首页
登录
职称英语
Marine ecosystems certainly have less permanence than terrestrial ecosystems
Marine ecosystems certainly have less permanence than terrestrial ecosystems
游客
2024-01-10
54
管理
问题
Marine ecosystems certainly have less permanence than terrestrial ecosystems. Ashore, ecologists are not confronted with shifting ecological discontinuities, or with changes in the characteristic conditions of individual ecosystems, because, unless man intervenes, the tree line on a mountain or the passage between grassland and savannah remains approximately static over a human lifetime. It is only on the millennial scale that such boundaries migrate significantly, or that characteristic regional ecosystems disappear. Urban sprawl, deforestation, overgrazing, and intensive agriculture are accomplishing in a few decades what nature cannily do in centuries, but that sad fact does not alter the argument. Although the human population explosion can produce pressures that rapidly shift ecological boundaries and modify ecosystems ashore, it is paradoxically more difficult directly to modify the average locations of the ephemeral and shifting
ecological boundaries of the sea
. We can accomplish this only indirectly by atmospheric modification, resulting in a changed global climate and a shifted ocean circulation. [br] The passage indicates which of the following about the “ecological boundaries of the sea?”
选项
A、They have become increasingly sensitive to changes in global climate.
B、They are not significantly impacted by changes in Earth’s atmosphere.
C、Their stability is essential to the health of marine ecosystems.
D、They are more closely tied to surrounding physical conditions than are analogous boundaries on land.
E、They are less susceptible to direct human intervention than are analogous boundaries on land.
答案
E
解析
根据五六两句,人类可以直接改变陆地生态界限,但是要想改变海洋生态界限,只能通过改变大气来间接产生影响。A项海洋生态界限确实受到大气影响,但是看不出increasingly。B项表述相反。C项文中未提及。D项文中未提及。
转载请注明原文地址:https://tihaiku.com/zcyy/3349542.html
相关试题推荐
Justastheauthors’bookoneelsisoftenakeytextforcoursesinmarinevert
CertainlyMurray’spreoccupationwiththetaskofeditingtheOxfordEnglishDic
Marineecosystemscertainlyhavelesspermanencethanterrestrialecosystems
Ourterrestrialfoodsupplycomesfromecosystemstransformedtoproduceaf
Whatisthewriter’sconclusionconcerningthedeclineofmarineresources?A、The
Timekeeper:InventionofMarine
Timekeeper:InventionofMarine
Timekeeper:InventionofMarine
Timekeeper:InventionofMarine
Timekeeper:InventionofMarine
随机试题
CulturalShock"Cultureshock"mightbecalledanoccup
EversinceAesop,fantasyhasplayedanimportantroleinchildren’sliterat
EffectiveAssignmentsUsingLibraryandInternetResourcesFacul
如,已知AE=3AB,BF=2BC。若ΔABC的面积是2,则ΔAEF的面积为A.
21A的特征值为2,-2,1,B的所有特征值为3,7,1,所以|B|=3×7×1=21。
下列说法正确的是()。A.返工品是技术上可以修复的有质量问题的产品 B.废品是
2007年8月19日20时10分左右,位于山东省滨州市邹平县境内的山东魏桥创业集
(2019年真题)工业企业的下列现金收支中,属于筹资活动产生的现金流量的有( )
下列验收层次中,验收合格规定包括观感质量验收项目的有( )。A.检验批 B.
慢性肾功能不全出现肾性贫血最合适的治疗药物是( )。A.口服碳酸钙 B.必需
最新回复
(
0
)