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: 亚洲成人免费观看 | 欧美在线播放视频 | 国产一区二区精品久久凹凸 | 一区二区三区视频 | 91无套极品外围在线播放 | 国产免费人视频在线观看免费 | 最新国产一区二区精品久久 | 日本一区二区三区四区不卡 | 在线视频区 | 手机看黄av免费网址 | 国产精品理论片在线观看 | 久色视频在线观看 | 久久久99精品免费观看精品 | 日韩一级片在线播放 | 免费一级做a爰片性色毛片 免费一极毛片 | 久久狠狠色狠狠色综合 | 中文字幕 亚洲 一区二区三区 | 一个人看的免费高清视频日本 | 国内精品久久久久不卡 | 欧美日韩另类视频 | 中文字幕亚洲一区二区va在线 | 国产最爽的乱淫视频国语对 | 91成人啪国产啪永久地址 | 欧美14videosex性欧美成人 | 欧美亚洲精品在线 | 欧美在线1 | 99久久国产免费福利 | 欧美精品久久久久久久影视 | 欧美精选在线 | 欧美日韩精品一区二区三区高清视频 | 国产成人a在一区线观看高清 | 91九色视频无限观看免费 | 久久精品国产99久久久 | 欧美日韩国产一区二区三区播放 | 欧美日韩另类综合 | 久久毛片网站 | 一区二区三区四区视频在线 | 国产高清成人mv在线观看 | 精品国产一区二区三区www | 中国一级特黄视频 | 大狠狠大臿蕉香蕉大视频 |