Cycling of Matter in Earth's Spheres

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3.2 Cycling of Matter in Earth’s Spheres

Biosphere 2 is a research facility located in Arizona.

CAN YOU SOLVE IT?

The curious-looking buildings shown in the photo above are part of a research facility located in Arizona called Biosphere 2. The tightly sealed glass and steel structure currently serves as a place where scientists study Earth’s ecosystems to better understand carbon and oxygen cycles, coral reef health, water recycling, and more. On September 26, 1991, eight research scientists began a two-year adventure living in Biosphere 2. The researchers, known as “Biospherians,” were completely sealed off from the outside environment to simulate living in a closed ecosystem. But the results of the experiment were unexpected. The Biospherians had to cope with inadequate food, decreasing oxygen levels, and increasing carbon dioxide levels. The imbalances resulted in many plants and animals dying, providing evidence that ecosystems are much more complex and dynamic than originally thought.

PREDICT Why did problems with low oxygen levels and increasing carbon dioxide levels develop in Biosphere 2? How would you solve these problems? © Houghton Mifflin Harcourt Publishing Company • Image Credits: ©James Marshall/Corbis

Evidence Notebook As you explore the lesson, gather evidence for how matter and energy change form as they cycle through ecosystems.

Lesson 2 Cycling of Matter in Earth’s Spheres 159 DO NOT EDIT--Changes must be made through “File info” CorrectionKey=CA-B

EXPLORATION 1

Matter Cycles Through Ecosystems

Earth is an open system in terms of energy, as it constantly gains energy from the sun. In contrast, Earth is a closed system in terms of matter. All of the matter on Earth has more or less been here for billions of years. Matter and energy cannot be created or destroyed, only transformed into other forms.

PREDICT Matter and energy move through ecosystems between different organisms. How does matter travel through an ecosystem and through Earth’s spheres?

Energy and Matter in the Earth System

The Earth system includes all of the matter, energy, processes, and cycles within Earth’s boundary with space. Energy from the sun drives the cycling of matter in Earth’s spheres and in the many ecosystems within those spheres. Producers use only about one percent of the sun’s energy that enters Earth’s atmosphere.

Math Connection

Solar Radiation FIGURE 1: Earth’s atmosphere absorbs and reflects energy. When solar radiation enters Earth’s atmosphere, about 23 percent is absorbed in the atmosphere and about 48 percent is absorbed at the surface. The rest is reflected back into space. 23% SOLVE If energy is conserved, what percent of the solar energy should be reflected back into space?

a. 71% c. 100% 48% b. 12% d. 29%

Like energy, matter in the Earth system cycles within and among Earth’s spheres: the atmosphere, geosphere, hydrosphere, biosphere, and even the anthrosphere. A relatively

small amount of matter is lost into space from the very top of the atmosphere, but © Houghton Mifflin Harcourt Publishing Company • Image Credits: NASA Johnson Space Center scientists generally think of the Earth system as closed in terms of matter.

Collaborate Discuss this question with a partner: How do you think Earth’s ecosystems would be different if more or less solar radiation was reflected by the atmosphere?

160 Unit 3 Ecosystem Interactions and Energy Flow DO NOT EDIT--Changes must be made through “File info” CorrectionKey=CA-B

EXPLAIN Use the correct terms to complete the statement about Explore Online Earth’s spheres. FIGURE 2: This glass globe models the atmosphere biosphere geosphere hydrosphere Earth system. Energy from the sun fuels the cycling of matter. For example, water in the evaporates to the . Water returns to Earth’s surface, or the , as precipitation. Organisms in the use water to carry out cell processes. Matter changes form as it cycles through the Earth system, but like energy, it cannot be destroyed. For example, organisms metabolize food using chemical reactions. These reactions break bonds and form new chemical bonds among the same atoms to make new compounds. An organism can use these new compounds for growth and cell processes. Some matter is excreted as waste, which is recycled in the environment. The total amount of matter in the system remains unchanged. Using food webs and pyramid models, you can show how matter cycles through different trophic levels in an ecosystem. As one organism consumes another, that matter is transferred into higher trophic levels. When organisms die, their matter is cycled back through lower trophic levels. In this way, no new matter is created, but matter continually moves through and between ecosystems.

The Water Cycle

Scientists model specific cycles to better understand the cycling of matter in the Earth system. The hydrologic cycle, also known as the water cycle, is the pathway of water on Earth.

ANALYZE Water moves by different processes and is stored in reservoirs. Determine whether each item is a reservoir or a process.

clouds condensation (clouds) reservoir | process precipitation

precipitation transpiration evaporation reservoir | process evaporation

evaporation runoff reservoir | process

freshwater lake lake ocean © Houghton Mifflin Harcourt Publishing Company reservoir | process groundwater

