EnvirOnmEnTal SciEncE · visit backyard bird feeders. Because many people over the centuries have...
Transcript of EnvirOnmEnTal SciEncE · visit backyard bird feeders. Because many people over the centuries have...
EnvirOnmEnTal SciEncE
How to Use This PamphletThe secret to successfully earning a merit badge is for you to use both the pamphlet and the suggestions of your counselor.
Your counselor can be as important to you as a coach is to an athlete. Use all of the resources your counselor can make available to you. This may be the best chance you will have to learn about this particular subject. Make it count.
If you or your counselor feels that any information in this pamphlet is incorrect, please let us know. Please state your source of information.
Merit badge pamphlets are reprinted annually and requirements updated regularly. Your suggestions for improvement are welcome.
Send comments along with a brief statement about yourself to Youth Development, S209 • Boy Scouts of America • 1325 West Walnut Hill Lane • P.O. Box 152079 • Irving, TX 75015-2079.
Who Pays for This Pamphlet?This merit badge pamphlet is one in a series of more than 100 covering all kinds of hobby and career subjects. It is made available for you to buy as a service of the national and local councils, Boy Scouts of America. The costs of the development, writing, and editing of the merit badge pamphlets are paid for by the Boy Scouts of America in order to bring you the best book at a reasonable price.
ENVIRONMENTAL SCIENCE
BOY SCOUTS OF AMERICAMERIT BADGE SERIES
Requirements1. Makeatimelineofthehistoryofenvironmentalsciencein
America.IdentifythecontributionmadebytheBoyScoutsofAmericatoenvironmentalscience.Includedates,namesofpeopleororganizations,andimportantevents.
2. Definethefollowingterms:population,community,eco-system,biosphere,symbiosis,niche,habitat,conservation,threatenedspecies,endangeredspecies,extinction,pollutionprevention,brownfield,ozone,watershed,airshed,nonpointsource,hybridvehicle,fuelcell.
3. DoONEactivityfromEACHofthefollowingcategories(usingtheactivitiesinthispamphletasthebasisforplanningandprojects):
A. Ecology
(1) Conductanexperimenttofindouthowlivingthingsrespondtochangesintheirenvironments.Discussyourobservationswithyourcounselor.
(2) Conductanexperimentillustratingthegreenhouseeffect.Keepajournalofyourdataandobservations.Discussyourconclusionswithyourcounselor.
(3) Discusswhatisanecosystem.Tellhowitismain-tainedinnatureandhowitsurvives.
B. AirPollution
(1) Performanexperimenttotestforparticulatesthatcontributetoairpollution.Discussyourfindingswithyourcounselor.
35892 ISBN 978-0-8395-3363-4©2006 Boy Scouts of America2010 Printing
BANG/Brainerd, MN4-2010/059741
EnvironmEntal SciEncE 3
(2) Recordthetripstaken,mileage,andfuelconsumptionofafamilycarforsevendays,andcalculatehowmanymilespergallonthecargets.Determinewhetheranytripscouldhavebeencombined(“chained”)ratherthantakenoutandback.Usingtheideaoftripchaining,determinehowmanymilesandgallonsofgascouldhavebeensavedinthosesevendays.
(3) Explainwhatisacidrain.Inyourexplanation,tellhowitaffectsplantsandtheenvironmentandthestepssocietycantaketohelpreduceitseffects.
C. WaterPollution
(1) Conductanexperimenttoshowhowlivingthingsreacttothermalpollution.Discussyourobservationswithyourcounselor.
(2) Conductanexperimenttoidentifythemethodsthatcouldbeusedtomediate(reduce)theeffectsofanoilspillonwaterfowl.Discussyourresultswithyourcounselor.
(3) Describetheimpactofawaterbornepollutantonanaquaticcommunity.Writea100-wordreportonhowthatpollutantaffectedaquaticlife,whattheeffectwas,andwhethertheeffectislinkedtobiomagnification.
D. LandPollution
(1) Conductanexperimenttoillustratesoilerosionbywater.Takephotographsormakeadrawingofthesoilbeforeandafteryourexperiment,andmakeapostershowingyourresults.Presentyourpostertoyourcounselor.
(2) Performanexperimenttodeterminetheeffectofanoilspillonland.Discussyourconclusionswithyourcounselor.
(3) Photographanareaaffectedbyerosion.Shareyourphotographswithyourcounseloranddiscusswhytheareahaserodedandwhatmightbedonetohelpalleviatetheerosion.
E. EndangeredSpecies
(1) Doresearchononeendangeredspeciesfoundinyourstate.Findoutwhatitsnaturalhabitatis,whyitisendangered,whatisbeingdonetopreserveit,andhowmanyindividualorganismsareleftinthewild.Preparea100-wordreportabouttheorganism,includingadrawing.Presentyourreporttoyourpatrolortroop.
(2) Doresearchononespeciesthatwasendangeredorthreatenedbutwhichhasnowrecovered.Findouthowtheorganismrecovered,andwhatitsnewstatusis.Writea100-wordreportonthespeciesanddiscussitwithyourcounselor.
(3) Withyourparent’sandcounselor’sapproval,workwithanaturalresourceprofessionaltoidentifytwoprojectsthathavebeenapprovedtoimprovethehabitatforathreatenedorendangeredspeciesinyourarea.Visitthesiteofoneoftheseprojectsandreportonwhatyousaw.
F. PollutionPrevention,ResourceRecovery,andConservation
(1) Lookaroundyourhomeanddetermine10waysyourfamilycanhelpreducepollution.Practiceatleasttwoofthesemethodsforsevendaysanddiscusswithyourcounselorwhatyouhavelearned.
(2) Determine10waystoconserveresourcesoruseresourcesmoreefficientlyinyourhome,atschool,oratcamp.Practiceatleasttwoofthesemethodsforsevendaysanddiscusswithyourcounselorwhatyouhavelearned.
(3) Performanexperimentonpackagingmaterialstofindoutwhichonesarebiodegradable.Discussyourconclusionwithyourcounselor.
EnvironmEntal SciEncE 5
4. Choosetwooutdoorstudyareasthatareverydifferentfromoneanother(e.g.,hilltopvs.bottomofahill;fieldvs.forest;swampvs.dryland).ForBOTHstudyareas,doONEofthefollowing:
A. Markoffaplotof4squareyardsineachstudyarea,andcountthenumberofspeciesfoundthere.Estimatehowmuchspaceisoccupiedbyeachplantspeciesandthetypeandnumberofnonplantspeciesyoufind.Writeareportthatadequatelydiscussesthebiodiversityandpopulationdensityofthesestudyareas.Discussyourreportwithyourcounselor.
