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An ecosystem is a geographic area where plants, animals, and other organisms, as well as weather and landscape, work together to form a bubble ... Skiptocontent Donate Account Menu Close Account ThisliststhelogosofprogramsorpartnersofNGEducationwhichhaveprovidedorcontributedthecontentonthispage. Poweredby Twitter Facebook Pinterest GoogleClassroom Email Print EncyclopedicEntry Vocabulary Anecosystemisageographicareawhereplants,animals,andotherorganisms,aswellasweatherandlandscape,worktogethertoformabubbleoflife.Ecosystemscontainbioticorliving,parts,aswellasabioticfactors,ornonlivingparts.Bioticfactorsincludeplants,animals,andotherorganisms.Abioticfactorsincluderocks,temperature,andhumidity.Everyfactorinanecosystemdependsoneveryotherfactor,eitherdirectlyorindirectly.Achangeinthetemperatureofanecosystemwilloftenaffectwhatplantswillgrowthere,forinstance.Animalsthatdependonplantsforfoodandshelterwillhavetoadapttothechanges,movetoanotherecosystem,orperish.Ecosystemscanbeverylargeorverysmall.Tidepools,thepondsleftbytheoceanasthetidegoesout,arecomplete,tinyecosystems.Tidepoolscontainseaweed,akindofalgae,whichusesphotosynthesistocreatefood.Herbivoressuchasabaloneeattheseaweed.Carnivoressuchasseastarseatotheranimalsinthetidepool,suchasclamsormussels.Tidepoolsdependonthechanginglevelofoceanwater.Someorganisms,suchasseaweed,thriveinanaquaticenvironment,whenthetideisinandthepoolisfull.Otherorganisms,suchashermitcrabs,cannotliveunderwateranddependontheshallowpoolsleftbylowtides.Inthisway,thebioticpartsoftheecosystemdependonabioticfactors.ThewholesurfaceofEarthisaseriesofconnectedecosystems.Ecosystemsareoftenconnectedinalargerbiome.Biomesarelargesectionsofland,sea,oratmosphere.Forests,ponds,reefs,andtundraarealltypesofbiomes,forexample.They'reorganizedverygenerally,basedonthetypesofplantsandanimalsthatliveinthem.Withineachforest,eachpond,eachreef,oreachsectionoftundra,you'llfindmanydifferentecosystems.ThebiomeoftheSaharaDesert,forinstance,includesawidevarietyofecosystems.Thearidclimateandhotweathercharacterizethebiome.WithintheSaharaareoasisecosystems,whichhavedatepalmtrees,freshwater,andanimalssuchascrocodiles.TheSaharaalsohasduneecosystems,withthechanginglandscapedeterminedbythewind.Organismsintheseecosystems,suchassnakesorscorpions,mustbeabletosurviveinsanddunesforlongperiodsoftime.TheSaharaevenincludesamarineenvironment,wheretheAtlanticOceancreatescoolfogsontheNorthwestAfricancoast.Shrubsandanimalsthatfeedonsmalltrees,suchasgoats,liveinthisSaharaecosystem.Evensimilar-soundingbiomescouldhavecompletelydifferentecosystems.ThebiomeoftheSaharaDesert,forinstance,isverydifferentfromthebiomeoftheGobiDesertinMongoliaandChina.TheGobiisacolddesert,withfrequentsnowfallandfreezingtemperatures.UnliketheSahara,theGobihasecosystemsbasednotinsand,butkilometersofbarerock.Somegrassesareabletogrowinthecold,dryclimate.Asaresult,theseGobiecosystemshavegrazinganimalssuchasgazellesandeventakhi,anendangeredspeciesofwildhorse.EventhecolddesertecosystemsoftheGobiaredistinctfromthefreezingdesertecosystemsofAntarctica.Antarcticasthickicesheetcoversacontinentmadealmostentirelyofdry,barerock.Onlyafewmossesgrowinthisdesertecosystem,supportingonlyafewbirds,suchasskuas.ThreatstoEcosystemsForthousandsofyears,peoplehaveinteractedwithecosystems.Manyculturesdevelopedaroundnearbyecosystems.ManyNativeAmericantribesofNorthAmericasGreatPlainsdevelopedacomplexlifestylebasedonthenativeplantsandanimalsofplainsecosystems,forinstance.Bison,alargegrazinganimalnativetotheGreatPlains,becamethemostimportantbioticfactorinmanyPlainsIndianscultures,suchastheLakotaorKiowa.Bisonaresometimesmistakenlycalledbuffalo.Thesetribesusedbuffalohidesforshelterandclothing,buffalomeatforfood,andbuffalohornfortools.ThetallgrassprairieoftheGreatPlainssupportedbisonherds,whichtribesfollowedthroughouttheyear. Ashumanpopulationshavegrown,however,peoplehaveovertakenmanyecosystems.ThetallgrassprairieoftheGreatPlains,forinstance,becamefarmland.Astheecosystemshrunk,fewerbisoncouldsurvive.Today,afewherdssurviveinprotectedecosystemssuchasYellowstoneNationalPark.InthetropicalrainforestecosystemssurroundingtheAmazonRiverinSouthAmerica,asimilarsituationistakingplace.TheAmazonrainforestincludeshundredsofecosystems,includingcanopies,understories,andforestfloors.Theseecosystemssupportvastfoodwebs.Canopiesareecosystemsatthetopoftherainforest,wheretall,thintreessuchasfigsgrowinsearchofsunlight.Canopyecosystemsalsoincludeotherplants,calledepiphytes,whichgrowdirectlyonbranches.Understoryecosystemsexistunderthecanopy.Theyaredarkerandmorehumidthancanopies.Animalssuchasmonkeysliveinunderstoryecosystems,eatingfruitsfromtreesaswellassmalleranimalslikebeetles.Forestfloorecosystemssupportawidevarietyofflowers,whicharefedonbyinsectslikebutterflies.Butterflies,inturn,providefoodforanimalssuchasspidersinforestfloorecosystems.HumanactivitythreatensalltheserainforestecosystemsintheAmazon.Thousandsofacresoflandareclearedforfarmland,housing,andindustry.CountriesoftheAmazonrainforest,suchasBrazil,Venezuela,andEcuador,areunderdeveloped.Cuttingdowntreestomakeroomforcropssuchassoyandcornbenefitsmanypoorfarmers.Theseresourcesgivethemareliablesourceofincomeandfood.Childrenmaybeabletoattendschool,andfamiliesareabletoaffordbetterhealthcare.However,thedestructionofrainforestecosystemshasitscosts.Manymodernmedicineshavebeendevelopedfromrainforestplants.Curare,amusclerelaxant,andquinine,usedtotreatmalaria,arejusttwoofthesemedicines.Manyscientistsworrythatdestroyingtherainforestecosystemmaypreventmoremedicinesfrombeingdeveloped.Therainforestecosystemsalsomakepoorfarmland.UnliketherichsoilsoftheGreatPlains,wherepeopledestroyedthetallgrassprairieecosystem,Amazonrainforestsoilisthinandhasfewnutrients.Onlyafewseasonsofcropsmaygrowbeforeallthenutrientsareabsorbed.Thefarmeroragribusinessmustmoveontothenextpatchofland,leavinganemptyecosystembehind.ReboundingEcosystemsEcosystemscanrecoverfromdestruction,however.ThedelicatecoralreefecosystemsintheSouthPacificareatriskduetorisingoceantemperaturesanddecreasedsalinity.Coralsbleach,orlosetheirbrightcolors,inwaterthatistoowarm.Theydieinwaterthatisntsaltyenough.Withoutthereefstructure,theecosystemcollapses.Organismssuchasalgae,plantssuchasseagrass,andanimalssuchasfish,snakes,andshrimpdisappear.Mostcoralreefecosystemswillbouncebackfromcollapse.Asoceantemperaturecoolsandretainsmoresalt,thebrightlycoloredcoralsreturn.Slowly,theybuildreefs.Algae,plants,andanimalsalsoreturn.Individualpeople,cultures,andgovernmentsareworkingtopreserveecosystemsthatareimportanttothem.ThegovernmentofEcuador,forinstance,recognizesecosystemrightsinthecountrysconstitution.Theso-calledRightsofNaturesaysNatureorPachamama[Earth],wherelifeisreproducedandexists,hastherighttoexist,persist,maintainandregenerateitsvitalcycles,structure,functionsanditsprocessesinevolution.Everyperson,people,communityornationality,willbeabletodemandtherecognitionsofrightsfornaturebeforethepublicbodies.Ecuadorishomenotonlytorainforestecosystems,butalsoriverecosystemsandtheremarkableecosystemsontheGalapagosIslands. TallgrassesandBisonbison—mustbethetallgrassprairieecosystem. PhotographbyLelaBouse-McCracken,MyShot EcocideThedestructionofentireecosystemsbyhumanbeingshasbeencalledecocide,ormurderoftheenvironment. HumanEcosystem"Humanecosystem"isthetermscientistsusetostudythewaypeopleinteractwiththeirecosystems.Thestudyofhumanecosystemsconsidersgeography,ecology,technology,economics,politics,andhistory.Thestudyofurbanecosystemsfocusesoncitiesandsuburbs. CoralTriangleThemostdiverseecosystemintheworldisthehugeCoralTriangleinSoutheastAsia.TheCoralTrianglestretchesfromthePhilippinesinthenorthtotheSolomonIslandsintheeasttotheislandsofIndonesiaandPapuainthewest. BactrianandDromedaryDifferentdesertecosystemssupportdifferentspeciesofcamels.Thedromedarycamelistallandfast,withlonglegs.Itisnativetothehot,drydesertsofNorthAfricaandtheArabianPeninsula.TheBactriancamelhasathickercoat,isshorter,andhasmorebodyfatthanthedromedary.TheBactriancamelisnativetothecolddesertsteppesofCentralAsia.Itiseasytotellthetwotypesofcamelsapart:Dromedarieshaveonehump,Bactrianshavetwo. abiotic Adjective lackingorabsentoflife. adapt Verb toadjusttonewsurroundingsoranewsituation. agribusiness Noun thestrategyofapplyingprofit-makingpracticestotheoperationoffarmsandranches. algae PluralNoun (singular:alga)diversegroupofaquaticorganisms,thelargestofwhichareseaweeds. animal Noun organismsthathaveawell-definedshapeandlimitedgrowth,canmovevoluntarily,acquirefoodanddigestitinternally,andcanrespondrapidlytostimuli. aquatic Adjective havingtodowithwater. arid Adjective dry. biome Noun areaoftheplanetwhichcanbeclassifiedaccordingtotheplantandanimallifeinit. bioticfactor Noun effectorimpactofanorganismonitsenvironment. bison Noun largemammalnativetoNorthAmerica.AlsocalledAmericanbuffalo. butterfly Noun typeofflyinginsectwithlarge,colorfulwings. canopy Noun oneofthetoplayersofaforest,formedbythethickleavesofverytalltrees. carnivore Noun organismthateatsmeat. characterize Verb todescribethecharacteristicsofsomething. climate Noun allweatherconditionsforagivenlocationoveraperiodoftime. complex Adjective complicated. constitution Noun systemofideasandgenerallawsthatguideanation,state,orotherorganization. continent Noun oneofthesevenmainlandmassesonEarth. coralreef Noun rockyoceanfeaturesmadeupofmillionsofcoralskeletons. corn noun,adjective tallcerealplantwithlargeseeds(kernels)cultivatedforfoodandindustry.Alsocalledmaize. crocodile Noun reptilenativetopartsofAfrica,Asia,andtheAmericas. crop Noun agriculturalproduce. culture Noun learnedbehaviorofpeople,includingtheirlanguages,beliefsystems,socialstructures,institutions,andmaterialgoods. curare Noun resinobtainedfromSouthAmericantrees,oftendriedandusedasaningredientinmusclerelaxants. datepalm Noun typeoffruittree. delicate Adjective fragileoreasilydamaged. desert Noun areaoflandthatreceivesnomorethan25centimeters(10inches)ofprecipitationayear. destruction