秃鹰对生态环境的重要性
文章来源:未知 文章作者:enread 发布时间:2016-05-06 08:22 字体: [ ]  进入论坛
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Vultures. Cartoon characters in parched1 deserts often wish them to disappear, since circling vultures are a stereotypical2 harbinger of death. But, joking aside, vultures in some parts of the world are in danger of disappearing. And according to a new report from University of Utah biologists, such a loss would have serious consequences for ecosystems3 and human populations alike. The primary threat to vultures, according to the report published today in Biological Conservation, is the presence of toxins4 in the carrion5 they consume. On many continents, vultures are the unfortunate victims of poisoned carcasses -- especially impactful because dozens -- or even hundreds -- of vultures can feast on a single carcass. Populations of most vulture species around the world are now either declining or on the brink6 of extinction7.
 
Losses of vultures can allow other scavengers to flourish, according to biologists Evan Buechley and Ça?an ?ekercio?lu. Proliferation of such scavengers could bring bacteria and viruses from carcasses into human cities.
 
Risk factors for decline
 
In 2004, ?ekercio?lu published a study examining the respective extinction risks of all bird species throughout the world. He noted8 then that vultures represented the single most threatened group of birds. Now, more than a decade later, Buechley and ?ekercio?lu have examined factors affecting the extinction risk of more than 100 bird species, including 22 species of vultures, which eat carrion exclusively, and other scavenging birds that have broader diets.
 
Their results suggest several inherent ecological9 traits that likely contribute to vultures' extinction risk, including their large body masses, slow reproductive rates and highly specialized10 diets. The greatest external threat to vultures, however, is poisoning.


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1 parched 2mbzMK     
adj.焦干的;极渴的;v.(使)焦干
参考例句:
  • Hot winds parched the crops.热风使庄稼干透了。
  • The land in this region is rather dry and parched.这片土地十分干燥。
2 stereotypical af5b561e94abd66f688fbfcccaffdce3     
n.常规
参考例句:
  • Personas should be typical and believable, but not stereotypical. 人物角色应该是典型和可信赖的,但不是一成不变的。 来自About Face 3交互设计精髓
  • Anything could be stereotypical, so I guess it could be criticism. 任何东西都可以变的老套,所以我猜那就是一种批评。 来自互联网
3 ecosystems 94cb0e40a815bea1157ac8aab9a5380d     
n.生态系统( ecosystem的名词复数 )
参考例句:
  • There are highly sensitive and delicately balanced ecosystems in the forest. 森林里有高度敏感、灵敏平衡的各种生态系统。 来自《简明英汉词典》
  • Madagascar's ecosystems range from rainforest to semi-desert. 马达加斯加生态系统类型多样,从雨林到半荒漠等不一而足。 来自辞典例句
4 toxins 18c3f40d432ba8dc33bad8fb82873ea8     
n.毒素( toxin的名词复数 )
参考例句:
  • The seas have been used as a receptacle for a range of industrial toxins. 海洋成了各种有毒工业废料的大容器。
  • Most toxins are naturally excreted from the body. 大部分毒素被自然排出体外。 来自《简明英汉词典》
5 carrion gXFzu     
n.腐肉
参考例句:
  • A crow of bloodthirsty ants is attracted by the carrion.一群嗜血的蚂蚁被腐肉所吸引。
  • Vultures usually feed on carrion or roadkill.兀鹫通常以腐肉和公路上的死伤动物为食。
6 brink OWazM     
n.(悬崖、河流等的)边缘,边沿
参考例句:
  • The tree grew on the brink of the cliff.那棵树生长在峭壁的边缘。
  • The two countries were poised on the brink of war.这两个国家处于交战的边缘。
7 extinction sPwzP     
n.熄灭,消亡,消灭,灭绝,绝种
参考例句:
  • The plant is now in danger of extinction.这种植物现在有绝种的危险。
  • The island's way of life is doomed to extinction.这个岛上的生活方式注定要消失。
8 noted 5n4zXc     
adj.著名的,知名的
参考例句:
  • The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
  • Jim is noted for arriving late for work.吉姆上班迟到出了名。
9 ecological IrRxX     
adj.生态的,生态学的
参考例句:
  • The region has been declared an ecological disaster zone.这个地区已经宣布为生态灾难区。
  • Each animal has its ecological niche.每种动物都有自己的生态位.
10 specialized Chuzwe     
adj.专门的,专业化的
参考例句:
  • There are many specialized agencies in the United Nations.联合国有许多专门机构。
  • These tools are very specialized.这些是专用工具。
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