B. Makeatleastthreevisitstoeachofthetwostudyareas(foratotalofsixvisits),stayingforatleast20minuteseachtime,toobservethelivingandnonlivingpartsoftheecosystem.Spaceeachvisitfarenoughapartthattherearereadilyapparentdifferencesintheobservations.Keepajournalthatincludesthedifferencesyouobserve.Then,writeashortreportthatadequatelyaddressesyourobservations,includinghowthedifferencesofthestudyareasmightrelatetothedifferencesnoted,anddiscussthiswithyourcounselor.
5. Usingtheconstructionprojectprovidedoraplanyoucreateonyourown,identifytheitemsthatwouldneedtobeincludedinanenvironmentalimpactstatementfortheprojectplanned.
6. Findoutaboutthreecareeropportunitiesinenvironmentalscience.Pickoneandfindouttheeducation,training,andexperiencerequiredforthisprofession.Discussthiswithyourcounselor,andexplainwhythisprofessionmightinterestyou.
EnvironmEntal SciEncE 7
contents
WhatIsEnvironmentalScience? . . . . . . . . . . . . . . . . . . . . . . 9
TheRootsofEnvironmentalScience . . . . . . . . . . . . . . . . . . 12
PrinciplesofEcology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
HumanImpactontheBiosphere. . . . . . . . . . . . . . . . . . . . . 33
TakingAction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
CareersinEnvironmentalScience. . . . . . . . . . . . . . . . . . . . . 68
ActivitiesinEnvironmentalScience. . . . . . . . . . . . . . . . . . . 71
EnvironmentalScienceResources. . . . . . . . . . . . . . . . . . . . . 93
EnvironmEntal SciEncE 9
.What Is Environmental Science?
WhatIsEnvironmentalScience?Scientistsaskquestionsaboutthingstheyobserveandthentrytofindouttheanswers.Anenvironmentalscientistasksques-tionsabouttheenvironmentandtriestolearntheanswersbyobservingandexperimenting.WhileearningtheEnvironmentalSciencemeritbadge,youwillgetatasteofwhatitisliketobeanenvironmentalscientist,asyoumakeobservationsandcarryoutexperimentstocompletetheactivitiesandprojectsrequiredforthebadge.
From nature Study to EcologyPeoplehavealwaysbeencuriousaboutthenaturalworldandhavestudieditinordertosurvive.Earlyhumanslearnedwhichplantsweregoodtoeatandwhichonesmadethemsick.Theylearnedthehabitsofanimalsthattheyhuntedforfoodandhowtoavoidthoseanimalsthatpreyeduponhumans.
Today,manypeopleobserveplantsandanimalsinthewildasahobby.Somegohikingtofindrarewild-flowers.Otherskeepbinocularsandfieldguidesnearawindowsotheycanidentifythebirdsthatvisitbackyardbirdfeeders.Becausemanypeopleoverthecenturieshavestudiednatureclosely,muchisknowntodayaboutthenaturalhistoryofplantsandanimals.
Plantsandanimals,however,donotlivealoneintheenvironment.Alivingthing’senvironmentismadeupofallofthelivingandnonlivingmaterialsaroundit,includingplants,animals,air,soil,heat,light,food,water,andanythingelsethatplaysanyroleinitslife.Inaddition,allplantsandanimalsareconnectedtootherlivingthings.
The natural
development of
a living thing over
time is its natural
history. People
who study
natural history
are naturalists.
10 EnvironmEntal SciEncE
What Is Environmental Science?.
Theyinteractwithoneanotherandwiththenonlivingpartsoftheirenvironment.Livingthingsdependuponthematerialsfoundintheirenvironmenttosurvive.Anythingthatdisturbstheenvironmentmayaffectthelivingthingsfoundthere.
Using this PamphletAnenvironmentalscientistneedstoknowagreatdealaboutlivingthings,abouttheirwaysoflife,andabouttheenvironmentanditseffectonlife.Forinstance,anenvironmentalscientistmightstudyhowthechemistryofsoilaffectsantbehavior.Someotherthingsthatanenvironmentalscientistmightstudyincludeplantsinaforest,makeupofrainwater,purityofair,andhowmanylivingthingsarefoundinagivenenvironment.Theactivitiesinthispamphletwillintroduceyoutothewiderangeofsubjectsthatenvironmentalscientistsstudy.
The study of
living things and
their interactions
with one another
and with their
environments is
known as ecology.
Scientists
who study the
interactions
among organisms
and their
environments
are ecologists.
EnvironmEntal SciEncE 11
.What Is Environmental Science?
Steps in the Scientific MethodImagine that you are watching a line of ants carrying pieces of food from a picnic site to an anthill. If you push the ants aside, they soon line up again. You want to know how the ants know where to line up. To try to answer that question, you follow a series of steps known as scientific method.• First, you state the problem you want to solve—how
ants know where to line up. Then you gather informa-tion about ants. Perhaps you do some research on ants in the library.
• Next, you form a hypothesis, that is, you formulate a statement or question that can be tested. Your hypothesis might be a statement such as: Ants know where to line up because they can see one another.
• You test your hypothesis by performing an experiment. In your experiment, you place food in one corner of a box and ants at the other end. When the ants have found the food and have formed a line to carry it, you disrupt the line, and then turn off the lights.
• Now you analyze your results. Did the ants line up again? If the ants lined up even in the dark, you might draw a conclusion that they do not need to see one another in order to line up, so your hypothesis is wrong. Your conclusion would be that ants must use some sense other than sight to line up. Sometimes, when the results of an experiment do not support a hypothesis, you can use what you learned to formu-late a new hypothesis and carry out a new experiment to test the new hypothesis.
Not all hypotheses can be tested by doing an experi-ment in a laboratory. Some hypotheses are tested by observing events and collecting facts. You could test which kinds of birdseed a particular type of bird prefers just by observing what birds eat at several feeders.
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The Roots of Environmental Science.
TheRootsofEnvironmentalScienceAmericanIndiansusedforestsandotherenvironmentalresourcesforcenturiesbeforeEuropeansettlersarrivedonthecontinent.InthePacificNorthwest,tribesusedforestmaterialstomakecedarhouses,boats,andclothing.IntheNortheastandupperMidwesttheybuiltbirch-barkcanoes.Forestsalsoweretremen-doussourcesoffood,bothfromplantsandfromwildlife.
Attimes,tribesoverusedcertainforestedareas.Sometimestheyintentionallyburnedforeststoclearlandforcultivationortomakeiteasiertopursuegame.Ifaforestbecameoverusedortooheavilydamagedtosupportatribe,thegroupwouldmoveonandtheforest,leftalone,wouldrecover.
