Solutions for Principles Of Environmental Science 8th Us Edition by Cunningham by 6alsm

TeachersGuide

Notesoneachlabandsampleanswersforthelabsquestionsarelistedbelow.Studentsandteachers maygeneratemorepossibleanswersthatarecorrectaswell.Thelabscanbedoneinanyorderorin theorderthatworksbestfortheseasonduringwhichthelabistaught.Forexample,Iliketorunthe StreamLabwhenitiswarmer.Inthenortherntemperatezonethismeanstheendofthespringtermor thebeginningofthefallterm.Similarly,theforestecologylabsareprobablyeasiesttorunwhenthe leavesareonthetreesforidentificationpurposes.

Thelabsapproachtheworldfromanecologicalperspectiveandasacollectionattempttoteachthe studentaboutmanyaspectsoftheenvironment,includingsoilhealth,streamhealth,foresthealth, cleanair,aswellasagriculturalanddevelopmentissues.

Asetoffourorfivequestionsfollowseachlab.Sometimesthesequestionsareaskedprogressively throughoutthelab,asinthewormfarminglab.Mostcanbedoneattheendofclassandturnedinthat dayorforhomeworkandturnedinthefollowingweek.

Theteacherisalsofreetoaskstudentstocompleteascientificpaperbasedonanyofthelabs.Allof thelabsexceptfortheSewageTreatmentPlantandOrganicFarmfieldtripsareexperimentalin natureandascientificpapercouldeasilyworkforthis.

1.StreamEcology

Thislabcanbedoneatalocalstreameitheronornearcampus.Theprotocolispartoftheprotocol usedintheAdopt-A-Streamprogram,andlongtermdatacouldbegatheredandthestreamadoptedby theclassifitwillberepeated.

Questions

1.Thewaterqualityratingwilldependontheoverallhealthofthestreamandalsotheseasonin whichsamplingwasconducted.

Havinganunderstandingoftheupstreamlanduses(residential,agricultural,etc)willbehelpful forunderstandingtheresults.

2.Macroinvertratesarelikelyfoundinleafpacksandunderrocksbecausetheyhavemoreshelter there.Leafpacksprovidebothfoodandshelter.

3.Ifastreamhasahealthyriparianzoneitmaybequitehealthydespiteagreatdealoffertilizer useinthewatershedupstream.Farmsaremorelikelytohavesomenegativeeffects downstreamifanimalsareabletoaccessthestream.

4.Resultsmayvarybasedonseasonduetodifferenttemperaturesanddegreesoflanduse.Late spring/earlysummerislikelytoyieldbetterresultsbecausethelowertemperatures,compared tolatesummerearlyfallresultinhigheravailableoxygenformacroinvertebrates.Also,people arelesslikelytohavestartedfertilizingtheirlawnsbylatespringtothesamedegreetheywill haveinearlyfall.

Agoodhypothesismightincorporatethefactorsdiscussedabovesuchastheseasoninwhich samplingoccurred,upstreamlandusesinthewatershed,anddegreeofriparianvegetationpresent.

2.MeasuringDiversity

Thislabismeanttobeveryflexibleandcanbeconductedintheecosystemofchoiceofthe teacher.Forexample,asamplingoftheleaflitterinaforestcouldbedone,astandoftreesorevenan aquaticecosystem.

Calculationscanbedoneinclassifstudentsbringacalculator,athome,orinthelabonanExcel

Questions

1.Theanswertoquestiononewilldependonthedatagatheredinclass.

2.Theanswertoquestiontwowilldependonthedatagatheredinclass.

3.SimpsonsIndexofDiversitydoestakeintoaccountbothrichnessandevennessbecauseone needstoknowtherichness,ornumberoforganisms,tocalculatetheevenness,measuredby relativeabundance.TherelativeabundancemeasureisusedtocalculatetheIndexofDiversity.

4.Studentsmayanswerthatthehighestdiversityintheworldisfoundintherainforestorincoral reefssuchastheGreatBarrierReef.Botharetrueinaway.Forrainforestshighdiversityis attributedtothegreatdealofsunlightandrainthatthesetypesofforestsreceive,coupledwith thetensofthousandsofyears,orlonger,thattheseecosystemshavebeenevolving.

Chapter1

1.Globalpopulationsarerising,butinthefuturetheyshouldstabilize,althoughatwhat levelandwhendependsonfertilitychanges.Fertilityratesarefallingeverywhere,and theglobalaveragehasdeclinedfrom5tolessthan2.5childrenperwoman.

