内容biodiversity嗨考雅思

Itseemsbiodiversityhas eabuzzwordbelovedofpoliticians,conservationists,ersandscientistsalike.Butwhatexactlyisit?TheConventiononBiologicalDiversity,aninternationalagreementtoconserveandsharethenet’sbiologicalriches,providesagoodworkingdefinition:biodiversitycompriseseveryformoflife,fromthesmallestmicrobetothelargestanimalornt,thegenesthatgivethemtheirspecificcharacteristicsandtheofwhichtheyareaInOctober,theWorldConservationUnion(alsoknownasthe )publisheditsupdatedRedListofThreatenedSpeciesarollcallof11,167creaturesfacingextinction-121morethanwhenthelistwaslastpublishedin2000.Butthenewfiguresalmostcertainlyunderestimatethecrisis.Some1.2millionspeciesofanimaland270,000speciesofnthavebeenclassified,butthewell-beingofonlyafractionhasbeenassessed.Theresourcesaresimplynotavailable.Thereportsthat5714ntsarethreatened,forexample,butadmitsthatonly4percentofknownntshavebeenassessed.And,ofcourse,therearethousandsofspeciesthatwehavetodiscover.ManyofthesecouldalsobefacingItisimportanttodevelopapictureofthediversityoflifeonEarthnow,sothatcomparisonscanbemadeinthefutureandtrendsidentified.Butitisn’tnecessarytoobserveeverysingletypeoforganisminanareatogetasnapshotofthehealthoftheecosystem.Inmanyhabitatstherearespeciesthatareparticularlysusceptibletoshiftingconditions,andthesecanbeusedasindicatorInthemedia,itisusuallylarge,charismaticsuchaspandas,elephants,tigersandwhalesthatgetalltheattentionwhenlossofbiodiversityisdiscussed.However,animalsorntsfarlowerdownthefoodchainareoftentheonesvitalforpreservinghabitats-intheprocesssavingtheskinsofthosemoreglamorousspecies.Theseareknownaskeystonespecies.Bystudyingthecomplexfeedingrelationshipswithinhabitats,speciescanbeidentifiedthathaveaparticularlyimportantimpactontheenvironment.Forexample,themembersofthefigfamilyarethestaplefoodforhundredsofdifferentspeciesinmanydifferentcountries,soimportantthatscientistssometimescallfigs“jungleburgers”.Awholerangeofanimals,fromtinyinsectstobirdsandlargemls,feedoneverythingfromthetree’sbarkandleavestoitsflowersandfruits.Manyfigspecieshaveveryspecificpollinators.ThereareseveraldozenspeciesoffigtreeinCostaRica,andadifferenttypeofwasphasevolvedtopollinateeachone.ChrisLyleoftheNaturalHistoryMuseuminLondon-whoisalsoinvolvedintheGlobalTaxonomyInitiativeoftheConventiononBiologicalDiversity-pointsoutthatiffigtreesareaffectedbyglobalwarming,pollution,diseaseoranyothercatastrophe,thelossofbiodiversitywillbeenormous.Similarly,seaottersyamajorroleinthesurvivalofgiantkelpsalongthecoastsofCaliforniaandAlaska.These“marinerains”provideahomeforawiderangeofotherspecies.Thekelpitselfisthemainfoodofpurpleandredseaurchinsandinturntheurchinsareeatenbypredators,particularlyseaotters.Theydetachanurchinfromtheseabedthenfloattothesurfaceandlieontheirbackswiththeurchinsontheirtummy,smashingitopenwithastonebeforeeatingthecontents.Urchinsthatarenoteatentendtospendtheirtimeinrockcrevicestoavoidthepredators.Thisallowsthekelptogrow-anditcangrowmanycentimetersinaday.Astheform,bitsofkelpbreakoffandfalltothebottomtoprovidefoodfortheurchinsintheircrevices.Theseaottersthrivehuntingforseaurchinsinthekelp,andmanyotherfishandinvertebratesliveamongthefronds.Theproblemsstartwhentheseaotterpopulationdeclines.Aslargepredatorstheyarevulnerable-theirnumbersarerelativelysmallsodiseaseorhumanhunterscanwipethemout.Theresultisthattheseaurchinpopulationgrowsuncheckedandtheyroamtheseaflooreatingyoungkelpfronds.Thistendstokeepthekelpveryshortandsdevelo,whichhasahugeimpactonConversely,keystonespeciescanalsomakedangerousalienspecies:theycanwreakwho（毛虫）isavoracious（贪婪的）eaterofpricklypear（刺梨）wasintroducedtoAustraliatocontroltherampantcacti.ItwassosuccessfulthatsomeonethoughtitwouldbeagoodideatointroduceittoCaribbeanislandsthathadthesameproblem.Itsolvedthecactusmenace,butunfortunaysomeofthemothshavenowreachedtheUS -borneonwindsandintourists’luggage-wheretheyaredevastatingthenativecactuspopulationsofFlorida.OrganizationsliketheConventiononBiologicalDiversityworkwithgroupssuchastheUNandwithernmentsandscientiststoraiseawarenessandfundresearch.Anumberofmajorinternationalmeetings-includingtheWorldSummitonSustainableDevelopmentinJohannesburgthisyear-havesettargetsforernmentsaroundtheworldtoslowthelossofbiodiversity.AndtheCITESmeetinginSantiagolastmonthaddedseveralmorenamestoitslistofendangeredspeciesforwhichtradeiscontrolled.Ofcourse,theseagreementswillroveoflimitedvalueifsomecountriesrefusetoimplementthem.Thereiscauseforoptimism,however.Thereseemstobeagrowingunderstandingoftheneedforsustainableagricultureandsustainabletourismtoconservebiodiversity.Problemssuchasillegalloggingarebeingtackledthroughsustainableryprogrammes,withtheemphasisonminimizingtheuseofrainhardwoodsinthedevelopedworldandonrigorousrentingofwhatevertreesareharvested.CITESisyingitspartbycontrollingtradeinwoodfromendangeredtreespecies.Inthesameway,sustainablefarmingtechniquesthatminimizeenvironmentaldamageandavoidmonoculture.Actionatanationalleveloftenmeansinvestinginpubliceducationandawareness.Gettingpeoplelikeyouandmeinvolvedcanbeveryeffective.AustraliaandmanyEuropeancountriesareingincreasinglyefficientatrecyclingmuchoftheirdomesticwaste,forexample,preservingnaturalresourcesandreducingtheuseoffossilfuels.Thisinturnhasadirecteffectonbiodiversitybyminimisingpollution,andanindirecteffectbyreducingtheamountofgreenhousegasesemittedfromincineratorsandlandfillsites.Preservingecosystemsintactforfuturegenerationstoenjoyisobviouslyimportant,butbiodiversityisnotsomekindofoptionalVarietymaybe“thespiceoflife”,butbiologicalvarietyisalsoourlife-supportsystem.Questions14-20DothefollowingstatementsagreewithinformationgiveninReadingPassage2Inboxes14-20onyouranswersheet,write ifthestatementis ifthestatementisNOT ifthestatementisnotgivenintheTheterm“biodiversity”consistsoflivingcreaturesandenvironmentthattheyliveTherearespeciesthathavenotbeenresearchedbecauseit’sunnecessarytostudyallItisnotnecessarytoinvestigateallcreaturesinacertainThepressmoreoftenthannotfocusesonanimalswell-ThereisasuccessfulcasethatcactusmothysapositiveroleintheUsageofhardwoodsisforbiddeninsomeEuropeanAgricultureexpertsadvisefarmerstontsinglecropsinthefieldintermsofsustainableQuestions21-26CompletethefollowingsummaryoftheparagraphsofReadingPassage,usingnomorethantwowordsfromtheReadingPassageforeachanswer.Writeyouranswersinboxes21-26onyouranswersheet.Becauseoftheignorancebroughtbymedia,peopletendtoneglectsignificantcreaturesEverycreaturehasdietconnectionswithothers,suchas 22,whichprovideamajorityoffoodforotherspecies.InsomestatesofAmerica,declineinnumberofseaottersleadstotheboom 23.Animpressingcaseisthat successfullytacklesthentcactiin25.however,theoperationisneededfortheernmenttoincreasetheirfinancialsupportin26 【原文参考依据-A末句】thegenesthatgivethemtheirspecificcharacteristicsandtheecosystemsofwhichtheyareapart.定于；生物多样性包含所有的生命形式，从最小的微生物第4行到结束【原文参考依据-B....butthewell-beingofonlyafractionhasbeenassessed.但是科学家目前只对很小的一部分的生存现状作出了评估，相关的数据无法获得。FALSEB段中部倒数第5行notavaible的原因，不是没必要因为Informationnotavailablenotunnecessary【原文参考依据-CButitisn’tnecessarytoobverveeverysingletypeoforganisminanareatogetasnapshotofthehealthoftheecosystem.但是有没有必要将一个地区的每一个生物的类型进行调研，来了解它所处的生态环境的健康。TRUEC段第2行3行TRUE【原文参考依据-D】Inthemedia,itisusuallylarge,charismaticanimalssuchaspandaselephantstigersandwhalesthatgetalltheattentionwhenlossofbiodiversityisdiscussed.样性受到影响是会引起大家广泛的关注。D段第一行FALSE【原文参考依据-G】Itsolvedthecactusmenace,butunfort