首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
考研
Across the western United States alone, trout(a kind of fish)fishing generates hundreds of millions of dollars annually. But tro
Across the western United States alone, trout(a kind of fish)fishing generates hundreds of millions of dollars annually. But tro
admin
2015-03-25
28
问题
Across the western United States alone, trout(a kind of fish)fishing generates hundreds of millions of dollars annually. But trout habitat will likely be cut in half by 2080 due to warming rivers and altered patterns of flooding, according to a large study published online in the Proceedings of the National Academy of Sciences, " It’s fairly shocking to us, as biologists," says co-author Kurt Fausch of Colorado State University, Fort Collins. This is not a case of winners and losers; the four species examined by the team are all likely to decline to varying degrees.
By running several climate models and plugging in data on habitat characteristics and fish present at 9,890 locations in the Rocky Mountains and Great Basin, the team of scientists created predictions for trout habitat across more than 1 million square kilometers of the western United States. They factored physical aspects of habitat—water temperature, patterns of flooding—as well as competition among species. Here’s what the study concludes about the future of trout:
Introduced beginning in the 1800s for fishing, rainbow trout live in larger rivers than do the other species. They typically grow up to 110 centimeters long and are relatively easy to catch. Increases in water temperature will restrict their range, but rainbow trout
dodge a bullet
. Climate change will mean more frequent and intense winter floods, which can scour away eggs laid in the fall, but rainbow trout spawn in the spring. The size of their habitat is predicted to decline by 35%.
Smaller than rainbow trout, Brown trout are the most temperature tolerant among the four species and like warmer temperatures. They have the ill fortune to spawn in the fall, so the increased flooding will make many streams inhospitable. Their habitat is predicted to decline by 48%.
As to Cutthroat trout, the range of these native fish has already shrunk by more than 85% due to competition from introduced species. Two subspecies have already gone extinct. Warming temperatures and continued competition primarily from rainbow trout are predicted to reduce suitable habitat by a further 58%.
Compared with the other species, brook trout are the biggest losers in 2080. Because they spawn in the fall, the increase in winter flooding is expected to reduce their suitable habitat by 77%—a surprising amount given their success at invading new habitat. "I did not expect brook trout to decline so much," says co-author Seth Wenger, a biologist with Trout Unlimited, a conservation organization in Boise.
Frank Rahel, a fish ecologist at the University of Wyoming in Laramie, who was not involved with the study, says the findings help paint the big picture for trout this century. "They’re very sobering results that will catch people’s attention," he says. Not much can be done to reduce the impact of winter floods, but managers already try to keep streams cooler by planting trees and shrubs.
The phrase "dodge a bullet"(Line 3, Para.3)most probably means
选项
A、escaping successfully from a hunter’s shooting.
B、being lucky and escaping the fate of destruction.
C、having the ability to run away from a bullet.
D、dying in a large number due to shooting.
答案
B
解析
语义理解题。根据题干提示定位到第三段。该段介绍虹鳟鱼的生存情况,指出虽然水温增高和冬季洪水会对其生存造成威胁,但幸运的是虹鳟鱼在春天产卵,因此受冬季洪水的影响较小,这可使它可以逃过一劫。根据上下文的转折关系可判断,[B]与原文意思相符,是正确答案。而[A]“成功躲避猎人射杀”,[C]“具有躲避子弹的能力”均是望文生义,故排除。
转载请注明原文地址:https://kaotiyun.com/show/hL74777K
0
考研英语一
相关试题推荐
ThepopulationoftheUnitedStatesisonly6%theworld’spopulation,butAmericans(1)_____onethirdofalltheenergy(2)___
Manypeopleconsiderthewideruseofbiofuelsapromisingwayofreducingtheamountofsurpluscarbondioxide(C02)beingpump
Whenwomendobecomemanagers,dotheybringadifferentstyleanddifferentskillstothejob?Aretheybetter,orworse,manag
Whenwomendobecomemanagers,dotheybringadifferentstyleanddifferentskillstothejob?Aretheybetter,orworse,manag
Whenwomendobecomemanagers,dotheybringadifferentstyleanddifferentskillstothejob?Aretheybetter,orworse,manag
Notlongago,thequestionwhethertheDragonBoatFestivalshouldbeestablishedbythegovernmentasanationalholidayoncec
TheSupremeCourt’sdecisionsonphysician-assistedsuicidecarryimportantimplicationsforhowmedicineseekstorelievedying
Cancerisataleoftwosetsofgeneticcode,yourownandyourtumor’s—andtracingtheuniqueareasofdamagemakesforawayt
Hurlingbrickbatsatbankersisapopularpastime.The"OccupyWallStreet"movementanditsvariousbranchescomplainthatavi
随机试题
钢回火的加热温度在A1线以下,因此,回火过程中无组织变化。()
不属于乳酸代谢的生物学意义的是
健康教育与健康促进计划设计的全过程,包括的三个组成部分是
马某与田某1999年结婚,因感情不和于2004年协议离婚。共同财产已经分割完毕,孩子归田某抚养,由马某每月支付2000元抚养费。后因与田某在抚养费上发生争执,田某声称要举报其偷税漏税行为。2007年6月,马某收到税务部门要求其补缴2002、2003年的个人
某演员收到演出费20万元,则演出费收入应纳个人所得税额为( )元。
勤俭持家是社会主义基本道德规范的基本内容。()
《凡尔登条约》
罗马法复兴时期出现的以研究和恢复罗马法为核心的法学流派是()。
Patronswhomakeacontributiontothemuseum’sexpansionfundwillreceiveathank-youcardsigned______bythecurator.
ArecentcaseinAustraliashowshoweasilyfearcanfrustrateaninformant’sgoodintentions.InDecember,awomanwroteanonym
最新回复
(
0
)