久久亚洲国产成人影院-久久亚洲国产的中文-久久亚洲国产高清-久久亚洲国产精品-亚洲图片偷拍自拍-亚洲图色视频

  Home>News Center>China
       
 

Alien flora and fauna pose threat to capital
By Ma Chenguang (China Daily)
Updated: 2005-11-04 05:51

Officials and researchers based in Beijing are calling for an investigation of species from outside China that have been settling in the capital.

They must be properly documented to assess any possible negative impact on the environment and economy.

At present, 56 foreign species are known to be living in Beijing, with some dubbed "quite invasive," the Beijing Morning Post reported on Wednesday.

The newspaper said the alien flora and fauna include about 30 types of plants and more than 20 different animals.

Liu Quanru, an associate professor of life sciences at Beijing Normal University, told the newspaper that while these plants beautify the capital and some of the animals make delicious meals, the damage they may cause should not be forgotten.

There are no figures available to indicate the economic losses suffered by Beijing as a result of these uninvited guests, but national statistics show how destructive they can be.

According to Zhu Xiuyan, chief economist at the Ministry of Agriculture, more than 400 types of harmful alien plants cause annual losses of more than 57.4 billion yuan (US$7.1 billion) in the country's agriculture, forestry, animal husbandry and fishery industries.

Rhus typhina L, a type of tree that is prevalent in fields between the Fourth Ring Road and Fifth Ring Road, and Solanum rostratum or "buffalobur nightshade" with banana-shaped anthers on its flowers, have both been invading other plants' space.

Liu said they tend to absorb neighbours' nourishment due to their ability to spread even in barren places.

Amaranthus retroflexus L is a weed that is poisonous to some animals, while the weed Ambrosia tritida L threatens human health, the professor warned.

Though delicious, red crayfish, Ampullaria Crossean a type of mollusc and bullfrog are aggressive, grabbing the resources of other species.

Hyphantria Cunea, a type of moth known as "Fall Webworm," harms crops, Liu said.

Zhao Wenxia, an associate research fellow from the Chinese Academy of Forestry, told China Daily yesterday that scientific tests have shown "not all alien species are bad," citing some types of pine and locust trees that exist alongside other flora without damaging the environment.

"However, random spreading of unknown alien species to crop land or wild areas can be dangerous," she said.

Zhang Runzhi, a researcher at the Chinese Academy of Sciences, outlined measures that could help halt the random spread of harmful exotic species.

They include a pre-warning system for detecting invasive species, restrictions through quarantine and examination channels, eradication programmes and blockades, and a legal framework for forbidding improper imports or transport means with a view to quick detection.

(China Daily 11/04/2005 page3)



Folk dance competition in Guiyang
Taiwan performance in Hangzhou
Poor kids' strong desire for school
  Today's Top News     Top China News
 

Sino-Russian energy links to expand

 

   
 

Number of billionaires triples to 10

 

   
 

Olympic mascot to be revealed Nov 11

 

   
 

China plans 2007 space mission

 

   
 

North Korea nuclear talks set for next week

 

   
 

Henan gets it right in war on HIV/AIDS

 

   
  Disposable tableware poses health risk
   
  China, India to extend tariff cuts
   
  Olympic goods win licensing go-ahead
   
  Mine blast kills 17 in Shanxi
   
  Students may get a crack at US science books
   
  Capital int'l airport seeks expansion
   
 
  Go to Another Section  
 
 
  Story Tools  
   
  News Talk  
  It is time to prepare for Beijing - 2008  
Manufacturers, Exporters, Wholesalers - Global trade starts here.
Advertisement
         
主站蜘蛛池模板: 收集最新中文国产中文字幕 | 国产成人免费高清在线观看 | 一区三区三区不卡 | 免费一级毛片在线播放视频 | 国内自拍第1页 | 久草视频免费在线看 | 6080伦理久久亚洲精品 | 美国一级片在线观看 | 中文字幕一区二区三区精品 | 久久两性视频 | 成人综合在线视频 | 怡红院免费在线视频 | 欧美日韩精品一区二区三区视频在线 | 一级a级国产不卡毛片 | 91伊人久久| 欧美成人午夜毛片免费影院 | 亚洲精品一区二区三区美女 | 老司机一级片 | 波多野结衣在线免费视频 | 男女国产视频 | 国产精品久久久久影院 | 91精品一区二区三区在线播放 | 国产精品欧美亚洲韩国日本不卡 | 美国一级欧美三级 | a级午夜毛片免费一区二区 a级性生活视频 | 国产久草视频在线 | 亚洲精品在线网 | 免费三级毛片 | 国产成人综合洲欧美在线 | 99视频国产热精品视频 | 国产真实生活伦对白 | 日本三级网站在线观看 | 美女视频黄a视频免费全过程 | a国产精品 | 1024手机基地在线看手机 | 欧美成人欧美激情欧美风情 | 99er精品 | 日韩一级一欧美一级国产 | 一级a俄罗斯毛片免费 | 写真片福利视频在线播放 | 国产高清天干天天视频 |