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Thiswebsitewouldliketoremindyou:Yourbrowser(Safari7)isoutofdate.Updateyourbrowserfor moresecurity,comfortandthebestexperienceonthissite. EncyclopedicEntry taiga borealforest Forthecompleteencyclopedicentrywithmediaresources,visit: http://nationalgeographic.org/encyclopedia/taiga/ Thetaigaisaforestofthecold,subarcticregion.Thesubarcticisanareaofthe NorthernHemispherethatliesjustsouthoftheArcticCircle.Thetaigaliesbetween thetundratothenorthandtemperateforeststothesouth. Alaska,Canada,Scandinavia,andSiberiahavetaigas.InRussia,theworld’slargest taigastretchesabout5,800kilometers(3,600miles),fromthePacificOceantothe UralMountains.Thistaigaregionwascompletelyglaciated,orcoveredbyglaciers, duringthelasticeage. Thesoilbeneaththetaigaoftencontainspermafrost—alayerofpermanently frozensoil.Inotherareas,alayerofbedrockliesjustbeneaththesoil.Both permafrostandrockpreventwaterfromdrainingfromthetoplayersofsoil.This createsshallowbogsknownasmuskegs.Muskegscanlooklikesolidground, becausetheyarecoveredwithmoss,shortgrasses,andsometimeseventrees. However,thegroundisactuallywetandspongy. PlantsandFungi Taigasarethickforests.Coniferoustrees,suchasspruce,pine,andfir,are common.Coniferoustreeshaveneedlesinsteadofbroadleaves,andtheirseeds growinsideprotective,woodycones.Whiledeciduoustreesoftemperateforests losetheirleavesinwinter,conifersneverlosetheirneedles.Forthisreason, conifersarealsocalled“evergreens.” Conifershaveadaptedtosurvivethelong,coldwintersandshortsummersofthe 1of7 × taiga.Theirneedlescontainverylittlesap,whichhelpspreventfreezing.Theirdark colorandtriangle-shapedsideshelpthemcatchandabsorbasmuchofthesun’s lightaspossible.Inthetaiga,treegrowthisthickestbesidemuskegsandlakes formedbyglaciers. Taigashavefewnativeplantsbesidesconifers.Thesoilofthetaigahasfew nutrients.Itcanalsofreeze,makingitdifficultformanyplantstotakeroot.The larchisoneoftheonlydeciduoustreesabletosurviveinthefreezingnorthern taiga. Insteadofshrubsandflowers,mosses,lichens,andmushroomscoverthefloor ofataiga.Theseorganismscangrowdirectlyontheground,orhaveveryshallow roots.Theycansurviveinthecold,andwithlittlewaterorsunlight. AnimalsoftheTaiga Manykindsofanimalsliveinthetaiga.Allanimalshavetobewell-adaptedtothe cold.Birdsnativetothetaigausuallymigratesouthduringthefreezingwinter months.Smallanimals,mostlyrodents,liveclosetothefloor.Manybirdsofprey, suchasowlsandeagles,hunttheseanimalsfromthetreesofthetaiga. Moose,thelargesttypeofdeerintheworld,isabletoliveinthecoldtaiga.Likeall deer,mooseareherbivores.Theyfavortheaquaticplantsgrowingonthetaiga’s bogsandstreams. Fewlargecarnivorousanimalsliveinthetaiga.Bearsandlynxarefairlycommon. Thelargestcatintheworld,the300-kilogram(660-pound)Siberiantiger,isa nativetaigaspecies.SiberiantigersliveinasmallpartofeasternSiberia.Theyhunt mooseandwildboars. ThreatstoTaigas Taigaecosystemsarethreatenedbydirecthumanactivityandclimatechange. Animalsofthetaiga,suchasfoxesorbears,havealwaysbeenhunted.Their warmfurandtoughskin,turnedintoleather,havehelpedpeoplesurviveinharsh climatesforthousandsofyears. 