Noun ruin. determine Verb todecide. distinct Adjective uniqueoridentifiable. dune Noun amoundorridgeofloosesandthathasbeendepositedbywind. ecocide Noun totaldestructionofanecosystem. ecology Noun branchofbiologythatstudiestherelationshipbetweenlivingorganismsandtheirenvironment. economics Noun studyofmonetarysystems,orthecreation,buying,andsellingofgoodsandservices. ecosystem Noun communityandinteractionsoflivingandnonlivingthingsinanarea. endangeredspecies Noun organismthreatenedwithextinction. epiphyte Noun plantthatgrowsonthebranchesortrunkofanotherplantorobject. evolution Noun changeinheritabletraitsofapopulationovertime. farmland Noun areausedforagriculture. fig Noun fruitandtreenativetoAsia. flower Noun blossomorreproductiveorgansofaplant. fog Noun cloudsatgroundlevel. food Noun material,usuallyofplantoranimalorigin,thatlivingorganismsusetoobtainnutrients. foodweb Noun allrelatedfoodchainsinanecosystem.Alsocalledafoodcycle. forest Noun ecosystemfilledwithtreesandunderbrush. frequent Adjective often. freshwater Noun waterthatisnotsalty. GalapagosIslands Noun archipelagointhePacificOcean,offthecoastofEcuador. gazelle Noun smallantelopenativetoAfricaandAsia. geographic Adjective havingtodowithplacesandtherelationshipsbetweenpeopleandtheirenvironments. geography Noun studyofplacesandtherelationshipsbetweenpeopleandtheirenvironments. goat Noun hoofedmammaldomesticatedforitsmilk,coat,andflesh. government Noun systemororderofanation,state,orotherpoliticalunit. grass Noun typeofplantwithnarrowleaves. grazinganimal Noun animalthatfeedsongrasses,trees,andshrubs. GreatPlains Noun grasslandregionofNorthAmerica,betweentheRockyMountainsandtheMississippiRiver. healthcare Noun systemforaddressingthephysicalhealthofapopulation. herbivore Noun organismthateatsmainlyplantsandotherproducers. herd Noun groupofanimals. hermitcrab Noun typeofmarineanimal(crustacean)thatusesfoundmaterials,suchasothercreatures'shells,asitsshell. hide Noun leatherskinofananimal. history Noun studyofthepast. humanecosystem Noun environmentconstructedoradaptedtobypeopleandculture. humidity Noun amountofwatervaporintheair. icesheet Noun thicklayerofglacialicethatcoversalargeareaofland. income Noun wages,salary,oramountofmoneyearned. industry Noun activitythatproducesgoodsandservices. insect Noun typeofanimalthatbreathesairandhasabodydividedintothreesegments,withsixlegsandusuallywings. Kiowa Noun peopleandculturenativetotheGreatPlainsofNorthAmerica. Lakota Noun peopleandcultureofsevenSiouxtribesnativetotheGreatPlains. landscape Noun thegeographicfeaturesofaregion. maintain Verb tocontinue,keepup,orsupport. malaria Noun infectiousdiseasecausedbyaparasitecarriedbymosquitoes. marine Adjective havingtodowiththeocean. medicine Noun substanceusedfortreatingillnessordisease. monkey Noun mammalconsideredtobehighlyintelligent,withfourlimbsand,usually,atail. moss Noun tinyplantusuallyfoundinmoist,shadyareas. mussel Noun aquaticanimalwithtwoshellsthatcanopenandcloseforfoodordefense. nutrient Noun substanceanorganismneedsforenergy,growth,andlife. oasis Noun areamadefertilebyasourceoffreshwaterinanotherwisearidregion. ocean Noun largebodyofsaltwaterthatcoversmostoftheEarth. organism Noun livingoronce-livingthing. Pachamama Noun goddessoftheEarthrecognizedbymanyculturesoftheAndesMountains. perish