percolation into soil

Lesson 2 Cycling of Matter in Earth’s Spheres 161 CorrectionKey=CA-B DO NOT EDIT--Changes mustbemade through “File info” 162 Weathering Earth’s Cyclesand Hands-On Lab in theEarthsystem. interactions betweenwaterandrock apply yourknowledgetoinvestigate can dissolvecertainsubstances,then an investigationtoseehowwater Explor e Online Unit 3Ecosystem Interactionsand EnergyFlow Plan andconduct oxides (NOandN dioxide, andinverysmallquantitiesasothergasessuchozone (O oxygen thatallorganismsneed.Oxygenisalsofoundintheatmosphereaspartofcarbon gases such asoxygenandcarbondioxideionssuchas bicarbonate(HCO think aboutoxygen,youmayofoxygengas(O and atmosphere bywayofphotosynthesis,respiration,anddecomposition.Whenyou Most oftheoxygencyclingonEarthoccursamongbiosphere,hydrosphere, The OxygenCycle are broken,andatomsrearrangedintonewmolecules. flows betweenreservoirswhereitisstoredforaperiodoftime.Asmattercycles,bonds heat fromwithinEarthprovideenergythatdrivesthesecycles.Thematterincycles elements cyclethroughtheEarthsystem,ecosystems,andorganisms.Thesun as carboninteractchemicallytheycyclethroughEarth’sspheres.Likewater,these Many elementsareessentialforthefunctioningandgrowthoforganisms.Elementssuch Cycles ofMatter onEarth MODEL

Select thecorrectlabelstocompletemodelofoxygencycle. does notchange,whyarethereconcernsaboutglobalfreshwatershortages? Collaborate process startsagain. streams orrivers.Waterendsupinareservoirwhereitisstoreduntilthe as rain,snow,orhail.Precipitationseepsintothegroundflows into clouds.WaterthenfallsbacktoEarthintheformofprecipitation,such transpiration. Aswatervaporrisesintotheatmosphere,itcoolsandcondenses reservoirs suchastheoceanandtoevaporatefromplantleavesthrough In thehydrologiccycle,heatfromsuncauseswatertoevaporate example ofaprocessthatmoveswaterbetweenreservoirs. a glacier,orforshorterperiodsoftime,suchasincloud.Precipitationisan molecules mightbestoredinareservoirforlongperiodoftime,suchas processes. Areservoirisanylocationwherecyclingmatterstored.Water Within thehydrologiccycle,watermovesbetweenreservoirsbydifferent 2 O). Intheoceans,it ispartofwater(H cellular respiration With apartner,discussthisquestion:IfthetotalamountofwateronEarth

O 2 CO 2 2 ) intheatmosphere,formof 2 photosynthesis O) butalsooccursasdissolved 3 ) andnitrogen 3 – ).

© Houghton Mifflin Harcourt Publishing Company nitrogen cycletakesplacebelowground. ammonia, nitrite,nitrate,andotherchemicalsthatorganismscanuse.Muchofthe use. Bacteria,whichareinvolvedinmanystepsofthenitrogencycle,fixinto The nitrogenmustbefixed,orincorporatedintoothermoleculesthatorganismscan most organismsarenotabletousenitrogeninthisformbuildorganicmolecules. by thesebacteriaistransformed intoammonium(NH Other nitrogen-fixingbacteria livefreelyinthesoil.Theammoniareleased outgrowths, callednodules, on therootsofplantssuchasbeansandpeas. perform thistask.Somenitrogen-fixingbacteriaonland liveinsmall they donotuseoxygen.Inaquaticecosystems,afewtypes ofcyanobacteria which meanstheyuseoxygen.Otherbacteriaareanaerobic, whichmeans through aprocesscallednitrogenfixation.Someofthese bacteriaareaerobic, Certain typesofbacteriaconvertgaseousnitrogenintoammonia (NH About 78percentofEarth’satmosphereiscomposednitrogengas(N The NitrogenCycle because waterisnecessaryforphotosynthesis. interacts withothercycles.Forexample,thewatercycleoxygencycle, biological molecule,includingcarbohydrates,fats,and proteins.EachcycleonEarth Oxygen thatistakenin byplantsandanimalsconvertedintoalmosteverytype of into nitrite(NO is usedbynitrifyingbacteria asanenergysource.Thesebacteriachangeammonium hydrogen ionsfoundinacidic soil.Plantstakeupsomeammonium,butmost atmosphere tothebiosphere andbackagain. FIGURE 3: Evidence Notebook explain howitrelatestoprocessesintheoxygencycle. carbon dioxidereacheddangerouslevels.Describeapossiblesolutiontothisproblem,and The nitrogen cycleismadeupofmanyprocesses thatmovenitrogen from the denitrification 2 – ) andthennitrate (NO producers In theBiosphere2project,oxygenlevelsdecreasedovertimeand consumers assimilation decomposers nitrate 3 – ) throughaprocess callednitrification.

nitrification atmospheric nitrogen nitrite 4 + ) bytheadditionof ammonification soil ammonium 3 fertilizer factory ) Lesson 2 Cycling of MatterinEarth’s Spheres leaching 2 ). However, Nitrogen Fixation of legumerootnodules. bacteria byobservingpreparedslides Investigate theroleofnitrogen-fixing ammonia

nitrogen fixation Hands-On Lab Explor e Online

163 CorrectionKey=CA-B DO NOT EDIT--Changes mustbemade through “File info” 164 relationship withplantsinthelegumefamily. FIGURE 4: a