2.Ecologicalservicesincludemanyfactorsandresourceswerelyon.Oftentheyre describedintermsofprovisioning,regulating,supporting,andculturalservices.Climate regulation,waterfiltration,andfoodprovisionareafewexamples.

3.Ahypothesisisatestable,provisionalexplanation.Ascientifictheoryisanexplanation supportedbyalargebodyofempiricalevidenceandregardedbyamajorityofscientists aslikelytobecorrect.

4.Thescientificmethodinvolves1)identifyingaquestion,2)formingatestablehypothesis, 3)collectingdata,4)interpretingresults,5)reportingresultsforpeerreview, 6)publishingfindings.Seefigure1.4.

5.Probabilityisameasureofhowlikelysomethingistooccur.Anexampleisflippinga coin.Eachtosshasa50%probabilityoflandingonaparticularside.

6.Scientiststrytoreservejudgmentbecausetheyknowthatbetterevidencecouldemerge fromfuturetestsorevidences.Thustheytrytobeskepticalofevidenceandtolookfor solid,unbiasedevidence.Thisisalsowhytestsrequirereplication:onetestresultcould beanaccidentoranoutlier.Manytestsarebetterthanafew.

7.Thefirststepincriticalthinkingistoask,Whatisthepurposeofmythinking?

8.Utilitarianconservationispragmatic,efficientresourceuseforthegreatestgoodforthe greatestnumberforthelongesttime.GiffordPinchotandTeddyRooseveltwereleaders inthismovement.Biocentricpreservationemphasizestherightofotherorganismsand natureasawholetoexistregardlessoftheirusefulnesstous.JohnMuirwasaleading proponentofthisphilosophy.

9.Waterisacriticalresourcebecause1.1billionpeoplelackaccesstocleanwater,15 millionpeopledieannuallyfromdiseaseslinkedtopollutedwaterorinadequate sanitation,andby2025,theU.N.warns,three-quartersofallhumansmayliveinwaterstressedcountries.

10.Infigure1.5,themostdramaticwarmingoccursathighlatitudes,especiallynorthern Canada,Siberia,andpartsoftheArcticOcean.

11.Theratioofpercapitaincomeisabout52:35(oralittlelessthan5:3)forNorthAmerica: EastAsia.ForNorthAmerica:SouthAsia,theratioisabout52:2(orabout25:1).

12.Thepoorestpeopleareoftenboththevictimsandagentsofenvironmentaldegradation. Forcedtomeetshort-termsurvivalneedsatthecostoflong-termsustainability,they suffermostfromenvironmentaldamagebecausetheyhavefewotheroptions.

13.Sustainabilityisasearchforecologicalstabilityandhumanprogressthatcanlastoverthe longterm.Sustainabledevelopmentisdefinedasmeetingtheneedsofthepresent withoutcompromisingtheabilityoffuturegenerationstomeettheirownneeds.

Chapter2

1.Twoprimarynutrientsthatcauseeutrophicationarenitrogen(N),andphosphorus(P).

2.Systemsarenetworksofinteractionsamonginterdependentunitsorcompartmentsas wellasprocessesorflowsthatlinkthosecomponents.Apositivefeedbackloopenhances oracceleratesaprocessandastatevariable.Anegativefeedbackinhibitsorreversesa processorreducesastatevariable

3.Carbonatoms,likeallmatter,areconstantlycycledinlivingorganisms.Giventhehuge numberofcarbonatomsinyourbody,itsalmostcertainthatsomeofthemwerealso partofsomeprehistoricorganisms.

4.Watermoleculesarepolar,whichmakeswaterasuperbsolvent.Wateristheonly inorganicliquidthatexistsatnormalambienttemperatures.Thisprovidesaliquid mediumforlifeprocesses.Watermoleculesarehighlycohesive.Thisresultsincapillary action.Waterexpandswhenitcrystallizessothaticefloats.Waterhasahighheatof vaporization,sowecanremovealargeamountofheatthroughevaporation.Waterhasa highspecificheat,makingitanidealmediumforstoringheatandmoderatingtheearths temperature.

5.DNA(deoxyribonucleicacid)isanextremelycomplex,doublehelix-shapedmolecule thatcontainsthegeneticmaterialthatdefinesanorganismstraits.DNAexistsinthe nucleusofcells(forallcell-basedorganisms).Itismadeupofnucleotideslinked togetherinlongchains.ThespecificsequenceofnucleotidesinaDNAmoleculecarries thegeneticinformationthatcodesforproteinstructureandgiveseachorganismits uniqueinheritablecharacteristics.

