1.1 Ocean Zones - University of Miami · 2018-11-15 · diagram of the ocean zones. Background An...

MarineConserva,onScience&PolicyCurriculum–2012,2015DeeringEstate.Allrightsreserved.1

FocusQuestionWhataretheoceanzonesandhowdotheydiffer?Whatkindsofanimalsliveineachzone?Whyisitimportanttolearnmoreabouttheocean?

ObjectivesStudentswillexplorethedifferentoceanzonesandthevarietyoflifefoundinthem.Studentswilllearnto:

• Identifythe5oceanzones.• Compareandcontrasttheconditionsinthedifferentzones.• Demonstrateknowledgebydrawingascalediagramofthefiveoceanzones.

This will be a project-based activity in which students will work together to draw a scalediagramoftheoceanzones.BackgroundAnocean isamajorbodyofsalinewater,whichcovers71%oftheEarth'ssurfaceformspartofthehydrosphere,Earth’s largestecosystem,hostinganestimated50-80%ofall lifeonearth, though much is unknown as 95% of this underwater world remains unexplored.4Scientists estimate that lifewith theocean evolved3billionyearsprior to lifeon land, fromsimple obligate anaerobes to the first photosynthesizing organisms to the blue whales andclown fish we recognize today.1 Some 230,000 marine species are known so far, but anestimated1-10millionspeciesremaintobediscovered.2Theseorganismshaveadaptedtothevaryingconditionsofthedifferentoceanzones.

Oceanzonesare layerswithintheoceanswithdiversephysicalandbiologicalconditionsthatsupportdistinctiveplantandanimallife.Theoceanisdividedintotworealms,thebenthicrealm(consistingoftheseafloor)andthepelagicrealm(consistingoftheoceanwaters),whicharethensubdividedintofivedifferentverticalzonesdependingondepth.

Thebenthic realmistheecologicalregionatthebottomoftheocean,and includesthesedimentlayerbelowwhichhostscrustaceans,snails,seastarsandothercreatures.Thisrealmbeginsattheshorelineandcontinuesdownwardalongthecontinentalshelf,aslopethatdropsdown to the abyssal plain at around 4,000 m. The ocean floor has submarine mountains,canyons, ridgesand trenches, and theorganisms that live in this realmvaryas thepressure,salinity,temperature,nutrientsandlightchange.3

Thephoticzonecoverstheoceansfromsurfacelevelto200metersdown,theonlyzoneinwhich sufficient sunlightpenetrates topermitphotosynthesis. Becausephotosynthesis cantakeplace,manyplantsandphotosyntheticorganismslive inthiszoneformingthefirstlink inthe food chain as primary producers. Some of these primary producers, microscopic free-floatingplantscalledphytoplankton,arethemostabundantorganismsonearthandgenerate50-90%of Earth’s oxygen. Because of this abundant food source, this zone supports 90%ofoceanlife,thoughitisthesmallestzone,featuringcoralreefs,seagrassbeds,andmuchmore.4

MarineConservationScience&Policy:OceanZones

GradeLevel:

4th–12th

SubjectAreaScienceBiologyDuration1.5Hrs

BodyofKnowledgeLifeScienceNatureofSciencePhysicalScience

BigIdeaThePracticeofScienceEarthStructures

StandardsSC.K.N.1.4Createavisualrepresentationofanobjectwhichincludesitsmajorfeatures.SC.2.L.17.2RecognizeandexplainthatlivingthingsarefoundalloverEarth,butthateachisonlyabletoliveinhabitatsthatmeetitsbasicneeds.SC.912.E.6.5Describethegeologicdevelopmentofthepresentdayoceansandidentifycommonlyfound

features.WL.K12.NM.1.4Demonstrateunderstandingofinformationsupportedbyvisuals.

Benchmarks:

MarineConserva,onScience&PolicyCurriculum–2012,2015DeeringEstate.Allrightsreserved.2

BackgroundMost lightremainsinthesunnypho,czone,withfewrayspenetra,ngthemesopelagic,or twilight zone, which extends from 200 to 700-1000meters. This zone is significant in thediurnal(daily)ver,calmigra,onofnumerousspeciesofsmallorganismsupwardstothepho,czone at night, amovement ocen referred to as the greatestmigra,on on earth in terms ofbiomass. This movement makes the ocean the world’s largest carbon sink and essen,al tomi,ga,ngclimatechange.

