2015复习正是强化复习阶段,在考研英语中占了40分,所以考研英语阅读是英语科目中重要的一项。名师老师曾建议过考研生需要坚持每天泛读10-15分钟的英文原刊。强烈推荐了杂志《经济学人》.杂志中的文章也是考研英语的主要材料来源.希望考研考生认真阅读,快速提高考研英语阅读水平。 Bees and insecticides 蜜蜂和杀虫剂 Subtle poison 慢性毒药 Evidence is growing that commonly used pesticides,even when employed carefully, are bad for bees 证据逐步表明,即使小心地喷施普通杀虫剂,也会对蜜蜂构成危害 IN THE winter of 2006 beekeepers in America noticed something oddlots of their hives weredying for no obvious reason. 2006年冬,美国养蜂人注意到奇怪的现象,他们的蜜蜂成批死掉,原因不明。 As the months passed, reports of similar phenomena began coming in from their Europeancounterparts. 几个月后,类似的现象也出现在欧洲同行的报告上。 Mystified scientists coined the label colony collapse disorderto describe what washappening. 困惑的科学家们给这个现象贴上了蜂群衰竭失调的标签。 Since then, much brow-sweat has been expended trying to work out just what CCD really is. 自那时起,为揭开CCD的面纱,人们不知道多少次抹去额头的汗水。 Dying bees are a problem, and not just for apiarists. 蜜蜂之死不仅令养蜂家头痛。 Bees pollinate many of the world s cropsa service estimated to be worth 15 billion a yearin America alone. 蜜蜂给世界上的很多庄稼授粉,仅在美国,这种服务每年价值150亿美元。 And there is no shortage of theories to explain the insects decline,Climate change, habitatdestruction, a paralysing virus, fungal infection and even a plague of parasitic mites haveall been proposed. 尽管对蜜蜂数量下降的原因提出了形形色色的理论,如气候变化、栖息地遭破坏、麻痹病毒、霉菌感染,甚至还有寄生虫肆虐。 But one of the leading ideas is that the bees are suffering from the effects of neonicotinoids, aclass of commonly used pesticides, introduced in the 1990s, which are toxic to insects butmuch less so to mammals. 但其中一个主导观点是蜜蜂正在遭受新烟碱的侵害,二十世纪九十年代人们引入这种杀虫剂,它对昆虫有毒,但对哺乳动物的毒性较小,使用范围广泛。 Two papers published this week in Science lend weight to this idea. 本期科学杂志刊登的两篇论文证实了这种观点。 The first, from a group led by Penelope Whitehorn and David Goulson of the University ofStirling, in Britain, examined the effects these insecticides have on bumblebees, which areclosely related to honeybees. 第一篇出自英国斯特林大学Penelope Whitehorn 和 David Goulson 指导的团队,他们检验了这些杀虫剂给大黄蜂带来的影响,大黄蜂和蜜蜂的关系密切。 Bumblebees are less studied than their honeybee cousins, but they also pollinate manycommonly eaten crops, including strawberries, raspberries and runner beans. 和同宗的蜜蜂比起来,对大黄蜂的研究要少一些。但它们给很多可食作物传粉,如草莓、树莓和红花菜豆。 The two researchers and their colleagues raised 75 bumblebee colonies in their laboratory. 两位研究人员和同事们在实验室饲养了七十五个大黄蜂蜂群。 They exposed some, via contaminated pollen and sugar water, to high doses ofimidacloprid, a type of neonicotinoid insecticide. 他们用受污染的花粉、糖水将一些蜂群暴露在高剂量吡虫啉的环境里, Others were exposed to low doses, or to no dose at all. 一些蜂群暴露在低剂量杀虫剂的环境里,或者不加一点杀虫剂。 Then, after two weeks of this treatment, the colonies were taken into the outside world andleft there for six weeks, to see how the bees did. 接着经过两周的处理,把这些蜂群放在室外六周,观察蜂的行动。 All of the doses of imidacloprid, both high and low, that Dr Whitehorn gave her bees weresublethalin other words, insufficient to kill the insects outright. 使用吡虫啉的蜂群,无论剂量大小,Whitehorn博士把亚致死量用在她的蜜蜂上,换句话说,不足以彻底杀死昆虫。 Firms that produce pesticides, and the authorities that regulate them, are aware of theimportance of bees to food production, and new products must be tested to make sure theyare not fatal to helpful insects. 杀虫剂生产厂家和管理他们的机构意识到蜜蜂对食品生产的重要性,新产品要经过检测,保证它们不会对有益的昆虫造成致命伤害。 But Dr Whitehorn found that even non-lethal doses of pesticide were bad for bees. 但Whitehorn博士发现即使非致命性杀虫剂也会对蜜蜂有害。 Both the high-dose and the low-dose colonies grew more slowly than the undosed ones,gaining 8-12% less weight on average. 受到高剂量和低剂量杀虫剂影响的蜂群和没有受杀虫剂影响的同类比起来长得要慢。体重平均降低8-12%。 More importantly, the pesticides drastically inhibited the production of queens, which areneeded to establish new nests each spring. 最重要的是,杀虫剂强烈地影响到春季筑造新巢所需的蚁后的生产。 The undosed colonies produced 13.7 queens, on average. 未受杀虫剂影响的蜂群产生13.7个蚁后。 Those given a small dose of insecticide produced two. 受低剂量影响的蜂群产生两个, Those given a high dose produced just 1.4. 受高剂量杀虫剂影响的蜂群产生1.4个。 Worryingly, even colonies given the high dose may have got off lightly compared with theirwild brethren. 令人忧心的是,即便受高剂量杀虫剂影响的蜂群可能要比它们在野外的同伴受到的危害低一些。
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