Unit 3Ecosystem Interactionsand EnergyFlow (colored SEM). pea plantnodules bacteria thatlivein are nitrogen-fixing Rhizobia bacteria Energy andMatter Rhizobia bacteriahaveasymbiotic the ecosystemaffectnitrogen cycle? plants arenotlefttodecompose intothesoil.Howdoesremovinglegumesfrom APPLY lakes, swamps,andoceansinaprocesscalledleaching. the soil.Nitratesinsoilmaybemovedbywater,eventuallysettlingatbottomof combination ofnitrogenmonoxidewithrainwaterformsnitrates,whichareabsorbedby Nitrogen recombineswithoxygenintheair,formingnitrogenmonoxide.The lightning. Energyfromlightningbreaksapartnitrogenmoleculesintheatmosphere. of fertilizer.Somenitrogenalsoentersthesoilasaresultatmosphericfixationby of bacteria,butitcanalsooccurthroughindustrialprocessessuchastheproduction Nitrogen fixationcanoccurthroughbiologicalprocessescarriedoutbyspecialtypes releasing nitrogengasbackintotheatmosphereasawasteproductviadenitrification. in aprocesscalledammonification.Denitrifyingbacteriausenitrateasanoxygensource, excretions ordeadanimalandplantmatter,nitrogenisreturnedtothesoilasammonium the cycleasanimalseatplantoranimalmatter.Whendecomposersbreakdown them intoorganiccompoundssuchasaminoacidsandproteins.Nitrogencontinuesalong Nitrates releasedbysoilbacteriaaretakenupplantsthroughassimilation,whichconverts nitrogen canhavesuchalargeimpactonlife. Using evidencefromthenitrogencycle,explainhowmicroscopicfixationof

EXPLAIN b

Legumes areoftenplantedandharvestedascrops.When thishappens,the Scale, Proportion, andQuantity

of theplant. develop ontheroots Pea plantnodules

Bacteria aremicroscopicorganisms,buttheyessentialtolifeonEarth. atmosphere asnitrogengas. release someofthatnitrogenbackintothe molecules intoothernitrogencompoundsand dies. Then,decomposersconverttheammonia and verylittleisreleasedintothesoiluntilplant ammonia madebythebacteriaiskeptplant into ammonia,whichtheplantabsorbs.Mostof bacteria and,inreturn,thefixnitrogen The plantprovidesessentialnutrientstothe bacteria liveinthenodulesonrootsoflegumes. particularly thoseinthelegumefamily.Rhizobia close relationship,withcertaintypesofplants, Nitrogen-fixing bacterialivesymbiotically,orin Rhizobia Bacteria

© Houghton Mifflin Harcourt Publishing Company • Image Credits: (l) ©Steve Gschmeissner/Science Source (r) ©Dr. Jeremy Burgess/Science Source DO NOT EDIT--Changes must be made through “File info” CorrectionKey=CA-B

The Phosphorus Cycle Phosphorus is an important element for living things. It is a component of phosphate groups in ATP, DNA, and phospholipids in cell membranes. Phosphorus occurs in the form of phosphate salts found in ocean sediments and rocks. Geologic processes expose these rocks, and water and wind break them down, making them available to plants and animals.

FIGURE 5: The phosphorus cycle interacts with the rock cycle through processes such as geologic uplift and weathering.

phosphate mining phosphate rocks

weathering

fertilizer soil leaching runoff

geological uplift producers excretion and decomposition consumers

dissolved phosphates

phosphate rocks sedimentation

Weathering of phosphate rocks by rain releases phosphate compounds in soil and water. On land, plants can take up phosphate compounds from the soil, and consumers gain phosphorus by eating the producers. Decomposers then return phosphorus to the soil and water when they break down the organic matter and wastes of the producers and consumers. Water can transport phosphorus to aquatic ecosystems through runoff and leaching. Phosphorus compounds dissolve into phosphates, where they can be taken up by algae and then consumed by other aquatic organisms. Some dissolved phosphates settle at the bottom of oceans in a process called sedimentation, becoming phosphate rocks over millions of years. Certain geologic processes expose the phosphate rocks at the bottom of the ocean to the atmosphere. The rocks then undergo weathering, releasing phosphate compounds back into the ecosystem and continuing the phosphorus cycle. Humans also introduce phosphates into the ecosystem by mining them to make fertilizers and cleaners. Excess phosphates from human activities can enter aquatic ecosystems through runoff and leaching. Very little phosphate is naturally available in most bodies of water, and any increases can lead to significant changes in the ecosystem.

© Houghton Mifflin Harcourt Publishing Company INFER Which statements are true about the phosphorus cycle? Select all correct answers. a. Phosphate flows from the atmosphere to the geosphere. b. Phosphorus is stored in only abiotic reservoirs. c. Weathering releases phosphate from rocks. d. Phosphate is taken up by producers in aquatic ecosystems.

