首页
登录
职称英语
[originaltext] Your professor has asked me to talk to you today about the to
[originaltext] Your professor has asked me to talk to you today about the to
游客
2024-06-16
67
管理
问题
Your professor has asked me to talk to you today about the topic that should be of real concern to civil engineers: the erosion of the US beaches. Let me start with some statistics, Did you know that 90% of the coast in this country is eroding, on the gulf of Mexico for instance, erosion averages 4 to 5 feet per year? Over the past 20 years, there has been an increase in building along the coast, even though geologists and environmentalists have been warning communities about problems like erosion. Someway, communities have tried to protect their buildings and roads and to build seawalls. However, geologists have found that such stabilizing structures actually speed up the destruction of the beaches. These beaches with seawalls, called stabilized beaches, are much narrower than beaches without them. You may wonder how seawalls speed up beach loss. The explanation is simple. If the flow of the beaches is gentle, the water energy is lessened as it washes up along the shore. It is reduced even more that returns to the sea so it doesn’t carry back much sand. On the other hand, when the water hits the nearly vertical face of the seawall, it goes straight back to the sea with the full force of its energy and it carries back a great deal of sand. Because of the real risk of losing beaches, many geologists support a ban on all types of stabilizing construction on shorelines.
选项
A、By sending water directly back to the sea with great force.
B、By reducing wave energy.
C、By reducing beach width.
D、By stabilizing beachfront construction.
答案
B
解析
How does a gently sloping beach help prevent erosion?
转载请注明原文地址:http://tihaiku.com/zcyy/3636996.html
相关试题推荐
[originaltext]M:Doyoufeellikegoingtothecinema? W:Oh,yes.Whatkindof
[originaltext]M:Doyoufeellikegoingtothecinema? W:Oh,yes.Whatkindof
[originaltext]W:Goodmorning,sir.CanIhelpyou?M:I’mlookingfor5or6cus
[originaltext]M:Iheardyouhadacceptedanofferfromabigcorporation.W:Yes
[originaltext]W:IsMaryreadytogototheairport?M:Ready?Shehasn’tevenfi
[originaltext]M:Ilikethegreencoat,butitcoststwiceasmuchasthatblueo
[originaltext]W:I’mlosingmysleep.Ifeeltiredandsleepyallthetime.I’ve
[originaltext]M:I’veheardthatyouplaytheviolinverywell.W:Thankyou.Il
[originaltext]M:I’veheardthatyouplaytheviolinverywell.W:Thankyou.Il
[originaltext]W:Nicetoseeyouagain,John.Ihopeyou’refeelingbetter.M:I’
随机试题
Electroniccommunication,duetoitsspeedandbroadcastingability,isfund
September7th,2004A
若f(x)=xsin|x|,则( )。A.f″(0)不存在 B.f″(0)=
以下说法错误的是()。A.所有结构构件均应进行承载力计算 B.地震等偶然荷载
在有关流水施工的概念中,下列正确的是( )。A、对于非节奏专业流水施工,工作队
联合国第37届会议批准的“老龄问题国际行动计划”是在A.1992年B.1952年
从服从正态分布的无限总体中分别抽取容量为13,32,45的样本,当样本容量增大时
设函数f(x)在x=a的某个邻域内连续,且f(a)为其极大值,则存在δ>0,当x
集体合同与劳动合同的区别体现在( )。A.功能不同 B.主体不同 C.内容
根据我国现行建设工程投资构成,属于工程费用构成的是()。A.建设用地费 B.预
最新回复
(
0
)