The government-run command post in Tunis is staffed around the clock by military personnel, meteorologists and civilians. On the wall are maps, crisscrossed with brightly colors arrows that painstakingly track the fearsome path of the enemy.
What kind of invader gives rise to such high-level monitoring? Not man, not beast, but the lowly desert locust.(蝗虫) In recent months, billions of the 3-inch-long winged warriors have descended on Algeria, Libya, Morocco and Tunisia, blackening the sky and eating up crops and vegetation. The insect invasion, the worst in 30 years, is already creating great destruction in the Middle East and is now treating southern Europe. The current crisis began in late 1985 near the Red Sea. Unusually rainy weather moistened the sands of the Sudan, making them ideal breeding grounds for the locust, which lays its eggs in the earth. The insect onslaught threatens to create yet another African famine. Each locust can eat its weight (not quite a tenth of an ounce) in vegetation every 24 hours. A good-size swarm of 50 billion insects eats up 100,000 tons of grass, trees and crops in a single night.
All ﹩150 million may be needed this year. The U.S. has provided two spraying planes and about 50,000 gal. of pesticide. The European Community has donated ﹩3.8 million in aid and the Soviet Union, Canada, Japan and China have provided chemical-spraying aircraft to help wipe out the pests. But relief efforts are hampered by the relative mildness of approved pesticides, which quickly lose their deadly punch and require frequent replications. The most effective locust killer dieldrin has been linked to cancer and is banned by many Western countries and some of the affected African nations. More then 5 million acres have been dusted with locust-killing chemicals; another 5 million will be treated by the end of June.
On May 30, representatives of Tunisia, Algeria, Libya, Morocco and Mauritania will meet in Algiers to discuss tactics to wipe out the ravenous swarms. The move is an important step, but whatever plan is devised, the locust plague promised to get worse before the insects can be brought under control.
雅思听力笔记:四大特点
雅思听力笔记:搭配题
雅思听力笔记:基本要求
雅思听力高分要诀:语感与词汇量
雅思听力笔记:填空题
雅思听力:新生报到场景详细解析(复习建议)
雅思听力笔记:技巧训练-门牌号、数量的分位计数
考生必看:雅思听力考试租房场景讲解
雅思听力笔记:基本情况
雅思听力:课题研究场景详细解析(场景解析)
雅思听力:租房场景详细解析(常用词汇)
雅思听力笔记:个人信息表格
雅思听力笔记:图画题
雅思听力笔记:次序混乱、数字计算题、推理归纳题
雅思听力笔记:做题原则
雅思听力笔记:技巧训练-电话号码
雅思听力:课题研究场景详细解析(实例解析-填空题)
雅思听力:新生报到场景详细解析(常用词汇-选课)
雅思听力笔记:应试策略
雅思听力环保场景词汇总结
雅思听力:新生报到场景详细解析(常用词汇-数学)
雅思听力笔记:问答题
雅思听力笔记:常考场景
雅思听力笔记:技巧训练-时间
雅思听力笔记:基本解题思路
雅思听力:课题研究场景详细解析(相关词汇)
雅思听力笔记:技巧训练-计量和货币单位
雅思听力:课题研究场景详细解析(实例解析-问答题)
雅思听力笔记:学习方法
雅思听力笔记:需要注意的问题
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