Verb todieorbedestroyed. persist Verb toendureorcontinue. photosynthesis Noun processbywhichplantsturnwater,sunlight,andcarbondioxideintowater,oxygen,andsimplesugars. plain Noun flat,smoothareaatalowelevation. plant Noun organismthatproducesitsownfoodthroughphotosynthesisandwhosecellshavewalls. politics Noun artandscienceofpublicpolicy. pond Noun smallbodyofwatersurroundedbyland. preserve Verb tomaintainandkeepsafefromdamage. public Adjective availabletoanentirecommunity,notlimitedtopayingmembers. quinine Noun drugusedtotreatmalaria. rainforest Noun areaoftall,mostlyevergreentreesandahighamountofrainfall. reef Noun aridgeofrocks,coral,orsandrisingfromtheoceanfloorallthewaytoorneartheocean'ssurface. reliable Adjective dependableorconsistent. remarkable Adjective unusualanddramatic. resource Noun availablesupplyofmaterials,goods,orservices.Resourcescanbenaturalorhuman. river Noun largestreamofflowingfreshwater. rock Noun naturalsubstancecomposedofsolidmineralmatter. SaharaDesert Noun world'slargestdesert,innorthAfrica. salinity Noun saltiness. sand Noun small,loosegrainsofdisintegratedrocks. scorpion Noun animalrelatedtoaspiderwithapoisonousstinginitstail. seagrass Noun typeofplantthatgrowsintheocean. seastar Noun marineanimal(echinoderm)withmanyarmsradiatingfromitsbody.Alsocalledastarfish. seaweed Noun marinealgae.Seaweedcanbecomposedofbrown,green,orredalgae,aswellas"blue-greenalgae,"whichisactuallybacteria. shelter Noun structurethatprotectspeopleorotherorganismsfromweatherandotherdangers. shrimp Noun animalthatlivesnearthebottomofoceansandlakes. shrub Noun typeofplant,smallerthanatreebuthavingwoodybranches. skua Noun birdrelatedtotheseagull. snake Noun reptilewithscalesandnolimbs. snowfall Noun amountofsnowataspecificplaceoveraspecificperiodoftime. soil Noun toplayeroftheEarth'ssurfacewhereplantscangrow. soy Noun beans,orfruit,ofthesoybeanplant,nativetoAsia. spider Noun eight-leggedanimal(arachnid)thatusuallyspinswebstocatchfood. survive Verb tolive. takhi Noun endangeredspeciesofwildhorsenativetoCentralAsia.AlsocalledPrzewalski'shorse. tallgrassprairie Noun plainwheregrassesgrowupto2meters(6feet)tall. technology Noun thescienceofusingtoolsandcomplexmachinestomakehumanlifeeasierormoreprofitable. temperature Noun degreeofhotnessorcoldnessmeasuredbyathermometerwithanumericalscale. tide Noun riseandfalloftheocean'swaters,causedbythegravitationalpullofthemoonandsun. tidepool Noun smallpondcreatedbyanebbtideandsubmergedbyahightide. tropical Adjective existinginthetropics,thelatitudesbetweentheTropicofCancerinthenorthandtheTropicofCapricorninthesouth. tundra Noun cold,treelessregioninArcticandAntarcticclimates. underdevelopedcountry Noun countrythathasfallenbehindongoalsofindustrialization,infrastructure,andincome. understory Noun ecosystembetweenthecanopyandfloorofaforest. urbanecosystem Noun environmentofcities,towns,andsuburbs. vast Adjective hugeandspreadout. vital Adjective necessaryorveryimportant. weather Noun stateoftheatmosphere,includingtemperature,atmosphericpressure,wind,humidity,precipitation,andcloudiness. wind Noun movementofair(fromahighpressurezonetoalowpressurezone)causedbytheunevenheatingoftheEarthbythesun. Articles&Profiles NationalGeographicNews:IceShelfCollapsesRevealNewSpecies,EcosystemChanges NationalGeographicMagazine:TallgrassPrairiePreserve