Lesson 2 Cycling of Matter in Earth’s Spheres 165 CorrectionKey=CA-B DO NOT EDIT--Changes mustbemade through “File info” 166 FIGURE 6: Unit 3Ecosystem Interactionsand EnergyFlow Processes suchasphotosynthesis,cellularrespiration, andcombustiondrivethecyclingofcarbon. carbon reservoirs. These processesareveryslow,takingmillionsofyears,but theyformextremelylarge in theprocessesofsedimentationandburialtoformdifferent typesofsedimentaryrock. algae andphytoplanktonconvertitduringphotosynthesis. SomedissolvedCO absorb andholdlargeamountsofcarbon.Carbonenters theaquaticbioticcyclewhen Carbon dioxidediffusesintotheoceanfromatmosphere. Oceansarecarbonsinksthat it, releasinglargeamountsofcarbonbackintotheatmosphere. becomes fossilfuel.Sincethe1800s,humanshaveextractedthiscarbonand combusted the burialprocessstoresthatcarboninEarth’scrustwhere, overmillionsofyears,it Some ofthecarboninorganicmattermaybecomefossilized. Undercertainconditions, the atmospherethroughcellularrespiration.Carbonisalsoreleasedintosoil. consumers die,decomposersbreakdowntheorganicmatterandreleasecarbonbackinto and releasingsomebackintotheatmospherethroughcellularrespiration.When consumers eatproducers,theyobtainthecarbon,storingsomeofitintheirtissues organisms incorporatethecarbonintocarbohydratestostoreintheirtissues.When Producers removeCO compounds inrocksareallcarbonreservoirs. the atmosphere,fossilfuelssuchasoilandcoal,deadmatterinsoil,chemical also storedinabioticcomponentsoftheEarthsystem.Forexample,carbondioxide Carbon ispresentinmostchemicalcompoundsthatmakeuplivingthings. The CarbonCycle consumers photosynthesis burial Evidence Notebook another? Howcan achangeinonecycleaffectallof theothercycles? producers decomposers Evidence Notebook this, andhowdoesitrelatetothenitrogenphosphoruscycles? nutrients, researcherstreatedthewaterbyrunningitovermatsofalgae.Whydidtheydo fossil fuels extraction respiration cellular 2 from theatmospherethroughphotosynthesis.Photosynthetic How dothehydrologiccycleand differentcyclesofmatterrelatetoone atmospheric CO When thewateratBiosphere2becamepollutedwithtoomany combustion

2 sedimentary rock exchange consumers dissolved CO producers decomposers 2 sedimentation 2 is used

© Houghton Mifflin Harcourt Publishing Company atmosphere thatkeepEarth’stemperatureswarmenoughtosupportlife. in andout.Carbonisfoundthetissuesofalllifeforms.Italsopartgases coal, itisdissolvedinseawater,andappearsgaseousformtheairthatwebreathe Carbon appearsinmanydifferentformsEarth’ssystems.Itisfoundsolidform Cycle Carbon the Modeling EXPLORATION 2 if photosynthesisstopped? Earth systemthanprocessesthatmovecarboninandoutofthegeosphere. few hundredyears.Therefore,theseprocessescanhaveamoreimmediateimpactonthe carbon betweenthehydrosphere,atmosphere,andbiosphereworkonatimescaleof the timescaleandrateatwhichtheseprocessesoperate.Naturalthatmove The impactoftheprocessesthatcyclecarbonbetweenEarth’ssystemsdependson The CyclingofCarbon PREDICT FIGURE 7: Cambridge University Press.Adaptedandreproducedby permissionofIntergovernmentalPanel onClimateChange. Credit: AdaptedfromClimateChange2007:WorkingGroup I:ThePhysicalScienceBasisbyDenmanetal.Copyright©2007 by

Different processes function tocyclecarbononlandandintheoceans. How wouldtheprocessesandreservoirsofcarboncyclechangeovertime lan 2300 d biomass GtC fo 6.4 GtC/y ssil fuels 1.6 G la ch nd use anges tC/y 119.6 G resp atmos 597 GtC ira tion tC/y phere p hot 120 G Lesson 2 Cycling of MatterinEarth’s Spheres osynthesis tC/y 7 esca 0.6 G 150 G pes tC/y 900 G tC surf tC surf dissolves 7 0 G ace sediment tC/y na hu ace ocean tura man a l pro ctiv cesses ities 167 CorrectionKey=CA-B DO NOT EDIT--Changes mustbemade through “File info” 168 Unit 3Ecosystem Interactionsand EnergyFlow and predictfuturechanges. and thedeepocean.Differentmodelscanbeusedtogethertoexplain currentchanges the entireoceanasonereservoir,whileothersdivideitupintotworeservoirs: thesurface included withbiomass,whileinothersitissediment.Somemodels show because reservoirscanbegroupeddifferently.Forexample,insomemodels,soil is varying results.Theamountsalsochangeovertime.Numbersinmodelscanalso differ, It isextremelydifficulttomeasurecarbonprecisely.Differenttypesofmeasurements give Measuring Carbon one billiontons. year ofcarbonmovingintotheatmospherefromhumanactivities.Agigatonisequalto biosphere andgeosphere.ThemodelinFigure7showsanadditional8gigatons(Gt)per Human activitiesmovecarbonintotheatmospherefromlong-termstoragein wood inforests. balance eachother,butmovesomecarbontowardlongertermreservoirs,suchasthe 7. Thecurvedarrowsonthelandshowthatphotosynthesisandrespirationroughly dioxide. ThisexchangeofgasesisshownbythecurvedarrowsaboveoceaninFigure The oceanandtheatmospherearealsoconstantlyexchanginggases,includingcarbon plants, animals,andsoilorganismssuchasfungibacteria. that cyclecarbonbetweensystems.Theseprocessesareconstant,cyclingthrough In thebiosphere,photosynthesis,cellularrespiration,anddecompositionareprocesses shrinking? energy helpyoutounderstandwhetherdifferentcarbonreservoirsaregrowingor also releasecarbontotheatmosphere. the bodycausesreleaseofcarbontoatmosphere.Fossilfuelsthatareburned Energy fromthesunallowsplantstousecarbonmakebiomass.burnedin Carbon ismatter,andenergyneededtomovethismatterinthecarboncycle. EXPLAIN Energy andMatter