2of7 Themostseriousthreattotaigasdoesnotcomefromhuntingactivity,however. Civilizationisdependentonsturdybuildingsforhomes,industry,andschools.The treesofthetaigaarecutdownforlumberprojects,aswellaspaper,cardboard, andothersupplies.Theexportofwoodandpaperproductsisoneofthemost economicallyimportantindustriesinCanada,forinstance. Clearcuttingisthemostpopulartypeofloggingintaigas.Clearcuttinginvolves cuttingdownallthetreesinadesignatedarea.Thisdestroyshabitatsformany organismsthatliveinandaroundthetrees,andmakesitdifficultfornewtreesto grow.Clearcuttingalsoincreasestheriskoferosionandfloodinginthetaiga. Withoutarootsystemtoanchorit,ataiga’ssoilcanbeblownawaybywindor wornawaybyrainorsnow.Thisexposesthebedrockandpermafrostbeneath thetaiga,whichdoesnotsupportmanyformsoflife. Climatechangeputstaigasindangerindifferentways.Warmingclimate contributestoapartialthawingofthepermafrost.Sincethiswaterhasnoplaceto drain,moreareaofthetaigaistakenoverbymuskegs.Fewtreestakeroot. Warmingtemperaturealsochangesanimalhabitats.Itpushesnativespeciesout andattractsnon-nativespecies.AnimalssuchastheSiberiantigerarenot adaptedtowarmweather.Itscoatistooheavy,anditstorestoomuchbodyfat tothriveinatemperatehabitat.Non-nativeinsectssuchasthebarkbeetlecan infesttreessuchasspruce.Millionsoftheseinsectsboreintothebarkoftrees, layingeggs.Theinfestedtreesdie.Barkbeetleinfestationscankillentireforests andthousandsofhectaresoftaiga. Vocabulary absorb acre Partof Definition Speech verb tosoakup. noun unitofmeasureequalto.4hectares. adapt anchor verb verb Term toadjusttonewsurroundingsoranewsituation. toholdfirmlyinplace. 3of7 Term Partof Definition Speech organismsthathaveawell-definedshapeandlimitedgrowth, canmovevoluntarily,acquirefoodanddigestitinternally, andcanrespondrapidlytostimuli. animal noun aquatic Arctic adjectivehavingtodowithwater. paralelloflatitudethatruns66.5degreesnorthofthe noun Equator. noun typicallyhard,outercoveringofatree. Circle bark barkbeetle noun insectthatnestsinhardwoodtrees. bear noun mammalwithaverylargebody,relativelyshortlimbs,andan elongatedsnout. bedrock bird noun noun solidrockbeneaththeEarth'ssoilandsand. egg-layinganimalwithfeathers,wings,andabeak. boar noun bog noun mammal,relatedtoapig,nativetoEuropeandAsia. wetlandofsoftgroundmademostlyofdecayingplant bore verb boreal forest noun broad adjectivewideorexpansive. matter. todrillortunnelintosomething. landcoveredbyevergreentreesincool,northernlatitudes. Alsocalledtaiga. cardboard noun thick,stiffpapermadeofwoodpulp. carnivorous adjectivemeat-eating. civilization noun complexwayoflifethatdevelopedashumansbeganto developurbansettlements. clearcuttingnoun processofcuttingdownallthevegetationinanarea,usually aspartofaneconomicindustry. climate noun allweatherconditionsforagivenlocationoveraperiodof time. climate change noun gradualchangesinalltheinterconnectedweatherelements onourplanet. conifer noun plantthatproducesseedsinhardcones,suchaspine.Also calledaconiferoustree. deciduous adjectivetypeofplantthatshedsitsleavesonceayear. deer designate noun verb mammalwhosemalemembershaveantlers. tonameorsingleout. 4of7 Term eagle Partof Definition Speech noun ecosystem noun large,powerfulbirdofprey. communityandinteractionsoflivingandnonlivingthingsin anarea. erosion noun evergreen noun actinwhichearthiswornaway,oftenbywater,wind,orice. treethatdoesnotloseitsleaves. export noun goodorservicetradedtoanotherarea. expose verb fat noun touncover. materialfoundinorganismsthatiscolorlessandodorless fir noun andmaybesolidorliquidatroomtemperature. varietyofpinetree. flood flower noun noun overflowofabodyofwaterontoland. blossomorreproductiveorgansofaplant. forest noun fox noun ecosystemfilledwithtreesandunderbrush. typeofmammalrelatedtoadogwithathinmuzzleandthick fringe verb tail. toexistontheborderoredge. fur noun thickhaircoveringtheskinofananimal. glacial