首页
登录
职称英语
What happens to trees each year? [br] [originaltext] During this century, a
What happens to trees each year? [br] [originaltext] During this century, a
游客
2023-11-23
72
管理
问题
What happens to trees each year? [br]
During this century, archaeologists have discovered that trees can be a valuable tool for measuring time. In scientific terms, this method is called dendrochronology. Dendrochronology is based on the scientific discovery that each year a tree grows a new layer of wood. When you cut down a tree, for example, you can see and count the layers of concentric circles. These circles will reveal a great deal of information. The layers vary in color and in thickness. These variations are a result of differing climate conditions from year to year that affect the growth of the annual tings. Cold weather, for example, creates thinner and lighter tings while hot weather produces thicker and darker rings. All trees that grow in the same region will have roughly the same pattern of annual rings, and this can be used as a source of comparison and measurement.
Early in this century, archaeologists began using the rings to date ruined structures and figures built in the southwestern United States. They did this by comparing the rings of the wood found in the ruins with the rings of recently cut trees. Slowly but surely, the system was extended backwards in time to measure older ruins. The heavy forestry of the United States, coupled with the relative youth of its history, led to a fairly uncomplicated study. Eventually, dendrochronology produced an accurate time and weather record for the American southwest that extended over 2000 years.
选项
A、The climate.
B、The exposure to light.
C、The length of time.
D、The fertility of the soil.
答案
A
解析
原文中有“These variations are a result of differing climate conditions from year to year that affect the growth of the annual rings.”一句。
转载请注明原文地址:http://tihaiku.com/zcyy/3212487.html
相关试题推荐
Youngpeoplearefacinganuncertainfuture.Asthe21stcenturydawned,the
Youngpeoplearefacinganuncertainfuture.Asthe21stcenturydawned,the
Youngpeoplearefacinganuncertainfuture.Asthe21stcenturydawned,the
Youngpeoplearefacinganuncertainfuture.Asthe21stcenturydawned,the
Youngpeoplearefacinganuncertainfuture.Asthe21stcenturydawned,the
Attheturnofthe20thcentury,DutchphysicianChristiaanEijkmanshowed
Attheturnofthe20thcentury,DutchphysicianChristiaanEijkmanshowed
Attheturnofthe20thcentury,DutchphysicianChristiaanEijkmanshowed
Attheturnofthe20thcentury,DutchphysicianChristiaanEijkmanshowed
Attheturnofthe20thcentury,DutchphysicianChristiaanEijkmanshowed
随机试题
A.abuseB.appreciatedC.attractedD.linkedE.mixtureF.unionG.pe
[originaltext]M:Oh,Ijustgotsomebadnewstoday.W:Whathappened,Tony?M:
Completethenotesbelow.WriteNOMORETHANTWOWORDSforeachanswer.
使用牙挺时一般是将支点放在A.远申牙槽嵴 B.近中牙槽嵴 C.舌侧骨板 D
全陪要做好的物质准备有()A.身份证 B.大量现金 C.接团资料 D.游客
运维班值班方式应满足日常运维和应急工作的需要,运维班驻地应()小时有人值班,并保
各级别轿车历年销售份额(%) 2001~2010年各级别轿车历年销售份额
国际债券中一般到期一次还本、每年付息一次的长期固定利率债券被称为()。A:外国债
关于连续生产设备安装的测量,下列说法不正确的是( )。A.中心标板应在浇灌基础
下列有关胆道系统的描述正确的是 A.左、右肝管汇合形成胆总管 B.肝总管最长
最新回复
(
0
)