Thebathyal,ormidnight,zoneisachill4oC(39oF)extendingininkydarknessfrom1,000to4,000meters. Thiszonemarksthebeginningoftheapho,c,orno light, zone,andIt issodarkthatsomespeciesdon’tevenhaveeyes,whileothershaveadaptedtransparentskin,slimybodiesor evenbioluminescence to survive.This zone is the feedinggroundofmanywhales,squid,andoctopuses,aswellasmanyunusualcreatures.

From 4,000 to 6,000 meters deep, the abyssal zone is characterized by perpetualdarkness,withtemperaturesanalmostfreezing2-3oC(35oF).Fissuresintheoceanfloorcreatehydrothermalventswithboilingtemperatures,lethallevelsofhydrogensulfidesandpressuresthatwouldcrushahumaninstantly.Creaturesinthiszonearemostlyscavengersthatdependuponmarinesnowfornutrients,sinkingorganicmaherthatincludesdeadordyingplantsandanimals.Thoughcondi,onswerethoughttobetoohos,letosupportlife,scien,stsusingtheminisubmarine Alvin in 1977, discovered an extraordinary abundance of creatures in thesedepths,rangingfromtheten-footlongtubeworms,clamsoverafootwide,wrigglingspagheiworms,andevenGiantsquid.Thisextraordinaryexuberanceactuallystemsfromthedeepseavents, where ,ny, unassuming bacteria are conver,ng the toxic compounds into sustenanceand thereby providing the means to support a food chain independent of light, oxygen oranythingelsenormallyassociatedwithlife.Thissystemissupportedbychemosynthesisratherthanphotosynthesis,andcouldhelpusunderstandthepossibili,esonlifeonotherplanets.

The hadal zone, named acer the underworld realm of Hades, is found in the deepesttrenchesoftheoceanfromdepthsof6,000meterstobohomoftheocean.Foodissparseandthepressurecanreach11,000p.s.i., theequivalentofahumantryingtohold50 jumbojets.Becauseof theextremepressure, lownutrientavailabilityand lackof light, this zone isonlyspareselypopulatedbycreaturesadaptedtowithstandtheharshcondi,ons,includingjellyfish,viperfish,seacucumbersandtubeworms.

Thoughthesezonesaredis,nguishedbytheirdifferences,theyareallinterconnectedbycurrents and each is an important habitat for a variety of organisms. Likewise, the oceansprovidetheairwebreathe,thefoodweeat, life-savingmedicines, jobs, recrea,onandmanyother necessi,es. Over 95% of the ocean remains unexplored, and we must preserve thiswondrousworldfortheuntolddiscoveriesoffuturegenera,ons.4

SupplementalResources1-“HistoryofLifeonEarth.”BBCNature.hhp://www.bbc.co.uk/nature/history_of_the_earth2-“TheCensusofMarineLife.”SmithsonianNa,onalMuseumofNaturalHistory.hhp://ocean.si.edu/census-marine-life3-“TheDeepSea.”MarineBio.hhp://marinebio.org/oceans/deep/4-“NamethatZone!”NationalOceanicandAtmosphericAdministration(NOAA).https://coast.noaa.gov/data/SEAMedia/Presentations/PDFs/Grade%203%20Unit%202%20Lesson%201%20The%20Open%20Ocean.pdf

OceanZones:Thedivisionsoftheoceanfromthesurfacetotheoceanfloor,whichvarybydepth,pressure,light,andnutrients.BenthicRealm:Thisrealmbeginsattheshoreandextendsalongthecontinentalshelfandtheoceanfloor,shapedbysubmarinemountains,ridgesandtrenches

PelagicRealm:Theopenpartoftheocean(orlakes)thatisneithernearthebottomnortheshore.MesopelagicZone:Thezoneextendingfrom200to700-1000mdeep,onlydimlylitbuthosttomillionsofmicroorganisms.

BathyalZone:Thiszoneiscold,dark,andrangesfrom1,000-4,000mdeep.

AbyssalZone:Extendingfrom4,000to6,000mdeep,thiszoneisperpetuallydarkandcoldbutsurprisinglyhostsawidearrayoforganisms.

HadalZone:Divingfrom6,000mtothebottomofthedeepestoceantrench,thiszoneischaracterizedbyextremecoldandpressure,populatedbyextremophiles.

