VOA慢速英语 2009 016a

This is the VOA Special English Agriculture Report.

Grasslands¹ need time to rest when cattle and other animals feed on them. Moving animals from one area of pasture to another can provide the time needed for new growth. This is called rotational² grazing, and we received a question from Zhang Guohui in China about how it works.

Experts say rotational grazing is good for the land and the animals, and it can save money. This form of grazing can reduce the need for pesticide³ treatments by reducing the growth of weeds. And it can limit the need for chemical fertilizers by letting animal waste do the job of natural fertilizer. Rotational grazing can even help prevent wildfires by keeping grasslands in good condition.

Letting animals feed continually and intensively in the same grazing areas can require costly⁴ replanting. Animals eat the most desirable growth first. When that keeps happening, the roots do not have enough time to recover. As a result, less desirable plants may replace them.

Intensively used grasslands are also harmed as the soil is continually crushed under the weight of heavy animals. And the animals usually avoid their own waste, so that reduces the amount of good grazing space even more.

Experts say that while rotational grazing can save money over time, it also requires planning. And that starts with a good map to mark fences, water supplies and grazing areas.

Changing methods of grazing also requires time. Farmers may want to put up electric fences to enclose grazing areas, called paddocks. The paddocks will need water. Some farmers design a path for animals from different paddocks to drink from a common watering place.

Farmers can start rotational grazing by removing animals from a pasture when the grass is eaten to less than five centimeters. The pasture is then kept empty until the grass grows to more than fifteen centimeters high.

Experts say sheep and goats may require special preparations. They may need stronger fences than other animals. And while they eat the grass, they may need guard animals to protect them from animals that would like to eat them.

And that's the VOA Special English Agriculture Report, written by Jerilyn Watson. Transcripts⁵, MP3s and podcasts of our reports are at voaspecialenglish.com. To write to us, write to [email protected]. And please include your name and where you are. I'm Steve Ember.

1 grasslands   

n.草原，牧场( grassland的名词复数 )

参考例句：

• 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》

2 rotational   

adj.回转的，轮流的

参考例句：

• A synchronous motor drives the measuring bob at a constant rotational speed.同步马达驱动测锤以恒速旋转。
• With some limitations,this is true also of rotational degrees of freedom.在某些限定条件下，这一说法对转动自由度也成立。

3 pesticide   

n.杀虫剂，农药

参考例句：

• The pesticide was spread over the vegetable plot.菜田里撒上了农药。
• This pesticide is diluted with water and applied directly to the fields.这种杀虫剂用水稀释后直接施用在田里。

4 costly   

adj.昂贵的，价值高的，豪华的

参考例句：

• It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
• This dictionary is very useful,only it is a bit costly.这本词典很有用，左不过贵了些。

5 transcripts   

n.抄本（ transcript的名词复数 ）；转写本；文字本；副本

参考例句：

• Like mRNA, both tRNA and rRNA are transcripts of chromosomal DNA. tRNA及rRNA同mRNA一样，都是染色体DNA的转录产物。 来自辞典例句
• You can't take the transfer students'exam without your transcripts. 没有成绩证明书，你就不能参加转学考试。 来自辞典例句