AsmoreandmoreEuropeansettlersarrivedinNorthAmerica,theirneedfornaturalresourcesgrew.Theykilledwildlife,cuttrees,andcontaminatedthewaterneartheirsettle-ments.Whenthepressureonnaturalresourcesinasettledareagrewtoogreat,peoplemovedwestwardandbeganthecycleagain.Settlersbelievedtheycouldalwaysmovefartherwesttofindmorespaceandmoreresources.
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.The Roots of Environmental Science
Earlyon,however,somesettlersrealizedthattheabundantnaturalresourcesofthisnewlandwerenotlimitless.In1626,PlymouthColonypassedalawtocontrolthecuttingandsaleoftimberoncolonylands.PeopleinNewport,RhodeIsland,agreedin1639torestrictdeerhuntingtosixmonthsayear.InPennsylvaniain1681,WilliamPenndecreedthatoneacremustbeleftforestedforeveryfiveacresofforestthatwerecleared.
Bythe1830s,peoplesuchasartistGeorgeCatlinandnaturalistHenryDavidThoreauwerewritingabouttheneedtopreservesomeoftheuniqueenvironmentsofNorthAmericainnationalparks.PeoplededicatedtoenvironmentalprotectionandwildlifeconservationfoundedgroupssuchasAmericanForests(1875),theAppalachianMountainClub(1876),theNewYorkAudubonSociety(1886),theBooneandCrockettClub(1887),theSierraClub(1892),theAmericanScenicandHistoricPreservationSociety(1895),andtheIzaakWaltonLeagueofAmerica(1922).
Governmentmanagementofspecialareascanbetracedbacktothecreationofthefirstnationalpark—Yellowstone—setasidein1872.CongresspassedtheCreativeActin1891,designatingmuchofthenation’spubliclyownedforestsasprotectedforestreserves.TheForestReserveActof1891followed,changingtheforestreservestonationalforestsandchargingtheirmanagerswithimprov-ingandprotectingthenation’slong-termsupplyofwoodandwater.TheBureauofForestrybecametheForestServicein1905whentheforestreservesweretransferredtotheDepartmentofAgriculture.In1916,CongressestablishedtheNationalParkService.TheParkService’smissionistopreservenaturalandculturalresourcesfortheenjoyment,education,andinspirationofcurrentandfuturegenerations.
Inthedecadesthatfollowed,forward-thinkingagencypersonnelandaconservationmovementmadeupofdedicatedcitizensestablishedtheideaofprotectingsomeforestsandotherwildernessareasasremindersofthewaytheywerebeforehumansintervenedandofbalancingtheuseofpubliclandsforrecreation,timber,andbiologicalresources.TheMultiple-UseSustained-YieldActof1960officiallyestablishedmultiple-usemanagementoftheforests.
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The Roots of Environmental Science.
TheBureauofLandManagement,theU.S.ArmyCorpsofEngineers,theFishandWildlifeService,theNaturalResourcesConservationService,andotherpublicagenciesalsostrivetomanagepubliclandsthatfallwithintheiradministrativebound-aries.Stateandlocalagenciesoverseesmalleracreagesofpub-liclands.Privatelandownerswithforestedproperties—fromlargeforest-productcompaniestofamilieswithafewacresoftreesaroundtheirhomes—haveastakeinthepropermanage-mentofforestresources,too.
From conservation to EnvironmentalismDuringthelate1800sandearly1900s,peoplebegantospeakoutabouthumanactivitiesthatwerecausingseriousenviron-mentalproblemssuchasairandwaterpollution.AmericanzoologistWilliamT.HornadaywroteabouttheneedtoprotectwildlifeinNorthAmerica.In1907,ascientificstudybyM.C.Marshshowedhowfishwerehurtbyindustrialwastesreleasedintowatersources.In1962,RachelCarsonpublishedSilent Spring,abookthatdiscussedthedangerstotheenvironmentfromusingthepesticideDDT.
The Slaughter of the BisonHuge herds of millions of bison, or American buffalo, were once a common sight on the Great Plains. By 1884, however, settlers had hunted so many of them that only 300 were left. The survival of the bison is largely credited to the efforts of Dr. William T. Hornaday, who led conservation efforts to protect the bison. Today, Scouts can earn the William T. Hornaday Award for distinguished service in conservation.
EnvironmEntal SciEncE 15
.The Roots of Environmental Science
Carsonandotherpeoplewhowroteabouttheenvironmen-taleffectsofhumanactivitieshelpedmakethepublicawareofenvironmentalconcerns.ThispublicawarenessledtothedesignationofApril22asEarthDay.ThefirstEarthDayin1970sparkedanenvironmentalmovementintheUnitedStates.Asaresult,theU.S.EnvironmentalProtectionAgency(EPA),theCouncilonEnvironmentalQuality,andmanystateandlocalenvironmentalagencieswereestablished.Today,manylawsprotectourair,water,land,andwildliferesources.
Boy Scouts and the EnvironmentIntheearly1900s,astheconservationmovementgrew,twoseparateorganizationsforboysthatfocusedonnatureandtheenvironmentwerefounded.In1902,theWoodcraftIndianswasstartedinConnecticutbythenaturalistErnestThompsonSetontopreservethewildernessknowledgeofAmericanIndians.Asoneoftheforemostnaturalistsofhistime,SetonspokebeforetheU.S.Congressin1904insupportoflegislation,whichhadbeenauthoredbyWilliamT.Hornaday,toprotectmigratorybirds.
Aboutthesametime,DanielCarterBeard,aformersur-veyorandengineerwhobecameanauthorandillustrator,wroteabooktitledThe American Boy’s Handy Book.In1905,BeardfoundedaclubcalledSonsofDanielBoonetoteachboysaboutnature,conservation,andoutdoorsmanship.
OnFebruary8,1910,SetonandBeardmergedtheirseparateboys’clubsintotheBoyScoutsofAmerica.PublisherWilliamD.Boycefoundedthisneworganization.Fromitsbeginnings,theBoyScoutsofAmericahadastrongfoundationofwoodcraft,naturestudy,andconservation.ManyactivitiesinScoutingcomefromactivitiesofAmericanIndians.ManyoftheprinciplesthatScoutsupholdcomefromtheconservationethicsofSetonandBeard.TheBSAhastaughtmorethan45millionyoungenvironmentaliststhroughoutitshistory.Currently,withmorethan1.5millionactivemembers,theBSAcontinuestotrainAmericanyouthinprinciplesofconservationandenvironmentalscience.
Activities
designed to help
you earn the
Environmental
Science merit
badge can be
found toward
the back of
this pamphlet.
