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小昆虫本领大(Big ability of small insects)

2013-05-15 21:20
导读:六级英语作文范文,小昆虫本领大(Big ability of small insects)怎么写,格式要求,写法技巧,科教作文网展示的这篇文章是很好的参考:  think twice before you swat a fly or squash a bug: a new study says insects contribute more

  think twice before you swat a fly or squash a bug: a new study says insects contribute more than $57 billion (euro47 billion) a year to the u.s. economy.

  think twice before you swat a fly or squash a bug: a new study says insects contribute more than $57 billion (euro47 billion) a year to the u.s. economy.

  and that is a very conservative estimate, said john losey, a cornell university associate professor of entomology who conducted the study, published in the current issue of the journal bioscience.

  "most insects tirelessly perform functions that improve our environment and lives in ways that scientists are only beginning to understand,'' said losey, who wrote the study with mace vaughan of the portland, oregon-based xerces society for invertebrate conservation.

  there are more than 1 million named insect species _ and probably an equal number unidentified _ making them the most abundant life form on the planet.

  the study focused on four particular services that bugs provide, and what the cost would be if the insects were gone:

  nutrition for wildlife. the researchers looked at how much is spent annually on observing or hunting wildlife, and how much these animals depend on insects for food. value: $50 billion (euro41.3 billion).

  pest control. insects often prey on other insects. the researchers looked at the amount of damage done by pests, and the losses that would result if their predators disappeared. value: $4.5 billion (euro3.7 billion).

  pollination. the researchers looked at the value of crops that are insect-pollinated (not including crops pollinated by domesticated honeybees). value: $3 billion (euro2.5 billion).

  dung burial. if not for dung beetles, manure on grazing land would attract more flies and parasites that farmers would have to control. also, dung beetles help return nutrients to the soil. without them, farmers would have to spend more on fertilizer. value: $380 million (euro314 million).

  the study focused only on wild insects and did not count the value of commercially produced insect-derived products, such as honey and silk.

  lawrence abrahamson, an entomologist at the state university of new york, agreed the $57 billion (euro47 billion) figure is conservative.

  "most people think of insects and go yuck. they think about mosquitoes and flies. they don't realize just about everything in life is affected some way, somehow, by insects,'' he said.

  "小昆虫本领大"英语作文译文:

  当你挥动苍蝇拍想要打死一只苍蝇或臭虫时,最好三思而后行。因为一项最新的研究结果显示,昆虫每年给美国经济带来的贡献竟然超过了570亿美元之多。

  据美联社日前报道,这项研究的负责人、美国科内尔大学的昆虫学副教授约翰·罗赛对此表示,不仅如此,而且上述数字还是一个非常保守的估计。他说:“大部分昆虫都在不知疲倦地行使着改善人们生活环境的职责,而它们所用的这些方式科学家们才刚刚开始了解。”

  目前,有超过100万种已命名的昆虫种类,而且可能还有相同数量的未经确认的昆虫,这使它们成为地球上生活方式最为丰富多彩的物种。

  诸多好处 一一列举

  此项研究将重点放在了昆虫向人们提供的4种特殊服务以及如果这些小虫消失不见,人们在这些方面应该相应付出的花费上。

  1、野生动物的营养来源。研究人员对美国每年观察或捕猎野生动物花费多少,以及这些动物中有多少以昆虫作为食物来源进行了研究。研究得出的结论是,昆虫对美国经济的贡献价值为500亿美元。

  2、控制害虫。昆虫经常以其它昆虫为食。因此,研究人员对害虫造成的危害以及如果这些害虫的天敌消失,美国将要为此遭受的损失进行了分析研究。研究得出的结果是,昆虫对美国经济的贡献价值为45亿美元。

  3、授粉。研究人员还对那些由昆虫授粉的农作物(不包括那些由驯化蜜蜂授粉的农作物)的价值进行了估算。并由此得出结论,昆虫对美国经济的贡献价值为25亿美元。

  4、消化粪便。如果不是蜣螂(屎克螂)这种小昆虫在帮忙,那么在土地上施肥就会吸引更多的苍蝇和寄生虫,这样农民们就不得不想办法来解决这个问题。另外,屎克螂还有助于将营养物质重新输送回土壤。如果没有它们,辛勤劳作的农民们就要花费更多的钱来购买肥料。由此,研究人员得出的结论是,在这方面昆虫对美国经济的贡献价值为3.8亿美元。

  报道说,此项研究的对象仅仅为野生昆虫为美国社会创造的财富,并不包括诸如蜂蜜和丝绸等由昆虫带来的商业产品的价值。这项研究的具体结果发表在最近一期的《生物科学》杂志上。

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