资源描述：
《(新课标)2016届高考英语二轮复习 攻关篇 专题五 生态环保类课件.ppt》由会员上传分享，免费在线阅读，更多相关内容在PPT专区-天天文库。
1、专题五 生态环保类【典例示范】ABA(2015浙江卷,C篇)Ifhumansweretrulyathomeunderthelightofthemoonandstars,wewouldgoindarknesshappily,themidnightworldasvisibletousasitistothevastnumberofnocturnal(夜间活动的)speciesonthisplanet.Instead,wearediurnalcreatures,witheyesadaptedtolivinginthesun’slight
2、.Thisisabasicevolutionaryfact,eventhoughmostofusdon’tthinkofourselvesasdiurnalbeings.Yetit’stheonlywaytoexplainwhatwe’vedonetothenight:We’veengineeredittoreceiveusbyfillingitwithlight.ABThebenefitsofthiskindofengineeringcomewithconsequences—calledlightpollution—whose
3、effectsscientistsareonlynowbeginningtostudy.Lightpollutionislargelytheresultofbadlightingdesign,whichallowsartificiallighttoshineoutwardandupwardintothesky.Ill-designedlightingwashesoutthedarknessofnightandcompletelychangesthelightlevels—andlightrhythms—towhichmanyfo
4、rmsoflife,includingourselves,haveadapted.Whereverhumanlightspillsintothenaturalworld,someaspectoflifeisaffected.Inmostcitiestheskylooksasthoughithasbeenemptiedofstars,leavingbehindavacanthaze(霾)thatmirrorsourfearofthedark.We’vegrownsousedtothisorangehazethattheorigin
5、algloryofanunlitnight—darkenoughfortheplanetVenustothrowshadowsonEarth—iswhollybeyondourexperience,beyondmemoryalmost.ABWe’velitupthenightasifitwereanunoccupiedcountry,whennothingcouldbefurtherfromthetruth.Amongmammalsalone,thenumberofnocturnalspeciesisastonishing.Li
6、ghtisapowerfulbiologicalforce,andonmanyspeciesitactsasamagnet(磁铁).Theeffectissopowerfulthatscientistsspeakofsongbirdsandseabirdsbeing“captured”bysearchlightsonlandorbythelightfromgasflaresonmarineoilplatforms.Migratingatnight,birdstendtocollidewithbrightlylittallbuil
7、dings.Frogslivingnearbrightlylithighwayssuffernocturnallightlevelsthatareasmuchasamilliontimesbrighterthannormal,throwingnearlyeveryaspectoftheirbehavioroutofjoint,includingtheirnighttimebreedingchoruses.Humansarenolesstrappedbylightpollutionthanthefrogs.Likemostothe
8、rcreatures,wedoneeddarkness.Darknessisasessentialtoourbiologicalwelfare,toourinternalclockwork,aslightitself.ABLivinginaglareofouro
