2020_2021学年高中英语Module4WhichEnglishFunctionandGrammar课时作业含解析外研版选修8

Module 4 Which EnglishINCLUDEPICTURE"能力提升教师.tif"Ⅰ.阅读理解Even if trees cannot walk, they are still on t

Module4WhichEnglish Ⅰ.阅读理解 Eveniftreescannotwalk,theyarestillonthemove. InpartsoftheArctic,entireforestsaremovingnorthward.Acrossthe Arctic,temperaturesarerisingfasterthananywhereelseintheworld.Asthat happens,thetreelinethatmarkswhereforestsstopandthetreelesstundra(冻 土地带)startshasbeenshiftingnorthward.Treesgrowingalongthetreeline mustprotectthemselvesfromthecoldwind.Todothis,_plantstendtogrow horizontal(水平的)brancheslowtotheground.Theenergyittakesfortreesto growthiswaymeanstheydon'thaveenoughenergytomakeseeds. ButasEarth'sclimatehasbeenwarming,treesnolongerhavetojustgrow horizontally.Manycaninsteadgrowup,towardthesky.Thistakesless energy.Andwithallthatleftoverenergy,thesetreeshavestartedproducing moreseeds.Thishappensespeciallyinplaceswherethewhitespruce(白云杉) grows. Whitespruce,whichisaNorthAmericantree,isquiteabletoproducea lotofseeds,whichcanmovelongdistancesinthewind.Whenwind－blownseeds enduponthetundrabeyondthetreeline,theyeventuallycansprout(发芽)new trees.Thisexplainshowaforestcanmove.Ofcourse,theprocesswouldwork onlyifthetundrawerewarmenough.Butinrecentyears,thewholeplanethas beenwarming. Newtreeswillprovidesheltersforsomesnow,keepingthesun'sraysfrom makingthewhitesurfacedisappear.Instead,thetreesabsorbthesun's heat.Thiswarmsthesurroundingair.Theextrawarmthencouragesevenmoretrees toproduceseeds.Thatfurtherboostsaforest'sabilitytoexpand.Inaddition, moretreeswilltrapmoresnow,preventingmuchofitfrombeingblown away.Snowcantrapheatinthesoilbelow,whichencouragestreestogrow.The recentriseoftemperaturehashelpedmoretreesgrowpastthetreeline.People worryaboutimpactsontheanimalsthatdependonfrozenconditionsforfood andshelter. 本文是一篇报道，主要报道了由于气温升高，北极部分地区的森林正在向北移动的事件