EnvironmEntal SciEncE 17
.Principles of Ecology
PrinciplesofEcologyAlthoughlawsandagencieshavebeenestablishedtohelpprotectandpreservenature,muchmoreneedstobedone.Beforeyoucanhelpprotectnature,youmustunderstandhowitworks.
Understanding EcologyImaginethatyouarestandingonthebankofaquietriverinFlorida.Alongthebanksofthisriveryouseeagreatblueheron,analligator,aratsnake,andaraccoon.Onarockintheriver,aFloridared-belliedturtlebasksinthesun.Lookingdownintothewater,youseethelongbodyofafishcalledagarglidingthroughslenderleavesofeelgrass.Snailsfeedastheytravelamongthewaterplants.Hereandthere,whirligigbeetlesdotthewatersurface.Tinyduckweedplantsfloatnearthequietbanks.Abullfrogjumpsfromtheriver’sedgeanddisappearsintothewater.
Allofthelivingthingsinandaroundtheriverarecon-nectedinsomeway.Bullfrogseatwhirligigbeetles.Heronseatbullfrogs,ratsnakes,gars,andhatchlingred-belliedturtles.Raccoonseatbullfrogs,insects,worms,andsnails.Snailsandadultturtleseataquatic(water)plants.Innature,livingthingsinteractinmanyways.
living things in the EnvironmentSnails,red-belliedturtles,andeelgrassarelivingthings.Allliv-ingthingshavetheabilitytoreproduce,thatis,tomakemoreofthesamekindoflivingthing.Livingthingsalsochangedur-ingtheirlifetimes.Theygrowanddevelopandhavealifespanthateventuallyendsindeath.Anotherimportantcharacteristicoflivingthingsisthattheycanusuallyadjusttotheirsurround-ings.Theycanrespondtochangesintheirenvironments.
Principles of Ecology.
Scientistscalllivingthingsorganisms.ThinkofallthemillionsoforganismsthatinhabitEarth.Organismscanbefoundinthedeepestoceansandonthehighestmountains.SomebacteriacanevenbefoundhighinEarth’satmosphere.ThepartofEarththatcontainsandsupportslivingthingsisknownasthebiosphere.ThebiosphereisallpartsofEarthwherelifeexistsonland,inwater,orintheair.
Withinthebiospherearemanydifferentkindsofenviron-ments.Beaches,forests,glaciers,deserts,andriversareenvi-ronments.EveryenvironmentonEarthincludesboththelivingthingsfoundthereandthephysical,ornonliving,environment
the organisms that live in and around a river in Florida include fish, amphibians, reptiles, birds, mammals, and plants.
HydrospHere
LitHospHere
AtmospHere
the regions that form Earth’s biosphere include the atmosphere (air), hydrosphere (water), and lithosphere (land).
18 EnvironmEntal SciEncE
EnvironmEntal SciEncE 19
.Principles of Ecology
inwhichlivingthingsexist.Thinkaboutthelivingthingsinyourownenvironment.Nomatterwhereyoulive,organismssurroundyou.You,thebacteriaonyourskin,yourpet,thefleasonyourpet,thespiderinacorner,andtheplantsgrowingoutsideareorganismsinyourenvironment.
Youhaveinteractionswiththebacteria,yourpet,itsfleas,thespider,andtheplants,buttheseinteractionsarenottheonlyonesinyourenvironment.Therealsoarenonlivingthingsthatinfluencetheorganismsineveryenvironment.
nonliving things in the Environment Let’sgobacktothatFloridariveryouimaginedbeforeandthinkofnonlivingthings.Youprobablyknowthatthewaterintheriverisnonliving,butwhataboutthewind?Thesunlight?Rocksintheriver?Thesoilthatsupportstheplantsgrowingattheriver’sedge?Theseareallnonlivingthingsthatinteractwiththelivingorganismsintheriverenvironment.
Inyourenvironment,theweatheraffectsyouandyourpets.Thesoapyouusewhenyoushoweraffectsthebacteriaonyourskin.Sunlight,temperature,rainfall,andmineralsinthesoilaffecttheplantsoutside.Theimportantinteractionsbetweennonlivingandlivingthingsdeterminewhichlivingthingscanshareanenvironmentwithwhichnonlivingthings.
Let’slookatfournonlivingfactorstofindouthowtheyaffectthelivingthingsinanenvironment.
Water.LifeonEarthwouldbeimpossiblewithoutwater.Thebodiesofmostorganismsare50to95percentwater.Waterisnecessaryformanylifeprocesses,includingrespira-tion,photosynthesis,anddigestion.
Watercoversmorethan70percentofEarth’ssurface.Butabout97percentofthewateronEarthissaltwatercon-tainedinoceans.Thatmeansonlyabout3percentisfresh-water.Mostofthefreshwaterisnotavailabletolivingthings,becauseitisfrozenintheicecapsorglaciers.Infact,onlyatinyfractionofEarth’swaterisfreshwaterthatisavailabletoorganisms.Thisfreshwaterisinrivers,ponds,lakes,streams,undergroundwatersupplies(aquifers),orinwatervapor.
20 EnvironmEntal SciEncE
Principles of Ecology.
Soil. Soilisformedbythephysicalandchemicalbreakdownofrocksandbytheactionsoflivingthings.Thebreakdownofrockintosoilreleasesmineralsthatorganismsneedfortheirlifeprocesses.Thesemineralsreturntothesoilwhenorganismsdieanddecay.Decayedmaterialthatoncewaslivingiscalledorganicmatter.Themoreorganicmatterinsoil,themorefertileitis.
Soildeterminesthetypeofplantlifethatcangrowincer-tainenvironments.Therefore,soilhasaneffectupontheotherorganismsthatcanlivethere,too.Amongthefactorsthatdeter-minewhichorganismscanliveinaparticularsoilenvironmentarethemineralandorganicmattercontent,aircontent,andsoiltexture.
In photosynthesis,
green plants,
algae, and some
other organisms
capture the
energy of sunlight
and change it into
a form of energy
that they can use
or store. Most
of the energy
that powers
life in Earth’s
biosphere is made
available through
the process of
photosynthesis. ToTal WaTer on earTh
sALt wAter (oceAns)
97.2 percentFresHwAter (LAkes,
rivers, streAms) 0.022 percent
ice cAps And gLAciers 2.38 percent
groundwAter 0.397 percent
AtmospHeric wAter vApor
0.001 percent
100 percent 26 gALLons
3 percent 0.8 gALLons
0.003 percent 1⁄2 teAspoon
How much of Earth’s freshwater is available for organisms? if you imagine that Earth has a total of 26 gallons of water, less than one gallon of that would be freshwater, and only half a teaspoon would be readily available to living things.
