在线词典,在线翻译

揭秘蜜蜂数量减少的原因

所属:听力板块 阅读:3584 次 评论:0 条 [我要评论]  [+我要收藏]

小编摘要:蜜蜂每年为美国的农作物增加约180亿美元的价值,它们帮助果树、坚果和蔬菜授粉。不过,最近几年,美国和欧洲的蜜蜂群落在减少。科学家提出各种理论来解释这种所谓的蜂群衰竭失调现象。

揭秘蜜蜂数量减少的原因

 

Bees add an estimated eighteen billion dollars a year to the value of American crops. They pollinate flowers that become fruits, nuts and vegetables. But, in recent years, honeybee colonies in the United States and Europe have been shrinking. Scientists have proposed different theories to explain what is known as colony collapse disorder.

New research suggests that a commonly used group of insecticides could cause bees to have a hard time finding their way back to their hive.

The new research looks at the use of pesticides called neonicotinoids. They were first used in the nineteen nineties. They are now put on the seeds of many major crops around the world. The seedlings absorb the chemical as they grow.

That means farmers do not need to spray a whole field. Instead there is a little bit of insecticide inside each plant -- including the pollen and nectar that the bees want.

There is not enough pesticide to kill them. But the new research in the journal Science says it may harm them anyway.

Researchers stuck microchips to the backs of the bees. These chips recorded the bees' movements as they came and went from their hive.

The scientists fed some bees sugar water with a low dose of a neonicotinoid. The study found that these bees were about twice as likely not to return as other bees.

Mickael Henry from INRA, the French national agriculture research institute, says the bees basically get drunk.

MICKAEL HENRY: " Intoxicated honeybees with those small doses may just get lost and are not able to find their way back home."

For some crops around the world, wild pollinators like bumblebees are more important than honeybees. Dave Goulson at the University of Sterling in Britain worked on another study published in Science. He says the pesticides could help explain why bumblebee populations are also decreasing.

DAVE GOULSON: "There were eighty-five percent fewer queens produced when they'd been exposed to realistic field levels."

Bayer CropScience makes neonicotinoid pesticides. Company spokesman Jack Boyne disputed the findings.

JACK BOYNE: "Instead of dosing the animals at field-relevant concentrations as the authors intended, they instead dosed them at levels far greater than what would commonly be experienced in the field."

He also notes that researchers are studying other factors that could affect bee populations. These include parasites, diseases and stress caused by transporting beehives to farms.

Some European countries have banned the pesticides. And there are growing calls to ban them in the United States as well.

标签:voa special
3
2012-04-09 21:00 编辑:pliny
分享到:
关注海词微博:
发表评论:
表达一些您的想法吧!已有0条评论>>
登录,再发表评论
文明上网,理性发言!
您可能还感兴趣的文章:
  • [听力板块]为什么说精准农业是一项好投资?

    精准农业是谋划如何提高产量,以及从现有资源中获取更多回报的一种途径。它通常涉及到技术的运用。计算机制导的拖拉机就是富裕国家常见的一个例子。
  • [听力板块]补充每天所需维生素

    维生素(vitamin)是人和动物为维持正常的生理功能而必需从食物中获得的一类微量有机物质,在人体生长、代谢、发育过程中发挥着重要的作用。
>>精华推荐阅读
热门评论文章