How cananunderstandingoftheinteractionsbetweenmatterand

© Houghton Mifflin Harcourt Publishing Company water andhowthataffectstheshellsofsomemarineorganisms. will bothexploretheimpactofincreasedconcentrationsdissolvedCO Record youranswerinEvidenceNotebook is thishappening?HowdoesthegenerationofCO more difficulttimebuildingshells,andsomeexistingshellsbreakdowneasily.Why organisms—specifically thosethathaveexoskeletonsofcalciumcarbonate.Somea The increasedlevelsofCO • • • • • • • • • • • • How doesincreasedconcentrationofdissolvedCO SAFETY INFORMATION MATERIALS MAKE A CLAIM Wash yourhandswithsoapandwaterimmediatelyafter completingthisactivity. from watersourcestopreventshock. Use onlyGFIprotectedcircuitswhenusingelectricalequipment, andkeepaway Use cautionwhenworkingwithglassware,whichcanshatter ifdroppedandcutskin. out throughthestraw. Do notinhaleandsucktheindicatorsolutionupstraw. Onlyexhaleandblow Keep burningcandlesawayfromcombustiblematerials to avoidcausingafire. Use cautionwhenworkingwithheatingsources.Theycan burnskin. Use cautionwhenworkingwithcausticchemicals(acids).Theycanburnskin. slip/fall hazard. Immediately pickupanyitemsdroppedonthefloorsotheydonotbecomea gloves duringthesetup,hands-on,andtakedownsegmentsofactivity. Wear indirectlyventedchemicalsplashgoggles,anonlatexapron,and beaker, 200mL (optional) baking sodaandvinegar apron, nonlatexgloves splash goggles,nonlatex indirectly ventedchemical Hands-On Lab Ocean Acidification 2 intheatmosphereseemtohaveanadverseeffectonmarine • • • device withInternetaccess (optional) candle andmatches solution, 50mLpertest bromothymol blueindicator

2 2 affectthepHofwater?Inthislab,you leadtoincreasedacidityofwater? • • thermometer • straw • • • yeast (optional) sodium chloride pH probe(optional) heat source Lesson 2 Cycling of MatterinEarth’s Spheres 2 ontheacidityof

indirectly vented chemical splash goggles 169 CorrectionKey=CA-B DO NOT EDIT--Changes mustbemade through “File info” 170 Unit 3Ecosystem Interactionsand EnergyFlow 3. 4. increased CO water? Howisrisingglobaltemperaturerelatedtotheamount ofCO of CO Evidence water? Wasyourpredictioncorrect? 2. 1. Part B 3. Reasoning Claim Write aconclusioninyourEvidenceNotebookthataddresseseachofthepointsbelow. 2. 1. Part A affect theabilityofCO DRAW CONCLUSIONS CARRY OUT THE INVESTIGATION your experimenttoinvestigatetheeffectofsalinityonabilityCO The focusofthisinvestigationistheimpactoceanacidificationonmarinelife.Adapt on pH. this temperatureriseontheabilityofCO risen inthelast100yearsandthenadaptyourexperimenttoinvestigateeffectof can alsoaffectmarinelife.Researchhowmuchtheaverageoceantemperaturehas Rising globaltemperaturesandtheparallelriseinaverageoceantemperature the water.InyourEvidenceNotebook,explainhowyouwillalterexperiment. As agroup,decidewhichmethodofCO forsuggestions. Notebook, explainhowyouwillalteryourexperiment. use theInternettoresearchideasforsimpleCO with atleastthreedifferentwaysthatCO CO experiment thatusesanindicatorsolutionorapHprobe(ifavailable)toexplorehow Think abouteventsthatgenerateCO in yourEvidenceNotebook. yellow indicatesalowerpHandgreenhigherpH.Recordthecolorsolutionchangedto Stopexhalingonceacolorchangehasoccurred.Colorswillrangefromgreentoyellow— Exhale intothestrawtoaddCO Notebook. Pour 50mLofindicatorsolutionintoabeaker.RecordthecolorinyourEvidence Evidence Notebook understand acomplex modelthatshowschangesin carbondioxideconcentrationin theatmosphere? 2 2 affectspH.InyourEvidenceNotebook,explainhowyouwilltesttheeffectofCO todissolveinwaterandhowdoesthataffectpHlevels? How doestemperature HowdoesincreasedconcentrationofdissolvedCO Use thesequestionstoguideyouranswer.Howdoessalinity affecttheability How istheCO 2 affecttheshellsofsomemarineanimals? 2 todissolveinwaterandhowdoesthataffectpHlevels? How canunderstandingasimplemodel ofthecarboncyclehelpyou 2 levelintheatmosphererelatedtoamountofCO 2 fromyourbreathtothebeaker.

2 . Brainstormwithyourgrouptocomeup 2 generationyouwilluse.Then,designan 2 2 todissolveinthewater.InyourEvidence couldbegeneratedinyourlab.Ifnecessary, 2 generation,oraskyourteacher 2 leadtoincreasedacidityof 2 inwater?Whydoes 2 todissolvein 2 in 2