6.Heatisstoredenergy,butifitisstoredinadiffuseform,itisusuallyhardtoconvert fromoneformtoanother.Weusethetermlow-qualityenergytorefertodiffused, dispersed,lowtemperatureenergythatisdifficulttogatheroruseforproductivework. High-qualityenergy,incontrast,isintense,concentrated,high-temperature,anduseful forwork.

7.Materialscycleendlesslyinthebiosphere,orbetweenbiosphere,geosphere, hydrosphere,andatmosphere,becauseofthelawofconservationofmatter.Energy followsalinearpathbecauseitcontinuallydegradestolower-qualityformsasitisreused,andultimatelyenergydissipatestospaceasheat.Thisisthesecondlawof thermodynamicsineveryenergyexchange,someoftheenergyisconvertedfrom higherqualitytolowerquality.Thus,tokeeplivingprocessesgoing,therehastobea constantenergyinputandasinktowhichsurpluswasteenergy(suchasheat)can dissipate.

8.Oureyesaresensitiveonlytovisiblelight(0.4to0.7um),whichhappenstobethemost commonwavelengthsinsolarradiation.Shortultravioletwavelengths(microwaves(10 nmor10x10-9m)are1million(1x106)timesshorterthanmicrowaves(1mmor1x 10-3m).

9.Extremophilesliveinextremeconditionsatthebottomoftheocean,inhotsprings,or deepintheearthscrust.Theygettheenergytheyneedtolivebychemosynthesis: reactionsthatusechemicals,suchashydrogensulfideorhydrogengasasanenergy source.

10.Formostorganismsontheearthssurface,theultimatesourceofenergyisthesun,and thesinkforwasteenergyisouterspace.

11.Greenplantscapturesolarenergythroughphotosynthesis,aseriesofchemicalreactions thatoccurinchloroplasts.Theenergycapturedinthisprocessisusedtocreatechemical bondsinorganicmolecules.Thesemoleculesservebothasanenergysourceandbuilding materialforallplantsandanimals.

12.Aspeciesismadeofalltheorganismsofthesamekindthatareabletobreedunder naturalconditionsandproducelive,fertileoffspring.Apopulationconsistsofallthe membersofaspecieslivinginagivenareaatthesametime.Abiologicalcommunityis madeupofallthepopulationsofdifferentspecieslivingandinteractinginagivenareaat aspecifictime.

13.Big,fierceanimals(suchasgrizzlybears,tigers,andgreatwhitesharks)areusuallythe topcarnivoresintheirecosystem.Theyneedtobelargeandfiercetocatchtheirprey. Becausetheyareatthetopoftheecologicalpyramid,ittakesmanyorganismsatlower trophiclevels(andtherefore,largehomeranges)tosupportthesebigcarnivores.Thus, thereareneververymanyoftheminagivenarea.Theiradaptationsastoppredators makethemdangeroustohumans.Theyalsooftencompetewithusforfood,sowetendto eliminatethemeitherdirectlybyhunting,orindirectlybyreducingtheirfoodsuppliesor eliminatingtheirhabitat.

14.Anexampleofaninvertedecologicalnumberspyramidmightbeasinglelargetree supportingmanyherbivorousinsects,orasinglecoyotesupportingmanyparasites.

15.Humansreleaseabout7GTofcarbonannuallycomparedto100GTreleasedby respirationfromland-basedplants,animals,andmicrobes.

Chapter3

1.Tolerancelimitsrestrictthedistributionandabundanceofspeciesbyforcingthemtolive inaspecificenvironment.Saguarocactuscannotwithstandextendedfreezing temperatures,sotheirdistributionisstrictlylimitedbyelevationsatwhichfreezingnights occurregularly.Similarly,youngdesertpupfishonlyliveinhotwater(20-36°C),forcing themtoremainnearhotspringsinthedesert.Bycontrast,atallagesthecommoncarp andEuropeanstarlingsurviveinabroadrangeoftemperatures,andthroughhuman introductionnowoccupyeverycontinentintheworldexceptAntarctica.

2.Allopatricspeciationistheevolutionofseparatespeciesindifferentlocations.This occurswhenanancestorpopulationhasbeenseparated.Sympatricspeciationisthe evolutionofseparatespeciesinthesamelocation.Thismightoccurwhensubsetsofa populationcometooccupydifferentnichesorusedifferentresources.

3.Selectivepressureisthecaseinwhichcertaintraits,suchasaheavybeakinaplacewith thick-coatedseeds,allowsomeindividualssomewhatgreaterreproductivesuccessthan otherindividuals.Eventuallythosetraitsbecomecommoninthepopulation,whileother traitsbecomerare.Selectivepressuresinyourlocalitycouldincludetemperature,water, wind,predation,food,fire,oranumberofotherenvironmentalfactors.

