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1、英語專業(yè)八級考試TEM-8閱讀理解練習(xí)冊（1）(英語專業(yè)2012級)UNIT1TextAEveryminuteofeveryday,whatecologist生態(tài)學(xué)家JamesCarltoncallsaglobal“conveyorbelt”,redistributesoceanorganisms生物.It’splanetwidebiologicaldisruption生物的破壞thatscientistshavebarelybeguntounderstand.Dr.Carlton—anoceanograph
2、eratWilliamsCollegein81Williamstown,Mass.—explainsthat,atanygivenmoment,“Thereareseveralthousandmarinespeciestraveling…intheballastwaterofships.”Thesecreaturesmovefromcoastalwaterswheretheyfitintothelocalweboflifetoplaceswheresomeofthemcouldtearthatwebapart
3、.Thisisthelargerdimensionoftheinfamous無恥的，邪惡的invasionoffish-destroying,pipe-cloggingzebramussels有斑馬紋的貽貝.Suchvoracious貪婪的invadersatleastmaketheirpresenceknown.WhatconcernsCarltonandhisfellowmarineecologistsisthelackofknowledgeaboutthehundredsofalieninvaderst
4、hatquietlyentercoastalwatersaroundtheworldeveryday.Manyofthemprobablyjustdieout.Somebenignly親切地，仁慈地—orevenbeneficially—jointhelocalscene.Butsomewillmaketrouble.Inonesense,thisisanoldstory.Organismshaveriddenshipsforcenturies.Theyhaveclungtohullsandcomealong
5、withcargo.What’snewisthescaleandspeedofthemigrationsmadepossiblebythemassivevolumeofship-ballastwater壓載水—takenintoprovideshipstability—continuouslymovingaroundtheworld…Shipsloadupwithballastwateranditsinhabitantsincoastalwatersofoneportanddumptheballastinan
6、otherportthatmaybethousandsofkilometersaway.Asingleloadcanruntohundredsofgallons.Somelargershipstakeonasmuchas40milliongallons.Thecreaturesthatcomealongtendtobeintheirlarvafree-floatingstage.Whendischarged81排出inalienwaterstheycanmatureintocrabs,jellyfish水母,
7、slugs鼻涕蟲，蛞蝓,andmanyotherforms.Sincetheprobleminvolvescoastalspecies,simplybanningballastdumpsincoastalwaterswould,intheory,solveit.Coastalorganismsinballastwaterthatisflushedintomidoceanwouldnotsurvive.SuchabanhasworkedforNorthAmericanInlandWaterway.Butitwo
8、uldbehardtoenforceitworldwide.Heatingballastwaterorstrainingitshouldalsohaltthespeciesspread.Butbeforeanysuchworldwideregulationswereimposed,scientistswouldneedaclearerviewofwhatisgoingon.Thecontinuous