© Houghton Mifflin Harcourt Publishing Company • Image Credits: (t) ©Guido Cozzi/Atlantide Phototravel/Corbis (b) ©Comstock Images/Jupiterimages/Getty Images ultraviolet raysfoundinsunlight. upper atmosphere.There,itactsasashieldprotectingEarth’s biosphereagainstharmful to humanhealthandecosystemfunctions.However,ozone alsoexistsnaturallyinthe nitrogen dioxideandoxygentendstostayclosetheground, whereitcanbeharmful and energy? Island? Howdidtheychangetheisland’snaturalcyclingofmatter inhabitants areamajortouristattraction. lives ontheisland.Thestonemonumentsplacedbyfirst Easter Islandersdisappeared.Today,asmallpopulationofpeople was lost.Withnofoodandtheislandresourcesnearlygone, soil washedaway,andhabitatfortheisland’sanimalpopulations trees. Withouttrees,therewasnowoodforshelterorboats,the they couldgrowback,andeventuallytheislandwasleftwithno lumber andforbuildingboats.Theforestswereclearedfasterthan quickly overthenext1000years,cuttingdownforestsfor inhabited between400CEand700CE.Thehumancolonygrew Easter Island,locatedinthesoutheasternPacificOcean,wasfirst Human Impact on Earth’s Cycles EXPLORATION 3 oxygen toproduceozone,O by fossilfuelemissions.Thenitrogendioxideinsmogreacts with caused bytheinteractionofsunlightwithpollutantsproduced chemicals thatpollutetheair.Smogisatypeofairpollution releases carbondioxide,methane,nitrousoxide,andother contain carbon,nitrogen,andphosphorus.Burningfossil fuels produced byburningfossilfuels,suchasgasolineandoil that The mostcommonairpollutioncomesfromthewasteproducts can disruptecosystemfunctions. immediate ordelayed,buttheseeffectsmayaddupovertimeand ecosystem functions.Theharmfuleffectofthesepollutantscanbe and manyofthesechemicalscannotbeintegratedintonormal Each yearhumansaddsyntheticchemicalsandmaterialstoEarth, nitrogen intheEarthsystemwouldbearelativelysteadystate. Without humanactivity,thecyclingofcarbon,phosphorus,and Air Pollution PREDICT Evidence Notebook atoms arerearrangedduringcycles ofmatterasaresulthumanactivities.

What effectdidthehumanpopulationhaveonEaster 3 . Theozoneproducedbyreactionsof As youread,recordevidencetosupport orrefutetheideathat

Lesson 2 Cycling of MatterinEarth’s Spheres open areas ofEasterIsland. to airpollution. FIGURE 8: FIGURE 9: These stonefigures standinthe Engine combustioncontributes 171 CorrectionKey=CA-B DO NOT EDIT--Changes mustbemade through “File info” L. Kell 6-29-16 bi_cnlese539273_39a 172 Unit 3Ecosystem Interactionsand EnergyFlow Earth’s atmosphere. two examplesofhumanactivitiesthatleadtoincreasedcarbondioxidelevelsin removed byotherprocesses.Combustingfossilfuelsandclear-cuttingforestsare atmosphere asaresultofhumanactivitiesismuchfasterthantherateatwhichit polar bearsandotheranimals thatlivethere. dioxide levelshavealsoledto shrinkingofthepolaricecaps,destroyinghabitat for it difficultforthesespeciesto continuelivingintheirnaturalrange.Increasedcarbon already beenobservedmovingintonewareas,because the changesinclimatemake temperatures, whichcanhaveadevastatingeffectonecosystems. Somespecieshave the amountofcarbondioxideinatmospherehasbeen linkedtoincreasingglobal energy forplantgrowth,butkeepinfraredradiation,orheat, fromescaping.Increasing as agreenhouseforgrowingplants.Theyallowsunlight to passthroughandprovide Carbon dioxideisoneofseveralgreenhousegases.These gasesactinasimilarway lowers thepHofwater.Whateffectsdoyouthinkthismighthaveonmarinelife? ocean throughdiffusion.Carbondioxidereactswithwatertoproducecarbonicacid,which substantial increaseinatmosphericCO Carbon dioxideemissionsreleasedfromtheburningoffossilfuelshaveledtoa Climate Change INFER Atmospheric CO FIGURE 10:

Source: Source: As carbon dioxide is added to the atmosphere, more carbon dioxide also enters the As carbondioxideisaddedtotheatmosphere,morealsoenters Parts per million 300 320 340 360 380 400 Atmospheric carbondioxidelevelshaverisensubstantiallysince1960. Scripps Institution of Oceanography at UC San Diego, NOAA Earth System Research Laboratory Research System Earth NOAA Diego, San UC at Oceanography of Institution Scripps 1960 2 atMaunaLoa Observatory Atmospheric CO 1970

1980 2 . Therateatwhichcarbondioxideentersthe 2 atMaunaLoaObservatory Year 1990 average value seasonal fluctuations 2000 2010