4.IntheTypeIcurve,mostindividualssurvivetoarelativelymatureage,thendieatanold age.TypeIIdescribesapopulationthatisequallylikelytodieatanyage.TypeIII representsapopulationinwhichmostindividualsdieveryyoung,butasmallproportion ofindividualssurvivetoreachmaturity.

5.Symbioticrelationshipsinvolvetwospecieslivingtogether.Mutualismreferstoa relationshipinwhichbothspeciesbenefit,asinthecaseofalgaeoroxpickersonan

12LABORATORYANDFIELD

EXERCISESIN

ENVIRONMENTALSTUDIES

byJessicaSeares,Ph.D.

1.StreamEcology:BiodiversitySampling

Goal:Tomeasurealocalstream’shealthbylookingformacroinvertebrates

Background:Thedominantanimallifeinsmall-orderstreamssuchastheoneyouwillbeworkinginaremacroinvertebrates,whichincludeinsectlarvaethatwillmatureandleavethestreamasadults(includingcaddisflies, springtailsandmayflies).

Macroinvertebratesdonothaveaspinalcord,arebigenoughtoseewiththenakedeye,andareimportant ecosystemplayersinsmall-orderstreams.Ingeneral,theyaremorelikelytobefoundinleafpacksandunderrocks intherifflesofstreamsratherthanpools.

Becausewatermovessorapidlyinstreams,itcanbedifficulttomonitorpollutioninthem.However,certainkindsof pollutioncanhavelong-termeffectsonthelivingorganismsinstreams.Wewillsamplethestreamfororganismsand givetheorganismsthatareleasttolerantofpollutionagreaterweightinourbiologicalanalysisthanorganismsthat areverytolerantofpollution.Theorganismsfoundwillthusbeamarkerforthepastpresenceofpollution–the presenceofsensitiveorganismsindicatesahealthystream.

HowDevelopmentinaWatershedAffectsStreams: Awatershedisanareaoflandthatdrainsintoacreekorriver.Impervioussurfacessuchasroadsandrooftops acceleraterunofffromrain,increasingtherateofsoilerosionintolocalcreeks.Thephysicaleffectsoferosionon streamsincludesteepeningofbanks,andincreasedsedimentationloadinstreams,resultinginareducednumberof breedingsitesforstreamwildlife,bothmacroandmicro.

Fertilizers,farms,andleakingseptictanksorsewerlinesnegativelyaffectstreamorganisms.Streamsarenaturally oligotrophic(nutrient-poor)andincreasedlevelsofnutrientsintheformoffertilizerorhumanwastemaycausealgal blooms,whichinturnreduceoxygenlevels,threateningfishandmacroinvertebrates.

Deforestationforyards,constructionsites,andfarmscanreducetheabilityofstreamsidevegetationtobufferexcess nutrientsandsedimentsfromenteringstreams.Streamsidevegetationiscalledariparianbufferbecauseofthe importantecologicalroleitplaysinslowingdownrunoff,sediment,andprocessingnutrientsbeforetheyenter streams.Manystatelawsrequireda25footriparianzoneforsmall-orderstreams,butexemptionsarefrequently madeforagricultural,lawnandgardenuse.Removingstreamsidevegetationcanincreasesedimentload,erosion, fertilizersandotherpollutantsinstreams.Forthisreasonitisimportanttoalwaysmaintainabuffer,inyourownor parent’sbackyard,ifitbordersacreek.Thismeansnotmowingtotheedgeofthewater.Thiswillalsoreducethe threatoffloodingdownstreamduringstorms.

Materials:Rubberboots,D-netsforstreamsampling,plastictubs,Petridishes,forceps,magnifyinglenses,stream macroinvertebratekeys

Method:Ingroupsofatleasttwo,findariffleforsampling.:HaveonepersonstanddownstreamholdingtheD-net sothatitsmouthfacesupstreamandthenettouchesthefloorofthestreambed.Anotherpersonstandingtwotofour feetupstreamshouldkickatthestreambedforafewsecondstodislodgetheleaflitter.Thisshouldcause organismstodriftintoyournet.Afteracoupleofminutes,climbontothebankandgentlyemptyyournetintoa plastictubthathasabitofwaterinit(addmoreifnecessary).Whenyouemptyyournetsintoyourtraysyour organismsitmaytakeawhileforyourorganismstostartmoving.Whentheydo,usethekeytodeterminewhich speciesyouhave,andkeepatallyontheattachedsheet.Whenyouaredonegentlyreturnthewaterandorganisms justupstreamoftherifflewhereyousampled.

