听力首页 听力教程 VOA慢速 英语歌曲 外语下载 英语小说 英语词典 在线背单词 听力论坛 韩语学习
听力专题 英语教材 VOA标准 英语动画 英语考试 资源技巧 英语翻译 单词连连看 听力家园 德语学习
听力搜索 英语导读 BBC英语 英语视频 英语电台 英语QQ群 外语歌曲   英语游戏 英语网刊 日语学习
当前位置: 英语听力论坛 » 【每日英语新闻】 » 气候变化加速了害虫的扩散
返回列表 发帖

气候变化加速了害虫的扩散

Climate change is helping pests and diseases that attack crops to spread around the world, a study suggests.

研究发现,气候变化助长了农作物害虫和疾病的全球蔓延。

Researchers from the universities of Exeter and Oxford have found crop pests are moving at an average of 3km (two miles) a year.

The team said they were heading towards the north and south poles, and were establishing in areas that were once too cold for them to live in.

The research is published in the journal Nature Climate Change.

Currently, it is estimated that between 10% and 16% of the world's crops are lost to disease outbreaks. The researchers warn that rising global temperatures could make the problem worse.

Dr Dan Bebber, the lead author of the study from the University of Exeter, said: "Global food security is one of the major challenges we are going to face over the next few decades.

"We really don't want to be losing any more of our crops than is absolutely necessary to pests and pathogens."

Trade transport

To investigate the problem, the researchers looked at the records of 612 crop pests and pathogens from around the world that had been collected over the past 50 years.

These included fungi, such as wheat rust, which is devastating harvests in Africa, the Middle East and Asia; insects like the mountain pine beetle that is destroying trees in the US; as well as bacteria, viruses and microscopic nematode(线虫) worms.

Each organism's distribution was different - some butterflies and insects were shifting quickly, at about 20km a year; other bacterium species had hardly moved. On average, however, the pests had been spreading by 3km each year since 1960.

"We detect a shift in their distribution away form the equator and towards the poles," explained Dr Bebber,

The researchers believe that the global trade in crops is mainly responsible for the movement of pests and pathogens from country to country.

However, the organisms can only take hold in new areas if the conditions are suitable, and the researchers believe that warming temperatures have enabled the creature to survive at higher latitudes.

Dr Bebber said: "The most convincing hypothesis is that global warming has caused this shift.

"One example is the Colorado potato beetle. Warming appears to have allowed it to move northwards through Europe to into Finland and Norway where the cold winters would normally knock the beetle back."

The researchers said that better information about where the pests and pathogens were and where they were moving was needed to fully assess the scale of the problem.

"We also need to protect our borders, we have to quarantine plants to reduce the chances that pests and pathogens are able to get into our agricultural systems," added Dr Bebber.
更多英语新闻

so the reason is humankind

TOP

Although I look very hard...
You were laborious.

TOP

返回列表