retreat noun processbywhichglaciersmeltfasterthanprecipitationcan replacetheice. glacier grass noun noun massoficethatmovesslowlyoverland. typeofplantwithnarrowleaves. herbivore noun home noun organismthateatsmainlyplants. anorganism'snativeplace;couldbearesidence,atownora hunt verb country. topursueandkillananimal,usuallyforfood. noun longperiodofcoldclimatewhereglacierscoverlargeparts oftheEarth.Thelasticeagepeakedabout20,000years industry noun ago.Alsocalledglacialage. activitythatproducesgoodsandservices. infest verb toinvade,overrun,andtakeover. insect noun typeofanimalthatbreathesairandhasabodydividedinto threesegments,withsixlegsandusuallywings. larch leaf noun noun deciduous,coniferoustree. organgrowingfromthestemofaplant. iceage 5of7 Term leather Partof Speech noun Definition skinofananimal,preparedforuseasclothing,protection, shelter,orotheruse. organismcomposedofafungusorfungiandanalgaor lichen noun logging noun lumber noun woodtosawmills. preciselycutpiecesofwoodsuchasboardsorplanks. lynx migrate noun verb largecatnativetoNorhAmerica. tomovefromoneplaceoractivitytoanother. moss noun tinyplantusuallyfoundinmoist,shadyareas. fungus,usuallywithanumbrella-shapedcapontopofa mushroom noun muskeg native species needle noun noun noun non-native noun species Northern noun Hemisphere nutrient noun owl partial cyanobacterium. industryengagedincuttingdowntreesandmovingthe slenderstalk. bog,especiallyoneinNorthAmerica. speciesthatoccurnaturallyinanareaorhabitat.Alsocalled indigenousspecies. long,thin,pointedleaf. atypeofplantoranimalthatisnotindigenoustoaparticular area.Non-nativespeciescansometimescauseeconomicor environmentalharmasaninvasivespecies. halfoftheEarthbetweentheNorthPoleandtheEquator. substanceanorganismneedsforenergy,growth,andlife. noun birdofprey. adjectiveincomplete. permafrost noun permanentlyfrozenlayeroftheEarth'ssurface. pine noun typeofevergreentreewithneedle-shapedleaves. plant noun prey rock noun noun rodent noun root noun organismthatproducesitsownfoodthrough photosynthesisandwhosecellshavewalls. animalthatishuntedandeatenbyotheranimals. naturalsubstancecomposedofsolidmineralmatter. orderofmammalsoftencharacterizedbylongteethfor gnawingandnibbling. partofaplantthatsecuresitinthesoil,obtainswaterand nutrients,andoftenstoresfoodmadebyleaves. 6of7 Term Partof Speech rootsystemnoun sap noun Scandinavianoun Definition allofaplant'sroots. fluidthatdistributesnutrientsthroughoutaplant. regionandnameforsomecountriesinNorthernEurope: Iceland,Norway,Sweden,Finland,andDenmark. seed noun partofaplantfromwhichanewplantgrows. typeofplant,smallerthanatreebuthavingwoody branches. regionoflandstretchingacrossRussiafromtheUral shrub noun Siberia noun Siberian tiger noun endangeredspeciesnativetofareasternSiberia. soil spruce stream subarctic noun noun noun noun toplayeroftheEarth'ssurfacewhereplantscangrow. coniferous,orcone-bearing,tree. bodyofflowingwater. regionjustsouthoftheArcticCircle. survive verb thaw thrive tree tundra verb verb noun noun MountainstothePacificOcean. tolive. evergreenforestincool,northernlatitudes.Alsocalledboreal taiga noun forest. temperate adjectivemoderate. tomelt,orturnfromicetoliquid. todevelopandbesuccessful. typeoflargeplantwithathicktrunkandbranches. cold,treelessregioninArcticandAntarcticclimates. Articles&Profiles WorldWildlifeFund:EastSiberianTaiga Websites NASA:BOREAS—TheBorealEcosystemAtmosphereStudy ©1996–2016NationalGeographicSociety.Allrightsreserved. 7of7