EnvironmEntal SciEncE 21
.Principles of Ecology
Sunlight. Nearlyalllivingthingsdependuponthesunforenergy,eitherdirectlyorindirectly.Plants,algae,andsomeotherorganisms“trap”sunlightandcaptureitsenergyintheprocessofphotosynthesis.Plantsusethisenergytopowertheirlifeprocesses,ortheystoreit.Whenasnaileatsaplant,forexample,thesnailusesthestoredenergyintheplanttocarryoutlifeprocessessuchasbreathingandmoving.Whenarac-cooneatsthesnail,theenergyispassedalong.Greenplants,algae,andotherphotosyntheticorganismsmustlivewherethereissunlight.Inaquaticenvironments,photosyntheticorganismscanliveonlyinthetoplayerofthewater,wheresunlightcanreachtheorganisms.
temperature. Ingeneral,thetemperatureofanenvironmentdependsontheamountofsunlightitgets.Airisheatedmoreattheequatorthanatthepoles.Thisiswhytropicalareasneartheequatorarehot,thepolarregionsarecold,andtheregionsinbetweenhavemoderatetemperatures.TemperaturesalsoareaffectedbyEarth’srotation,bywindsandoceancurrentscreatedbythatrotation,bythetiltofEarthonitsaxis(seetheillustration),andbyelevation.Asyouhikeupamountain,theairtemperaturedrops.ThatiswhyitispossibletohaveasnowballfightontopofMountBaldyatPhilmontScoutRanchinNewMexicoinJuly!
Factors such as
rainfall, sunlight,
temperature,
the nearness of
large bodies of
water (oceans),
and elevation
determine the
climate (the
general weather
pattern) in
an area.
Earth’s orbit
Spring
Summer
WinTer
auTumn
sun
s u n
s u n
s u n
s u n
n n n n
s s s s
S
n
S
n
S
n S
n
22 EnvironmEntal SciEncE
Principles of Ecology.
interactions among living things ThinkagainoftheorganismslivinginaFloridariver.Thereareseveraldifferentspeciesofturtleslivingthere.Aspeciesisagroupoforganismsthathascharacteristicsincommonandcanbreedtoproduceoffspring.Forexample,red-belliedturtlescanmatewithotherred-belliedturtlestoproducebabyred-belliedturtles.Intheriver,thereareatleastthreespeciesofturtles—red-belliedturtles,cooters,andcommonsnappingturtles.Alltheindividualred-belliedturtleslivingintherivermakeupapopulationofred-belliedturtles.Allthecootersmakeupapopulationofcooters,andallthesnappingturtlesmakeupapopulationofsnappingturtles.Youcanseethattheriverenvi-ronmentcontainsmanydifferentpopulationsoforganisms.
Populationsoforganisms,ofcourse,donotlivealoneintheenvironment.Mostinteractwithotherpopulationsinagivenarea.Thered-belliedturtlesinteractwiththeeelgrass(byeatingit).Theeelgrassprovideshidingplacesforyoungfishandtadpoles.Thegreatblueheronseatthebullfrogs.Populationsareconstantlychanginginsize,density,andageastheyrespondtochangesintheirenvironment.Iftheheronseatalloftheadultbullfrogsintheriver,forexample,thepopulationofbullfrogswillincludeonlytadpolesandeggs.
a pond ecosystem
EnvironmEntal SciEncE 23
.Principles of Ecology
Groupsofpopulationsthatinteractwithoneanotherinagivenareaformacommunity.Allthepopulationsinacommunitydependupononeanotherforneedssuchasfoodandshelter.Thepopulationsoforganismsthatlivetogetherandinteractwithoneanother—suchasherons,alligators,bullfrogs,insects,andturtles—formtheFloridariver’slivingcommunity.Theriver,thesoilalongthebank,therocksintheriver,andthesunshiningontheriveraresomeofthenonlivingfactorsintheenvironment.
Thelivingcommunityoftheriver,andthenonlivingfactorsthataffectit,formrelationshipsthattogethermakeupanecosystem.Ecosystems,suchasariver,pond,forest,ordesert,maybetreatedasseparatepartsoftheenvironment.
relationships Within EcosystemsWithinanecosystemsuchasaFloridariver,theactionsofeveryspeciesaffectotherspecies,populations,andcommuni-ties.Aratsnakefeedsonsmallrodents,keepingtherodentpopulationsmallenoughthattheydonoteatalltheplantseedsavailable.Analligatorstirsupbottommud,releasingwormsandorganicmatterthatotherorganismsuseforfood.Bothratsnakesandalligatorshelpmaintaintheirecosystems.
the living community in a Florida river includes many populations that live together and interact with one another. the river, the soil along its bank, and the sun shining on the water are some nonliving factors in the environment.
24 EnvironmEntal SciEncE
Principles of Ecology.
niches and HabitatsAnicheistheroleofaspeciesinitscommunity.Thenicheoffungisuchasmushrooms,forexample,isnotsimplytogetnutrients(food)fromdeadordyingtreesbutalsotoreleasethosenutrientsbackintotheenvironmentinaformthatotherorganismscanuse.
Besideshavingarolewithinacommunity,organismsoccupyspace.Forinstance,youliveinahouse,anapartment,orsomeothertypeofshelter.Inariverecosystem,greatblueheronsroosthighintreesalongriverbanks.Commonsnappingturtlesburrowintothemudatthebottomofariver.Theplaceinwhichanorganismlivesisitshabitat.Anorganism’shabitatprovidestheorganismwithnourishment(foodandwater),shelter,protectionfromenemies,andthespaceneededforthatorganismtosurvive.
Withinanyhabitat,thefood,shelter,andotherresourcesaredividedintoseparateniches.Forexample,aFloridariverisahabitatforbothred-belliedturtlesandbullfrogs.Adultturtleseatonlywaterplants.Bullfrogseatinsects,snails,fish,andfrogs.Becausethesetwospecieseatdifferentfoods,theyoccupydifferentnicheswithinthesamehabitat.
EnvironmEntal SciEncE 25
.Principles of Ecology
Feeding relationships Manyoftherelationshipswithinacommunityarefeedingrela-tionships.Thatisbecauseanimalsmusteattogettheenergytheyneedforlife.AlmostalltheenergyonEarthbeginswiththesun.Organismssuchasgreenplantsandalgaetrapthesun’senergyduringtheprocessofphotosynthesis.Theseorgan-ismsarecalledproducers.Allotherorganismsdependuponproducersforenergy.