Websites NewHampshirePublicTelevision:Natureworks—Ecosystems Credits MediaCredits Theaudio,illustrations,photos,andvideosarecreditedbeneaththemediaasset,exceptforpromotionalimages,whichgenerallylinktoanotherpagethatcontainsthemediacredit.TheRightsHolderformediaisthepersonorgroupcredited. Writers KimRutledge TaraRamroop DianeBoudreau MelissaMcDaniel SantaniTeng ErinSprout HilaryCosta HilaryHall JeffHunt Illustrators MaryCrooks,NationalGeographicSociety TimGunther Editors JeannieEvers,EmdashEditing KaraWest EducatorReviewer NancyWynne Producer Caryl-Sue,NationalGeographicSociety Sources Dunn,MargeryG.(Editor).(1989,1993)."ExploringYourWorld:TheAdventureofGeography."Washington,D.C.:NationalGeographicSociety. 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RelatedResources LimitingFactors   Alimitingfactorisanythingthatconstrainsapopulation'ssizeandslowsorstopsitfromgrowing.Someexamplesoflimitingfactorsarebiotic,likefood,mates,andcompetitionwithotherorganismsforresources.Othersareabiotic,likespace,temperature,altitude,andamountofsunlightavailableinanenvironment.Limitingfactorsareusuallyexpressedasalackofaparticularresource.Forexample,iftherearenotenoughpreyanimalsinaforesttofeedalargepopulationofpredators,thenfoodbecomesalimitingfactor.Likewise,ifthereisnotenoughspaceinapondforalargenumberoffish,thenspacebecomesalimitingfactor.Therecanbemanydifferentlimitingfactorsatworkinasinglehabitat,andthesamelimitingfactorscanaffectthepopulationsofbothplantandanimalspecies.Ultimately,limitingfactorsdetermineahabitat'scarryingcapacity,whichisthemaximumsizeofthepopulationitcansupport. Teachyourstudentsaboutlimitingfactorswiththiscuratedcollectionofresources. ViewCollection EnergyFlowThroughanEcosystem Trophiclevelsprovideastructureforunderstandingfoodchainsandhowenergyflowsthroughanecosystem.Atthebaseofthepyramidaretheproducers,whousephotosynthesisorchemosynthesistomaketheirownfood.Herbivoresorprimaryconsumers,makeupthesecondlevel.Secondaryandtertiaryconsumers,omnivoresandcarnivores,followinthesubsequentsectionsofthepyramid.Ateachstepupthefoodchain,only10percentoftheenergyispassedontothenextlevel,whileapproximately90percentoftheenergyislostasheat. Teachyourstudentshowenergyistransferredthroughanecosystemwiththeseresources. ViewCollection Biomes Abiomeisanareaclassifiedaccordingtothespeciesthatliveinthatlocation.Temperaturerange,soiltype,andtheamountoflightandwaterareuniquetoaparticularplaceandformthenichesforspecificspeciesallowingscientiststodefinethebiome.However,scientistsdisagreeonhowmanybiomesexist.Somecountsix(forest,grassland,freshwater,marine,desert,andtundra),otherseight(separatingtwotypesofforestsandaddingtropicalsavannah),andstillothersaremorespecificandcountasmanyas11biomes. Usetheseresourcestoteachmiddleschoolstudentsaboutbiomesaroundtheworld. ViewCollection BioticFactors Abioticfactorisalivingorganismthatshapesitsenvironment.Inafreshwaterecosystem,examplesmightincludeaquaticplants,fish,amphibians,andalgae.Bioticandabioticfactorsworktogethertocreateauniqueecosystem. Learnmoreaboutbioticfactorswiththiscuratedresourcecollection. ViewCollection AbioticFactors Anabioticfactorisanon-livingpartofanecosystemthatshapesitsenvironment.Inaterrestrialecosystem,examplesmightincludetemperature,light,andwater.Inamarineecosystem,abioticfactorswouldincludesalinityandoceancurrents.Abioticandbioticfactorsworktogethertocreateauniqueecosystem. Learnmoreaboutabioticfactorswiththiscuratedresourcecollection. ViewCollection