  may help.
Since the world food crisis several years ago, researchers have directed more of their attention to small farms. Most farms in areas south of the Sahara Desert are only about one or two hectares. One of the goals is to increase production without necessarily   (2)  more land to grow additional crops.
American researchers say that can happen with greater use of an   (3)  system called perenniation. It mixes food crops with trees and perennial plants – those that return year after year.
Soil scientist John Reganold is with Washington State University.
JOHN REGANOLD: “One of the major problems (is that the) soils are   (4)  poor in most of the regions. So how do you grow food on poor soils? There have to be food production systems that can build the soil and improve the   (5)  .”
Mr. Reganold says poor soil may have resulted from years of weathering that washed away many nutrients. He says some farmers may have done more harm than good.
JOHN REGANOLD: “They have been actually using  (6)  where they’re not putting in organic matter. They’re not putting in fertilizers. They can’t afford those things. And it just runs the soil down. So they’re   (7)  .”
He estimates that up to two billion dollars worth of nitrogen,   (8)   is lost from African soil each year.
The scientist says the word perenniation defines three systems that are already used in Africa. The oldest of the three is called evergreen agriculture. This is where farmers plant trees with their crops. John Reganold says farmers in Africa have been doing this for sixty years, but it seems to be growing in popularity.
The method is   (9)   in countries such as Niger, Burkina Faso, Malawi and Zambia. The trees are planted among maize, millet or sorghum crops. They not only add nitrogen to the soil through their roots, but also through their leaves when they fall off and break down. At other times of the year, the trees can protect plants from strong sunlight.
John Reganold says he knows of one woman who has had great success with perenniation.
JOHN REGANOLD: “She’s a grandmother in her fifties. Her name is Rhoda Mang’yana and she started using this system about twenty years ago. And her yields initially were about a ton of maize.             (10)            . Four times what she was getting.”
Mr. Reganold was one of three researchers who wrote a report about perenniation. It was published in the journal Nature.
上期活动答案：
1.        Estimated
2.        Mortality
3.        Informatics
4.        Areas
5.        Developed
6.        causes of death
7.        pleased with
8.        the rate of decline
9.        child survival
10.        there’s a lot of work that remains to be done