© Houghton Mifflin Harcourt Publishing Company • Image Credits: (t) ©Aerial Archives/Alamy (b) ©Karen T. Borchers/San Jose Mercury News/MCT/NewsCom land, it carries some of the soil with it. land, itcarriessomeofthesoilwithit. removes plantsthatholdthesoilinplace.Whenwaterrunsoff increase therateofsoilerosion.Plowingloosensand Eroded soilwashesintonearbywaterways.Mostfarmingmethods Erosion isthemovementofrock,soil,andsandbywindwater. water bodies,impactingthequality. bloom. Similarly,pesticidescanbetransportedbyrainintonearby stimulate growthofaquaticproducerssuchasalgae,calledanalgae of thesechemicalsaltersthenutrientbalanceinwaterandcan and phosphorustorunoffintonearbywaterbodies.Theaddition growth. Whencropsareoverfertilized,raincausesexcessnitrogen decades. Fertilizersareusedtoenrichthesoilandstimulateplant and phosphatemininghasincreasedgreatlyoverthelastfew The productionoffertilizersthroughindustrialnitrogenfixation Agricultural Runoff mining runoff. can impactecosystems. Excess amountsofnutrients,suchasphosphorus,andsoilerosion erode therockandtransportnutrientstonearbywaterways. removed. Thisexposestherocktoairandwater.Waterwind To obtainmineralsfromthisrock,soilandvegetationare thick layersofsoilwithinecosystemssuchasforestsorgrasslands. Rock formationsintheenvironmentareoftenburiedbeneath Mining Runoff EXPLAIN EXPLAIN Fish-eating birdsandotheranimalsareimpactedbecausetheyrelyonthefishforfood. deplete theoxygen|nitrogencarbonthatfishandotherorganismsneedtosurvive. ecosystems, algaeblooms,andthebacteriathatbreakdowndeadalgae,can Agricultural runoffcanaffecttheoverallhealthofanecosystem.Incaseaquatic ecosystems. Runoffthatcarriesexcessnutrientscancause algaeblooms.Theeffectsof Both rockandbodiesofwaterareconsideredatype Evidence Notebook could beaffecting yourlocalecosystem.Whatcanyou dotodecreaseyourimpact? day thatmayimpactoneofthesecycles. Explainhowyouareinteractingwith the cycleandhow that other cyclesofmatterwillcauselasting damagetoEarth.Makealistoftheactivities youperformina

Use thecorrecttermtocompletestatementaboutagriculturalrunoff. Use thecorrecttermstocompletestatementabout water soil erosion Many scientistsworrythattheinfluence humanshaveonhydrologicand alsoincreasewaterpollutionandcanclogwaterways. canreadilytransportnutrientsfromrocktoaquatic incyclesofmatter.Whenrockisexposedformining, reservoir

Lesson 2 Cycling of MatterinEarth’s Spheres aquatic ecosystems. FIGURE 12: nutrients togroundwater andwaterways. FIGURE 11: Mining runoff negativelyaffects Agricultural runoff introduces 173 DO NOT EDIT--Changes must be made through “File info” CorrectionKey=CA-B

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Careers in Science

Oceanographer

The ocean is a large system with many different Among the sites that Aburto-Oropeza studies is Cabo components. Matter, such as minerals and gases are Pulmo Marine National Park, located in the Gulf of dissolved in the water. A vast array of organisms live California. Prior to its establishment in 1995, the region in this huge aquatic ecosystem, from single-celled had been severely overfished. The protected region plankton to Earth’s largest animal, the blue whale. The now has a strict “no-take” policy that prohibits fishing. ocean also contains energy absorbed from the sun and In a recent assessment of the reserve, Aburto-Oropeza energy from Earth’s interior. and his colleagues found that between 1999 and Oceanography is the study of the ocean system. Because 2009, the reserve’s biomass showed an increase of the ocean system is so huge, oceanographers must 465%, which translates to a ton of new fish produced study many different parts of the system. For example, each year. The results of their study indicate that, with to answer questions about scalding hot thermal vents proper management, fish communities can recover on the deep ocean floor, different oceanographers to a level comparable to areas that have never been work together to observe, collect, and examine vent fished before. organisms, measure the temperature and pressure of the seawater, and analyze the chemistry of water and ASK List questions that you have about how changes rock on the seafloor. to coral reefs could affect human society. Octavio Aburto-Oropeza is an associate professor of marine biology at the Scripps Institution of Oceanography at UC–San Diego. His research focuses on marine reserves and commercially-exploited marine species and their fisheries.

FIGURE 13: Oceanographer Octavio Aburto-Oropeza dives near the San Benito Islands off Baja California. © Houghton Mifflin Harcourt Publishing Company • Image Credits: ©Claudio Contreras Koob

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© Houghton Mifflin Harcourt Publishing Company For example,howwouldyoumodeltherelationshipbetweenhumansandcoralreefs? answering yourquestion?Explaintheroleofeachtypeoceanographer. reefs withapartner.Togetherdecideononequestionthatyouwanttofocuson. question abouttherelationshipbetweenhumansandcoral reefs. oceanographers studythecomponentsofseawater eruptions andearthquakesontheseafloor.Chemical sediments, landforms,andprocessessuchasvolcanic ecosystems. Geologicaloceanographersstudytherock, Biological oceanographersstudymarineorganismsand components andprocessesintheoceansystem. Different typesofoceanographersstudydifferent biology, geology,chemistry,andoceanography. work ofmanyscientistsindifferentfields,suchas Understanding naturalsystemsoftenrequiresthe

MODEL PLAN PREDICT COLLABORATE HUMAN EFFECTS ON

EARTH’S SYSTEMS With yourpartner,writeastatementthatsummarizesplan toaddressyour

With yourpartner,discusshowtomodelasystemthatrelatesquestion. you willusetoaddressyourquestion. Also,focusonthehumanconnectionstoquestion. answer yourquestion.Includespecific stepsforconductingtheresearchandcitesources Language ArtsConnection

What typeortypesofoceanographerwouldbemostlikelyinvolvedin

Share yourquestionsabouttheinteractionsbetweenhumansandcoral

MODELINGA CHEMICAL CYCLE Workwithyourpartnertodeveloparesearchplan

of oceanographers? towards researchcouldbemadebythedifferenttypes work ofdifferenttypesscientists?Whatcontributions reef community,whyisitimportanttoconsiderthe If youaretryingtoanswerquestionsrelatedacoral and gravity. moves andinteractswithoutsideforcessuchaswind temperature andpressurewaysthatoceanwater Physical oceanographersstudycharacteristicssuchas and thechemicalreactionsthatoccurinseawater. LUNGS OF THE Lesson 2 PLANET Cycling of MatterinEarth’s Spheres of theseotherpaths. Go onlinetochooseone 175 DO NOT EDIT--Changes must be made through “File info” CorrectionKey=CA-B

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Lesson Self-Check

CAN YOU EXPLAINSOLVE IT? IT?