Someorganismsgettheenergytheyneedbyeatingplantsandotherproducers.Miceandrats,forexam-ple,gettheirenergybyeatingplantseeds.Otherlivingthingsgetenergybyeatingorganismsthateatplants.Ratsnakes,forexample,eatthemiceandratsthateatplantseeds.Organismssuchasmice,rats,andratsnakesarecalledconsumers.
Organismsthatbreakdowndeadplantandanimalmatterandabsorbenergyandnutrientsfromthemarecalleddecom-posers.Bacteria,earthworms,andmostfungiaredecomposers.Whentheybreakdownthebodiesofdeadorganisms,theyusesomeoftheenergyandnutrientsfortheirownlifeprocessesbutalsoreturnenergyandnutrientstothesoilasorganicmatter.
Producer, consumer,anddecomposeraretermsecologistsusefordifferentnicheswithinanecosystem.Theserolesareimportantforanecosystemtofunction.Ecologistsfurtherdividethesenichesintofeedingrelationships.Youprobablyarealreadyfamiliarwithafeedingrelationshipknownasthepredator-preyrelationship.Ratsnakes,herons,alligators,andfrogsallare
26 EnvironmEntal SciEncE
Principles of Ecology.
predatorsthateatprey.Otherfeedingrelationshipsincludeparasite-hostrelationships,suchasamosquito(theparasite)feedinguponyourblood(youarethehost).
Therearemanyothertypesofrelationshipswithinandbetweenecosystems.Sometimes,organismsofdifferentspecieslivetogetherbutdonotfeeduponeachother.Thisiscalledsymbiosis,whichmeans“livingtogether.”Clownfish,forexample,liveamongthestingingtentaclesofseaanemones.Thesetwoanimalshaveasymbioticrelationship.Scientistsbelieveaclownfishdevelopsimmunitytothestingofapartic-ularseaanemone.Yetpredatorfisharenotimmune,sotheclownfishisprotectedfrompredatorswhenitswimsbetweenthestingingtentaclesoftheseaanemone.Theseaanemonebenefitsbecausetheorange-stripedclownfish,whichisverynoticeableandapparentlysafeswimmingamongthepoisonoustentacles,luresinotherspeciesoffish.Theseaanemonestingsandeatstheunsuspectingfishthatcometooclose.
the sea anemone and clown fish have a symbiotic relationship—they are partners, helping each other survive.
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.Principles of Ecology
Producer, Consumer, or Decomposer?
Which of these organisms are producers? Which are consumers? Which are decomposers?
28 EnvironmEntal SciEncE
Principles of Ecology.
cycling of matter through EcosystemsEverylivingandnonlivingthingismadeofmatter.Matteristhephysicalmaterialthatmovesthroughanecosystemandisrecycledinanecosystem.
the Water cycleEnergyfromsunlightisconstantlyrenewedorreplenishedinanecosystem.Matterisnotreplenished.Allofthephysicalmate-rialinyourbodyandinthebodiesofallorganismsisthesamematterthathasbeenonEarthsincelifebegan.Let’sseehowthesephysicalmaterialsarerecyclednaturallyinecosystems.
Watercirculatesthroughtheenvironmentinaprocessknownasthewatercycle.Heatfromthesunevaporateswaterfromoceans,lakes,andstreamsthatformscloudsofwatervaporintheatmosphere.Eventually,thevaporcondensesandfallsasrain,snow,sleetorhail—calledprecipitation.
Of all the natural resources neccesary to the existence and comfort of all living things on Earth, water is the arguably the most important.
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Someprecipitationpercolatesintothesoilwhereplantrootscanabsorbit.Someofthewaterseepsdownthroughthesoilandfindsitswayintoaquifers(undergroundlayersofporousrockthatserveasnaturalstorageareasforgroundwater).Somerainwaterfindsitswayintosurfacewatersuchasstreamsandlakes.Surfacewatereventuallyevaporates,enterstheatmosphere,condenses,andfallsagainasprecipitation.Waterisnotusedup;itisjustreusedoverandover.
Livingorganismsalsoplayaroleinthewatercycle.Plantsabsorbwaterfromthesoilthroughtheirrootsandreleasewatervaporintotheairthroughaprocesscalledtranspiration.Animalsdrinkwaterdirectlyfromlakesandstreamsorgetitfromthefoodstheyeat.Animalslosewaterthroughexcretion.Bothplantsandanimalsalsolosewatertotheatmospherethroughrespiration.Whenorganismsdie,theirbodiesreleasewatertotheenvironmentastheydecompose.
precipitAtion (rAin)
cLoud FormAtion
trAnspirAtion
evAporAtion
surFAce runoFF
groundwAter
percoLAtion (soAk-in)
streAm to oceAn
the water cycle
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Principles of Ecology.
the oxygen-carbon cycleAlllivingthingsneedcarbon.Plantsusecarbondioxideandwaterintheprocessofphotosynthesistomakeatypeofsugarthatlivingthingsuseforenergy.Consumersgetcarbonwhentheyeattheproducersandthenusethecarbonintheirlifeprocesses.Bybreathing,animalsreleasecarbondioxideintotheatmosphere.Decomposersreleasecarbonastheybreakdownthebodiesofdeadorganisms.Thecyclebeginsanewasproducersusethecarbonfromtheairtomakefood.
Organismsdonotalwaysdecayrightaway.Theymayfallintoswampyorboggyareaswithlittleoxygen.Ifdecayhap-penswithoutoxygen,eventuallycarbonmaybeboundintoafossilfuel—suchascoal,oil,ornaturalgas.Scientistsbelievethattinyplantsandanimalsthatdiedthousandsofyearsagoarewhatformedthefossilfuelsweusetoday.Theburningoffossilfuelsreturnscarbontotheatmosphereinlargeamounts.
Carbon, like other
matter, must be
recycled through
the biosphere for
use by organisms.
sun energy
pLAnt growtH
soiL nutrients
decAying mAtter
Food From AnimALs
And otHer products
oxygen
Food From
pLAnts
AnimAL Food
cArbon dioxidecArbon d
ioxid
e
the oxygen-carbon cycle
pLAnt Food
EnvironmEntal SciEncE 31
.Principles of Ecology
the nitrogen cycleAirisnearly78percentnitrogen.Alllivingthingsneednitro-gen,butmostcannotusenitrogenintheair.Organismsneednitrogeninaformcallednitrates,inwhichnitrogenisbondedtooxygenandanotherelement.Nitrogenintheairischangedintonitratesbylightningandbycertainsoilbacteriaorplants.Plantsthentakeupthenitratesfromthesoilandpassthemalongtoconsumers.
Some environments may have so little moisture or bacteria that they require an outside influence, such as a fire, to begin the decomposition process.