HabitatsandMicrohabitats Ahabitatisanenvironmentwhereanorganismlivesthroughouttheyearorforshorterperiodsoftimetofindamate.Thehabitatcontainsallananimalneedstosurvivesuchasfoodandshelter.Amicrohabitatisasmallareawhichdifferssomehowfromthesurroundinghabitat.Itsuniqueconditionsmaybehometouniquespeciesthatmaynotbefoundinthelargerregion.Unfortunately,somehabitatsarethreatenedbypollution,extremeweather,ordeforestation.Thisputsmanyofthespeciesthatlivethereindangerandiscausingmanypopulationstodecline. Exploredifferenttypesofhabitatsandmicrohabitatswiththiscuratedcollectionofclassroomresources. ViewCollection TerrestrialEcosystem Aterrestrialecosystemisaland-basedcommunityoforganismsandtheinteractionsofbioticandabioticcomponentsinagivenarea.Examplesofterrestrialecosystemsincludethetundra,taigas,temperatedeciduousforests,tropicalrainforests,grasslands,anddeserts.Thetypeofterrestrialecosystemfoundinaparticularplaceisdependentonthetemperaturerange,theaverageamountofprecipitationreceived,thesoiltype,andamountoflightitreceives. Usetheseresourcestosparkstudentcuriosityinterrestrialecosystemsanddiscoverhowdifferentabioticandbioticfactorsdeterminetheplantsandanimalsfoundinaparticularplace. ViewCollection ExtremeMarineEcosystems DiveintoEarth'smostextrememarineecosystemsusingthismapanddoingthisactivity. ViewMap MappingMarineEcosystems Studentsinvestigatetypesofmarineecosystems,identifyexamplesoftheseecosystemsandtheircharacteristics,andlocatetheecosystemsonamapoftheworld'soceans. ViewActivity MarineEcosystems Marineecosystemsareaquaticenvironmentswithhighlevelsofdissolvedsalt.Theseincludetheopenocean,thedeep-seaocean,andcoastalmarineecosystems,eachofwhichhavedifferentphysicalandbiologicalcharacteristics. ViewArticle ViewMoreResources RelatedResources LimitingFactors   Alimitingfactorisanythingthatconstrainsapopulation'ssizeandslowsorstopsitfromgrowing.Someexamplesoflimitingfactorsarebiotic,likefood,mates,andcompetitionwithotherorganismsforresources.Othersareabiotic,likespace,temperature,altitude,andamountofsunlightavailableinanenvironment.Limitingfactorsareusuallyexpressedasalackofaparticularresource.Forexample,iftherearenotenoughpreyanimalsinaforesttofeedalargepopulationofpredators,thenfoodbecomesalimitingfactor.Likewise,ifthereisnotenoughspaceinapondforalargenumberoffish,thenspacebecomesalimitingfactor.Therecanbemanydifferentlimitingfactorsatworkinasinglehabitat,andthesamelimitingfactorscanaffectthepopulationsofbothplantandanimalspecies.Ultimately,limitingfactorsdetermineahabitat'scarryingcapacity,whichisthemaximumsizeofthepopulationitcansupport. Teachyourstudentsaboutlimitingfactorswiththiscuratedcollectionofresources. ViewCollection EnergyFlowThroughanEcosystem Trophiclevelsprovideastructureforunderstandingfoodchainsandhowenergyflowsthroughanecosystem.Atthebaseofthepyramidaretheproducers,whousephotosynthesisorchemosynthesistomaketheirownfood.Herbivoresorprimaryconsumers,makeupthesecondlevel.Secondaryandtertiaryconsumers,omnivoresandcarnivores,followinthesubsequentsectionsofthepyramid.Ateachstepupthefoodchain,only10percentoftheenergyispassedontothenextlevel,whileapproximately90percentoftheenergyislostasheat. Teachyourstudentshowenergyistransferredthroughanecosystemwiththeseresources. ViewCollection