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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
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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.
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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.
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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.
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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
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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.
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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.
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