IdentifyingWhatYou’veFound:

Usetheguidebelowtohelpyoufillinthedatatableattheendofthelab.Clickonthelinkednameoftheorganism foradescription.Alsopleasenote,theorganismsyoufindmightnotmatchthoselistedbelowexactly.Tryto categorizetheanimalsyoufindascloselyaspossibletothesketches.Usingfieldlenseswillhelpyoutosee defininingfeaturesliketails,legs,andsegmentationmoreclearly.

MacroinvertebratesThatAreSensitivetoPollution MacroinvertebrateguideusedwithpermissionfromRickWebbandtheShenandoahWatershedStudy

FoundinGoodQualityWater

Stonefly RiffleBeetleAdult

GilledSnail Planarian

Mayfly–notethreetails WaterPenny

Caddisfly

Hellgramite

MacroinvertebratesThatAreSomewhatSensitivetoPollution

FoundinGoodorFairQualityWater

Crayfish

Alderfly

CraneFly

RiffleBeetleLarva

Damselfly

Sowbug

Dragonfly

WatersnipeFly

Scud WhirligigBeetleLarva

Fishfly

ClamorMussel

Cunningham8eCRITICALTHINKINGANSWERS

Chapter1

1.Asgirlsgainaneducation,theyhavemoreincomevaluefortheirfamilybeyondchild production,sotheremaybelesspressuretomarryyoungandhavemanychildren;they mayalsogainmoreabilitytoarguefortheirownemploymentpriorities..

2.Therearemanyexistentialquestions,suchas,whatisthemeaningoflife?Istherelife afterdeath?orDowehavearighttokillothers?Thatsciencecan’tanswer.Manyof thesearequestionsevaluatedwithempiricalevidence,butratherhavetodowithvalues andlifeexperience.

3.Youcanmaintainobjectivityinseveralways.Keepingtheidentityofsurveyrespondents secretfromthosewhoevaluateresponseshelpstomaintainimpartialityandobjectivity. Youcandoblindorevendouble-blindexperiments.Youcancarefullyfollowtheordered stepsofthescientificmethodinordertobesureyouareproperlytestingyouhypothesis

4.Whethertherearethereenoughresourcesdependsonourchoicesinpatternsof production,consumption,andcooperation.Italsodependsonwhatyouconsidera decent,secure,happylife.AsPaulEhrlichpointsout,thecarryingcapacityforsaints mighteasilybe10billion,butthenumberofselfish,wasteful,greedy,destructive individualstheworldcantolerateisfarlower.Whetheryouthinkwehaveenough resourcesdependsalsoonwhatkindofresourceconsumptionweconsidernecessary. Whatlevelofresourceconsumptiondoyoureallyneedtobehappyandhealthy?Does yourhappinessdependonthesizeofyourmaterialgoodsoronthequalityofyour friendships?

5.Instudyingtheenvironmentalimpactsofarichversuspoorcountry,yououghtto examinenotonlythelocalenvironmentofeachcountry,butalsoevaluatetheimpactsof extracting,shipping,andusingresourcesfromremotelocations.Inotherwords,whatare theenvironmentalimpactsofwealthylifestylesandpolitical/economicsystemsonthe countriesthatproducethegoodsandservicestheyuse?

Chapter2

1.Theboundariesofanecosystemareoftendefinedintermsofthegeneralcharacteristics oftheplantsandanimalsthatliveinanareaforexampletheboundariesofadesert ecosystemmightbewheremoistureincreasesandvegetationbecomesmoreabundant. Allecosystemsareopenwithregardtoenergysource(usuallythesun),butconsiderthe sourcesofwater,air,food,buildingmaterial,andotherresources.Wheredotheycome from?

2.Entropymeansdisorderordisorganizationorreducedstructure.Entropyineverydaylife includesdeath,decay,rustingmetal,andwaterrunningdownhill,orevendisarrayin yourroomthedayafteryouhavecleanedit.Doestheprincipalofentropyexplainwhy it’simpossibletobuildaperpetualmotionmachine?Constantenergyisneededto maintainorderandcleanliness,inmostcases.

3.Ifallchemicalbondswereextremelystrong,yourcellswouldnotbeabletobreakthem apartinordertoreleaseenergyorformnewcompounds.Substanceswithstrongbonds aresolid,notmoveableandfluid.Ifallchemicalbondswereextremelyweek,no structurescouldexist,andyourcellscouldnotformstablestructuresorcompoundsto