北极熊在夏天需要节省小部分体能
文章来源:未知 文章作者:enread 发布时间:2015-07-21 06:49 字体: [ ]  进入论坛
(单词翻译:双击或拖选)
Polar bears are unlikely to physiologically1 compensate2 for extended food deprivation3 associated with the ongoing4 loss of sea ice, according to one-of-its-kind research conducted by University of Wyoming scientists and others, and published today in the journal Science. "We found that polar bears appear unable to meaningfully prolong their reliance on stored energy, confirming their vulnerability to lost hunting opportunities on the sea ice -- even as they surprised us by also exhibiting an unusual ability to minimize heat loss while swimming in Arctic waters," says John Whiteman, the UW doctoral student who led the project.
 
The loss of sea ice in the Arctic, which is outpacing predictions, has raised concern about the future of polar bears, leading to their listing as a globally threatened species under the U.S. Endangered Species Act in 2008. The bears depend on hunting seals on the surface of the sea ice over the continental5 shelf, most successfully from April to July. In parts of the polar bears' range, the lengthening6 period of sea ice retreat from shelf waters -- caused by increasing temperatures -- can reduce their opportunities to hunt seals, leading to declines in bear nutritional7 condition.
 
Some earlier research suggested that polar bears could, at least partially8, compensate for longer summer food deprivation by entering a state of lowered activity and reduced metabolic9 rate similar to winter hibernation10 -- a so-called "walking hibernation." But the new research shows that the summer activity and body temperature of bears on shore and on ice were typical of fasting, non-hibernating mammals, with little indication of "walking hibernation."
 
Whiteman and his colleagues concluded in the Science publication: "This suggests that bears are unlikely to avoid deleterious declines in body condition, and ultimately survival, that are expected with continued ice loss and lengthening of the ice-melt period."
 
The researchers reached that conclusion by capturing more than two dozen polar bears, implanting temperature loggers and tracking their subsequent movements on shore and on ice in the Arctic Ocean's Beaufort Sea, north of Alaska and Canada, during 2008-2010. The unprecedented11 effort, logistically supported by the U.S. Geological Survey (USGS) and funded by the National Science Foundation, USGS, U.S. Fish and Wildlife Service (USFWS), as well as the Environmental Protection Agency, required the assistance of numerous personnel, multiple helicopters and deployment12 of the U.S. Coast Guard ice-breaker, the Polar Sea.


点击收听单词发音收听单词发音  

1 physiologically QNfx3     
ad.生理上,在生理学上
参考例句:
  • Therefore, the liver and gallbladder cannot be completely separated physiologically and pathologically. 因此,肝胆在生理和病理上不能完全分离。
  • Therefore, the liver and gallbladder are closely related physiologically and pathologically. 因此,肝胆在生理和病理上紧密联系。
2 compensate AXky7     
vt.补偿,赔偿;酬报 vi.弥补;补偿;抵消
参考例句:
  • She used her good looks to compensate her lack of intelligence. 她利用她漂亮的外表来弥补智力的不足。
  • Nothing can compensate for the loss of one's health. 一个人失去了键康是不可弥补的。
3 deprivation e9Uy7     
n.匮乏;丧失;夺去,贫困
参考例句:
  • Many studies make it clear that sleep deprivation is dangerous.多实验都证实了睡眠被剥夺是危险的。
  • Missing the holiday was a great deprivation.错过假日是极大的损失。
4 ongoing 6RvzT     
adj.进行中的,前进的
参考例句:
  • The problem is ongoing.这个问题尚未解决。
  • The issues raised in the report relate directly to Age Concern's ongoing work in this area.报告中提出的问题与“关心老人”组织在这方面正在做的工作有直接的关系。
5 continental Zazyk     
adj.大陆的,大陆性的,欧洲大陆的
参考例句:
  • A continental climate is different from an insular one.大陆性气候不同于岛屿气候。
  • The most ancient parts of the continental crust are 4000 million years old.大陆地壳最古老的部分有40亿年历史。
6 lengthening c18724c879afa98537e13552d14a5b53     
(时间或空间)延长,伸长( lengthen的现在分词 ); 加长
参考例句:
  • The evening shadows were lengthening. 残阳下的影子越拉越长。
  • The shadows are lengthening for me. 我的影子越来越长了。 来自演讲部分
7 nutritional 4HRxN     
adj.营养的,滋养的
参考例句:
  • A diet lacking in nutritional value will not keep a person healthy.缺乏营养价值的饮食不能维持人的健康。
  • The labels on food products give a lot of information about their nutritional content.食品上的标签提供很多关于营养成分的信息。
8 partially yL7xm     
adv.部分地,从某些方面讲
参考例句:
  • The door was partially concealed by the drapes.门有一部分被门帘遮住了。
  • The police managed to restore calm and the curfew was partially lifted.警方设法恢复了平静,宵禁部分解除。
9 metabolic 2R4z1     
adj.新陈代谢的
参考例句:
  • Impressive metabolic alternations have been undergone during embryogenesis.在胚胎发生期间经历了深刻的代谢变化。
  • A number of intoxicants are associated with metabolic acidosis.许多毒性物质可引起代谢性酸中毒。
10 hibernation cdjxK     
n.冬眠
参考例句:
  • Bears wake up in the spring after a winter of hibernation.熊经过一个冬天的冬眠后在春季苏醒。
  • The tortoise spends the winter months in hibernation.乌龟在冬眠中度过寒冬季节。
11 unprecedented 7gSyJ     
adj.无前例的,新奇的
参考例句:
  • The air crash caused an unprecedented number of deaths.这次空难的死亡人数是空前的。
  • A flood of this sort is really unprecedented.这样大的洪水真是十年九不遇。
12 deployment 06e5c0d0f9eabd9525e5f9dc4f6f37cf     
n. 部署,展开
参考例句:
  • He has inquired out the deployment of the enemy troops. 他已查出敌军的兵力部署情况。
  • Quality function deployment (QFD) is a widely used customer-driven quality, design and manufacturing management tool. 质量功能展开(quality function deployment,QFD)是一个广泛应用的顾客需求驱动的设计、制造和质量管理工具。
TAG标签: energy ice bears
发表评论
请自觉遵守互联网相关的政策法规,严禁发布色情、暴力、反动的言论。
评价:
表情:
验证码:点击我更换图片