When organisms die and decompose, they release nitrogen into the atmosphere, soil, and water, and the cycle begins again.
the nitrogen cycle
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HumanImpactontheBiosphereThinkaboutthethingsyoudoeverymorningtogetreadyforschool.Youwakeupasthesunfiltersthroughthewindow.Youtakeashowerandputonyourclothes.
Doyourealizethatyouusenaturalresourceseverymorn-ing?Thesun’senergyisanaturalresource.Thewaterforyourshowerisalsoanaturalresource,asisthesoilthatgrewthecottonusedtomakeyourclothes.
What are natural resources?Natural resourcesareallofthelivingandnonlivingfactorsinthebiosphere,includingnutrients,minerals,soil,water,organisms,andotherresourcesmadebynaturalprocessesonEarth.Theyarethematerialsthatyouandalllivingthingsuseeveryday.
Somenaturalresourcescanbeusedoverandover.Suchresourcesareknownasrenewable resources.Naturalprocessesreplenishrenewableresources.Renewableresourcesincludefreshwater,freshair,soilfertility,forests,andelementssuchascarbonandnitrogen.Nonrenewableresourcesexistinlimitedamountsandarenotreplacedthroughnaturalprocesses.Theyincludepetroleum,coal,naturalgas,copper,aluminum,andtheproductsmadefromtheseresources.
Some resources are replaced so slowly by natural processes that they can be thought of as nonrenewable. Topsoil (the most fertile layer of soil) is an example of a resource that is renewable by natural processes, such as weathering, but topsoil formation takes so long that we think of topsoil as nonrenewable. It may take 500 to 1,000 years for one inch of topsoil to form.
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Problems With resource UseAllorganismsproducewasteproducts.Duringphotosynthesis,plantstakeincarbondioxideandgiveoffoxygenasawasteproduct.Youbreatheinoxygenandbreatheoutcarbondioxideasawasteproduct.Whenyoueatahardboiledeggoranorange,theeggshellandtheorangepeelarewaste.Decomposersinthesoilcanbreakdowneggshellsandorangepeelsintothenutri-entsplantsneed.Orangepeels,eggshells,oxygen,andcarbondioxideallarewasteproducts,buttheycanberecycledinthebiospherebynaturalprocesses.
Whathappenswhenwasteproductsareproducedtooquicklyorinamountstoogreattoberecyclednaturally?Whenwasteproductsbuildupfasterthantheycanbebrokendown,theybecomepollutants.
Here are some items made from natural resources. can you identify which of these are made from renewable resources and which are made from nonrenewable resources?
Renewable or Nonrenewable?
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Stratosphere
Mesosphere
Thermosphere
Troposphere
Sea Level
10
20
30(48 km)
(32 km)
(16 km)
50(80 km)
120(200 km)
air and air PollutionWhenyoubreathe,youexchangegaseswiththeair.Animals,includinghumans,takeinoxygenandbreatheoutcarbondioxide.
airThetwomostabundantgasesinEarth’satmospherearenitrogenandoxygen.Nitrogenmakesupabout78percentandoxygenanother21percent.Theremaining1percentconsistsoftraceamountsofothergases,includingcarbondioxideat0.036percent.Airalsoholdswatervapor.MostofEarth’sairisintheinnerlayeroftheatmosphere,calledthetroposphere.Abovethetroposphereisthestratosphere.
the layers of the atmosphere include the troposphere, stratosphere, mesosphere, and thermosphere. Beyond the thermosphere is open space. the ozone layer is in the stratosphere.
— ALso cALLed iono-spHere; tHe AurorA boreALis, or nortHern LigHts, HAppen Here.
— very coLd, -173 degrees FAHrenHeit.
— tHis LAyer contAins tHe ozone LAyer; weAtHer bALLoons reAcH tHis LAyer.
— tHis LAyer contAins 80 percent oF tHe AtmospHere’s mAss; it contAins dust, wAter vApor, And cLouds.
ALtitude (in miLes)
MOUNT EVEREST
AIR TRAFFIC
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Human Impact on the Biosphere.
the ozone layerAgascalledozoneformsinthestratospherewhenoxygeninteractswithlightningandultravioletradiationfromthesun.Ozoneisaformofoxygenthatconsistsofthreeoxygenmole-culesbondedtogether;theoxygenwebreatheconsistsoftwomoleculesbondedtogether.Ozoneisimportantbecauseitpre-ventsharmfulultravioletradiationfromreachingEarth’ssur-face.Ultravioletradiationharmshumansandotheranimalsbydamagingtheskin,eyes,andimmunesystem.Excessiveultravioletradiationalsoharmsplantsandaquaticorganisms.
the Greenhouse EffectOurclimateisregulatedbythegreenhouseeffect.HeatenergyfromthesunpassesthroughEarth’satmosphereandheatsEarth’ssurface.Someofthisheatenergyisradiatedbackupintotheatmosphere,wheregreenhousegasessuchascarbondioxideinthetroposphereabsorbheatfromthesunnearEarth’ssurface.ThisheatisthenreflectedbacktoEarth.Thisnaturalphenomenonisknownasthegreenhouseeffect,becausethegasesactlikethepanesofglassinagreenhouse,trappingthesun’swarmth.Withoutthegreenhouseeffect,thewholeworldwouldbeaboutthetemperatureoftheNorthPole.
reFLected rAdiAtion
escAping HeAt
AtmospHere
sHort wAveLengtH
rAdiAtion
Long wAveLengtH
rAdiAtion
trApped by
AtmospHere
eArtH
The ozone layer
occurs between
6 and 25 miles
above Earth.
the greenhouse effect
EnvironmEntal SciEncE 37
.Human Impact on the Biosphere
air PollutantsSomepollutantsentertheatmospherenaturally.Volcaniceruptions,duststorms,andforestfiresproducenaturalpollutants.Forexample,whenMountPinatubointhePhilippineserupted,theashesreducedtheamountofsunlightthatcouldpassthroughtheatmosphereandslightlyreducedEarth’saveragetemperatureforthreeyears.
Humanactivitiesalsocauseairpollution.Mostairpollutioncreatedbyhumanscomesfromburningfossilfuelsforenergy.Forexample,thesmokethatcomesfromtheexhaustpipeofacarorbuscontainssoot,ash,carbonmonoxide,arsenic,sulfur,andnitrogenoxidesasgasesandparticulates—tiny,solidparticlesofdust,ash,soot,orothervisiblepollutantsintheair.Particulatesinteractwithnitrogenoxidesandotherchemicalsintheairtoformadangeroustypeofairpollutioncalledsmog(from“smoke”and“fog”).Incitieswithheavytraffic,thegasesreleasedbycarsandtrucksproducesmog.Smogisespeciallydangerousforpeoplewithrespiratoryproblems.
