英语听力：自然百科 西撒哈拉的列车

 An iron ore（铁矿)train operating across the northwest African nation of Mauritania(毛里塔尼亚) forms a striking image sneaking¹ its way through the Sahara desert. This desert train has had to be adapted to suit the harsh conditions that make it one-of-a-kind railway service.

 

“If we consider the train with all the locomotives(火车头) at the front, we have the longest and heaviest train in the world. That's for sure.”

 

 But it is the modifications² to suit local conditions that make it a truly unique railway. The train, in operation since 1963, begins its 700-kilometer journey deep in the Sahara desert in the mining town of Zouérat. Here iron ores are loaded onto the approximately 210 wagons⁴. 6 trains are operating both directions everyday between Zouérat and the port city of Nouadhibou. With temperatures reaching and sometimes exceeding 122 degrees Fahrenheit⁵， as well as problems associated with the sand, the train services had to adapt.

 

 “There's a technique used to fix the dune(沙丘) problem. After bulldozing(轧平) the dunes⁶, dead palm tree branches are planted into the sand dunes, making the dunes stable. After that, the dunes don't move any more. And we don't have a problem with sand drifting onto the railway tracks any more.”

 

The railway service also uses a second system-- sand ploughs（铲沙机), based on snow ploughs used on North American trains, can clear sand that drifts onto the standard gauge⁷ tracks.

 

Another challenge with this desert train is preventing sand from entering the General Motor's locomotive engines. In the diesel-electric(柴油电动的)locomotives first used here in 1982, sand quickly worked its way into the engines and destroyed them. As a result, the National Mining Industry Company, working with General Motors, devised a filtration system using an additional 36 filtering units per locomotive.

 

“Since we installed this extra filtration system, the problems with filtering the sand from the motors have been eliminated.”

 

While the train service is primarily for the transport of iron ore, there are limited passenger facilities, too.

“People take the train because it's cheaper than traveling by vehicle; however, we don't enjoy it because it's uncomfortable. There's a lot of dust, the wagon³ is in poor condition, and it's not clean.”

 

According to the National Mining Industry Company, the iron ore sales accounts for 40% of Mauritania's total exports. It's no surprise that every effort is made to ensure a reliable train service through the extreme conditions of the Sahara desert.

1 sneaking   

a.秘密的，不公开的

参考例句：

• She had always had a sneaking affection for him. 以前她一直暗暗倾心于他。
• She ducked the interviewers by sneaking out the back door. 她从后门偷偷溜走，躲开采访者。

2 modifications   

n.缓和( modification的名词复数 )；限制；更改；改变

参考例句：

• The engine was pulled apart for modifications and then reassembled. 发动机被拆开改型，然后再组装起来。 来自《简明英汉词典》
• The original plan had undergone fairly extensive modifications. 原计划已经作了相当大的修改。 来自《简明英汉词典》

3 wagon   

n.四轮马车，手推车，面包车；无盖运货列车

参考例句：

• We have to fork the hay into the wagon.我们得把干草用叉子挑进马车里去。
• The muddy road bemired the wagon.马车陷入了泥泞的道路。

4 wagons   

n.四轮的运货马车( wagon的名词复数 )；铁路货车；小手推车

参考例句：

• The wagons were hauled by horses. 那些货车是马拉的。
• They drew their wagons into a laager and set up camp. 他们把马车围成一圈扎起营地。

5 Fahrenheit   

n./adj.华氏温度；华氏温度计(的)

参考例句：

• He was asked for the boiling point of water in Fahrenheit.他被问到水的沸点是华氏多少度。
• The thermometer reads 80 degrees Fahrenheit.寒暑表指出华氏80度。

6 dunes   

沙丘( dune的名词复数 )

参考例句：

• The boy galloped over the dunes barefoot. 那男孩光着脚在沙丘间飞跑。
• Dragging the fully laden boat across the sand dunes was no mean feat. 将满载货物的船拖过沙丘是一件了不起的事。

7 gauge   

v.精确计量；估计；n.标准度量；计量器

参考例句：

• Can you gauge what her reaction is likely to be?你能揣测她的反应可能是什么吗？
• It's difficult to gauge one's character.要判断一个人的品格是很困难的。