Biomes Abiomeisanareaclassifiedaccordingtothespeciesthatliveinthatlocation.Temperaturerange,soiltype,andtheamountoflightandwaterareuniquetoaparticularplaceandformthenichesforspecificspeciesallowingscientiststodefinethebiome.However,scientistsdisagreeonhowmanybiomesexist.Somecountsix(forest,grassland,freshwater,marine,desert,andtundra),otherseight(separatingtwotypesofforestsandaddingtropicalsavannah),andstillothersaremorespecificandcountasmanyas11biomes. Usetheseresourcestoteachmiddleschoolstudentsaboutbiomesaroundtheworld. ViewCollection BioticFactors Abioticfactorisalivingorganismthatshapesitsenvironment.Inafreshwaterecosystem,examplesmightincludeaquaticplants,fish,amphibians,andalgae.Bioticandabioticfactorsworktogethertocreateauniqueecosystem. Learnmoreaboutbioticfactorswiththiscuratedresourcecollection. ViewCollection AbioticFactors Anabioticfactorisanon-livingpartofanecosystemthatshapesitsenvironment.Inaterrestrialecosystem,examplesmightincludetemperature,light,andwater.Inamarineecosystem,abioticfactorswouldincludesalinityandoceancurrents.Abioticandbioticfactorsworktogethertocreateauniqueecosystem. Learnmoreaboutabioticfactorswiththiscuratedresourcecollection. ViewCollection HabitatsandMicrohabitats Ahabitatisanenvironmentwhereanorganismlivesthroughouttheyearorforshorterperiodsoftimetofindamate.Thehabitatcontainsallananimalneedstosurvivesuchasfoodandshelter.Amicrohabitatisasmallareawhichdifferssomehowfromthesurroundinghabitat.Itsuniqueconditionsmaybehometouniquespeciesthatmaynotbefoundinthelargerregion.Unfortunately,somehabitatsarethreatenedbypollution,extremeweather,ordeforestation.Thisputsmanyofthespeciesthatlivethereindangerandiscausingmanypopulationstodecline. Exploredifferenttypesofhabitatsandmicrohabitatswiththiscuratedcollectionofclassroomresources. ViewCollection TerrestrialEcosystem Aterrestrialecosystemisaland-basedcommunityoforganismsandtheinteractionsofbioticandabioticcomponentsinagivenarea.Examplesofterrestrialecosystemsincludethetundra,taigas,temperatedeciduousforests,tropicalrainforests,grasslands,anddeserts.Thetypeofterrestrialecosystemfoundinaparticularplaceisdependentonthetemperaturerange,theaverageamountofprecipitationreceived,thesoiltype,andamountoflightitreceives. Usetheseresourcestosparkstudentcuriosityinterrestrialecosystemsanddiscoverhowdifferentabioticandbioticfactorsdeterminetheplantsandanimalsfoundinaparticularplace. ViewCollection ExtremeMarineEcosystems DiveintoEarth'smostextrememarineecosystemsusingthismapanddoingthisactivity. ViewMap MappingMarineEcosystems Studentsinvestigatetypesofmarineecosystems,identifyexamplesoftheseecosystemsandtheircharacteristics,andlocatetheecosystemsonamapoftheworld'soceans. ViewActivity MarineEcosystems Marineecosystemsareaquaticenvironmentswithhighlevelsofdissolvedsalt.Theseincludetheopenocean,thedeep-seaocean,andcoastalmarineecosystems,eachofwhichhavedifferentphysicalandbiologicalcharacteristics. ViewArticle EducationalResourcesinYourInbox JoinourcommunityofeducatorsandreceivethelatestinformationonNationalGeographic'sresourcesforyouandyourstudents. signup EducationalResourcesinYourInbox JoinourcommunityofeducatorsandreceivethelatestinformationonNationalGeographic'sresourcesforyouandyourstudents. signup