FIGURE 14: The Biosphere 2 project taught scientists many lessons about the cycling of matter and energy.

Not long after the Biosphere 2 experiment began, carbon dioxide levels rose to dangerous levels. Biospherians were so starved for oxygen, they panted as they climbed stairs. Analysis of the Biosphere 2 systems showed that huge amounts of compost had been added to soils at the beginning of the experiment. This allowed soil bacteria to multiply at stunning rates, pumping out vast amounts of carbon dioxide and tilting the balance in the Biosphere 2 atmosphere. To restore the balance, oxygen eventually had to be pumped into the facility.

Evidence Notebook Refer to your notes in your Evidence Notebook to explain why scientists had problems with low oxygen levels and increasing carbon dioxide levels in Biosphere 2. Use the following questions to develop your explanation: 1. How do matter and energy cycle through Earth’s spheres? Use a model to illustrate the cycling of matter and the flow of energy within and between Earth’s spheres. 2. Why do you think researchers had problems with low oxygen in Biosphere 2? Use a model that includes trophic levels in your explanation. 3. How would you solve this problem with Biosphere 2? How would your solution work on a global scale? © Houghton Mifflin Harcourt Publishing Company • Image Credits: ©James Marshall/Corbis

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Name Date CHECKPOINTS

Check Your Understanding 3. Which statement describes a difference between the nitrogen and carbon cycles? 1. Place these events in the correct order to show the cause-and-effect relationships that lead a. The carbon cycle involves only plants. to algae blooms. b. The nitrogen cycle requires a process called nitrogen fixation that is carried out by a. decomposers that break down dead certain bacteria. algae take in oxygen for cellular c. The carbon cycle requires freezing respiration temperatures. b. lack of oxygen causes fish and other d. The nitrogen cycle occurs entirely in aquatic organisms to die the ocean.

c. excess nutrients from fertilizer are 4. Which of the following are common to all of the chemical cycles? Select all correct answers. transported by rain to nearby bodies of water a. reservoirs and processes b. an atmospheric component d. people overfertilize crops and lawns c. photosynthesis and respiration e. algae overgrow, become overcrowded, d. living things as a reservoir and die e. the sun as a source of energy f. can be affected by human activities f. excess nitrogen and phosphorus leads

to overgrowth of algae 6. 5. Recently, some areas in the United States have seen an increase in trees due to reforestation efforts. How 2. Place these steps in the correct order to explain might the carbon cycle be altered after a large-scale how carbon moves between the atmosphere and reforestation effort? Select all correct answers. the biosphere in the carbon cycle. a. Atmospheric carbon dioxide levels would a. Organisms carry out cellular respiration, decrease because the new trees would absorb carbon dioxide during photosynthesis. which converts glucose and oxygen to carbon dioxide and water. b. Atmospheric carbon dioxide levels would stay the same because the new trees would absorb b. Plants use water and carbon dioxide as much carbon dioxide as they produce. from the atmosphere to make glucose c. Atmospheric carbon dioxide levels would and oxygen through photosynthesis. decrease as trees grew larger and more carbon was stored in wood. c. Some animals eat plants and store d. Atmospheric carbon dioxide levels would chemical energy from the plants in increase as new trees allowed ecosystems to their bodies. support an equal number of new animals.

d. Carbon dioxide is released by organisms 6. The following are processes in the water cycle. and moves into the atmosphere. Which of these processes are driven by energy from the sun? Select all correct answers. © Houghton Mifflin Harcourt Publishing Company a. runoff b. evaporation c. percolation d. melting e. transpiration

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CHECKPOINTS (continued)

7. There is evidence that the increasing carbon dioxide levels in the atmosphere are causing oceans to become more acidic. Ocean acidification may negatively impact species of phytoplankton, which are microscopic photosynthetic organisms that live in surface waters. Explain how the carbon cycle might be affected if phytoplankton populations were to decrease.

8. Decomposers are an important part of many chemical cycles. Some carry out aerobic respiration, and some use anaerobic respiration as they break down organic matter. Explain why decomposers are so crucial for the cycling of matter in ecosystems.

MAKE YOUR OWN STUDY GUIDE

In your Evidence Notebook, design a study guide that supports the main ideas from this lesson: Cycles of matter are processes that move matter through and among Earth’s spheres. These cycles can be impacted by human activity. Modeling changes to the carbon cycle allows us to predict future impacts on ecosystems. Remember to include the following information in your study guide: • Use examples that model main ideas. © Houghton Mifflin Harcourt Publishing Company • Record explanations for the phenomena you investigated. • Use evidence to support your explanations. Your support can include drawings, data, graphs, laboratory conclusions, and other evidence recorded throughout the lesson. Consider how energy allows matter in the closed Earth system to cycle between Earth’s spheres.

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