Vocabulary:

MarineConservationScience&Policy:OceanZones

MarineConserva,onScience&PolicyCurriculum–2012,2015DeeringEstate.Allrightsreserved.3

Activity:IllustratingtheOceanZonesMaterials

• Fourlargebutcherorposterpapersheets• Multicolormarkers,crayonsorcoloredpencils• Largemeterstickorruler• Picturesofmarinelifefromdifferentdepths(canbepre-gluedontoindexcardsto

strengthen)• Glueordouble-sidedtape• Tapeforhangingthediagram

Procedure

1. Havestudentsdivideintofourgroupsandlaytheirpaperonthefloor.2. Usingthemeterscaleoneithersideofthediagram,havestudentslabelfrom0mat

theoceansurfaceto6,000manddeeperanddrawsomeofthegeologicalstructuresoftheoceanbasin(i.e.con,nentalshelf,slope,riseandcon,nentalplain).

3. Atthetopofthediagram,havestudentsdrawthesurfaceoftheoceanandstructuresfoundatthislevel(i.e.coralreefs,asailboat,aleapingdolphin).

4. Atthebohomofthediagram,havestudentsdrawsomefeaturesofthebenthicrealm,(i.e.trench,hydrothermalvent).Labelsandfeaturestoincludeonthediagram:Pho,c(sunlit)zone Shoreline AbyssalplainApho,c(nolight)zone Sealevel RicvalleyBenthicrealm Coralreef Con,nentalshelfPelagicrealm Mid-oceanridge Con,nentalslopeBathyalzone Trench Con,nentalriseAbyssalzone Hydrothermalvent SubmarinecanyonHadalzone Subfloorsediment

5. Havestudentsplacedifferentorganismsattheirappropriatedepthsintheocean.6. Groupsshouldpresenttheirwork.Encouragediscussionbyaskingwhichzoneswould

theyliketovisit,whichzonehoststhemostinteres,ngorganisms,whyoceanexplora,onisimportant,etc.

WorksheetAnswerKey

1. Fromshallowtodeep:pho,c–mesopelagic–bathyal–abyssal–hadal2. Oceanography,five3. Pho,c,photosynthesis4. Submarinetrenches,anglerfish

OceanZones:Thedivisionsoftheoceanfromthesurfacetotheoceanfloor,whichvarybydepth,pressure,light,andnutrients.BenthicRealm:Thisrealmbeginsattheshoreandextendsalongthecontinentalshelfandtheoceanfloor,shapedbysubmarinemountains,ridgesandtrenches

PelagicRealm:Theopenpartoftheocean(orlakes)thatisneithernearthebottomnortheshore.Studentswillinvestigatethehistoryandlimitationsofoceanexploration,andjustifyfutureexplorationsbysummarizingandanalyzinganarticle.Theobjectiveisforstudentstounderstandhowdeeptheoceanisandwhyorganismsarelimitedtocertaindepths.WhyistheoceanmostlyunexploredandwhatpreventshumansfromdivingusingSCUBAtoexplorethedeepocean?Whattechnologiesarebeingdevelopedtopushthelimitsofoceanexploration?Studentswillcompletetheoceanzonesworksheetafterclass,andshouldwriteasciencejournalentryansweringthefollowingprompt:Ifyoucouldvisitanyoceanzone,whichwoulditbeandwhy?Howwouldyougetthereandwhatwoulddoyouthinkyou’lldiscover?Remembertousethefivesenseswhendescribingyourtrip.

ExtensionActivity:

Assessment:

VocabularyContinued:

MarineConservationScience&Policy:OceanZones

MarineConserva,onScience&PolicyCurriculum–2012,2015DeeringEstate.Allrightsreserved.4

MSCP

OceanZones:

2.Thescienceofstudyingtheoceaniscalled________________,andthesescientistshavedividedtheoceaninto

_________________zones.

3.The__________________zonehostsphytoplanktonwhichproducesmostoftheworld’soxygenthrough

_____________________.

4.Inthe___________________ofthehadalzone,somespecieslikethe_______________usebioluminescence

tolureintheirprey.

WordBank:anglerfish-photosynthesis-submarinetrenches–oceanography–photic–five

Theoceanisdividedintofivezones:thephoticzoneisthesunnytoplayerwhichsupportsphotosynthesisandhostsmostoftheocean’sorganisms;themesopelagiczonebegins200mdeepandishometomanymicroorganisms;thebathyalzoneisdarkasmidnightandiswheremanywhalesgotofeed;theabyssalzoneisalmostfreezingcoldandmanyfantasticcreatureslivehere;andfinallythehadalzonedelvesintothedeepestoceantrenches.

1.Pleaselabelthezones,colorthemaccordingtolightconditions,anddrawsomeorganismsinthezonethatistheirhome.