Whenstudyingsourcesofairpollution,suchasthesmokefromafactory,environmentalscientistsareconcernednotonlyabouttheareaimmediatelysurroundingthefactory,butalsowithamuchlargerareaknownasanairshed.Anairshedisanareathat,duetogeography,weatherpatterns,andclimate,sharesthesameair.Airpollutantstravel.Forexample,achemicalyousprayinyourgardenmaybetransportedonaircurrentsthroughouttheairshedaroundyourhouse.Inaddition,howapollutantisdistributedthroughanairsheddependsonthetypeofpollutant.Forexample,thewaypollutantsincarexhaustaredistributedwillbedifferentfromthewaythepollutantsfromaforestfirearedistributed.Scientistsusecomputermodelstotrytodeterminehowvariouspollutantsaffectairsheds.
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acid rainAcidityisapropertymeasuredonascalecalledthepHscale.Thescalehasarangeof0to14,with7beingneutral.PurewaterhasapHof7.IfasubstancehasapHbelow7,itisanacid.Rainisnaturallyslightlyacidic,withapHofabout5.6,becausecarbondioxideintheatmospherereactswithwatervaportobecomecarbonicacid.
Sulfurdioxideandnitrogenoxidesaretheprimarycausesofacidrain.Whenvehiclesandpowerplantsthatburnfossilfuelsemitsulfurdioxideandnitrogenoxidesintotheair,thesegasesinteractwithwatervaportoformsulfuricandnitricacids.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Acid neutrAL bAse
bAttery Acid
Lemon juice
tomAtoes miLk pure wAter
soAp soLutions
HAir remover
oven cLeAner
the pH of some common substances is shown on this scale.
acid rain can deplete the soil of the nutrients that plants need to grow. When acid rain falls, it filters down through the soil and dissolves soil nutrients and other materials, moving them down to layers out of reach of plant roots.
suLFuric Acid nitric Acid
suLF
ur d
ioxide
nitr
ogen oxide
Acid
pAr
ticL
es
Acid snow
Acid rAin
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
EnvironmEntal SciEncE 39
TheseacidsthenmixwithrainandfalltoEarth’ssurfaceasacidrain.AccordingtotheU.S.GeologicalSurvey,acidrainisrain(oranyothertypeofprecipitation)withapHlowerthan5.
Plantsmaydiefromacidrainorbeweakenedsothattheyaremoreeasilyharmedbyotherkindsofstressesintheenvironment,suchascoldtemperatures,insectdamage,ordroughts.AcidraindamagesaquaticecosystemsbychangingthepHofthewater.Manyaquaticorganismsmaydiewhenacidrainfallsintolakesandponds.
Acidrainisaworldwideproblembecausethegasesthatmakeitmaybeproducedinonestateorcountryandbeblowntoanotherstateorcountrybywinds.AcidrainthatfallsinsoutheasternCanadaandthenortheasternUnitedStates,forinstance,maybeginwithpollutantsemittedbycoal-burningpowerplantsasfarsouthasTennessee.
40 EnvironmEntal SciEncE
Human Impact on the Biosphere.
Global WarmingEarth’stemperatureisaffectedbyvariousfactors.Weaddheattotheairandwaterthroughthermalpollution.Increasedpar-ticulatesintheairreducetheamountofheatfromthesunthatcanreachus,andincreasedgreenhousegasestrapmoreheatonEarth.Sincethemid-20thcentury,manyscientistssay,humanactivitieshavereleasedmoreandmoregreenhousegases—particularlycarbondioxide,methane,nitrousoxide,andchlorofluorocarbons—intotheatmosphere.
• Carbon dioxideisreleasedduringforestfiresandinlargeamountsbytheburningoffossilfuels,especiallycoal.
• Methaneoccursnaturallyasacomponentofnaturalgas.Italsoisproducedasbacteriadecomposeorganicwasteintheabsenceofoxygen.Thisgastrapsmorethan20timesasmuchheatasdoescarbondioxide.Landfills,whichcontainlargeamountsoforganicwaste,areamajorsourceofmeth-ane.Livestocksuchascattlealsoproducemethaneduringtheirdigestiveprocesses.Thebreak-downofanimalmanurefromcattle,hogs,andpoultryisanothersourceofmethane.
• Nitrous oxideisapollutantthatformsduringforestfires,whencoalisburnedandwhennitrogenfertilizersbreakdowninsoil.Nitrousoxidetrapsabout230timesasmuchheatasdoescarbondioxide.
• Chlorofluorocarbons (CFCs)wereonceusedaspropellantsinspraycansandascoolantsinrefrigeratorsandairconditioners.CFCstrapthousandsoftimesmoreheatthandoescarbondioxide.MostusesofCFCsarenowbanned.However,sinceittakes10to20yearsforCFCstoreachthestratosphereand,oncethere,theymaypersistfordecades,CFCswillcontinuetoaffecttheenvironmentforsometime.
EnvironmEntal SciEncE 41
.Human Impact on the Biosphere
Allofthesegreenhousegaseshaveincreasedintheatmo-sphereasaresultofhumanactivities.Somescientiststhinkgreenhousegasescauseglobalwarming,othersbelievethatincreasedparticulateemissionsarecoolingEarth,andstillothersbelievethatthermalpollutionwillhavethebiggesteffectonglobalclimate.ScientistswhostudyglobalclimatetrendshaverecordsthatshowEarth’saveragetemperaturehasrisen0.7degreeFahrenheitto1.3degreesFahrenheitinthelast100years.Eventhoughmanyscientistsagreethatglobalwarmingmaybehappening,theydisagreeaboutthedamagethatthiswarmingmightdo.
CFCs and the Ozone LayerMany scientists agree that CFCs also destroy ozone in the stratosphere, thus thinning the ozone layer and allowing additional harmful ultraviolet radiation to reach Earth. Increased amounts of ultraviolet radiation can damage or kill plant and animal cells. All organisms on Earth are at risk from the thinning of the ozone layer.
the amounts of carbon dioxide in the atmosphere have shown a general upward trend from the 1960s to the present.
pArt
s pe
r m
iLLi
on
370
360
350
340
1957 1970 1980 2000
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Human Impact on the Biosphere.
Solutions to air PollutionTheCleanAirActof1970createdfederalairpollutionregula-tionsthateachstatemustenforce.Sincethisenactment,theUnitedStateshassignificantlyloweredthelevelsofsixmajorairpollutantsincludingsulfurdioxides,nitrogenoxides,andparticulates.
Thereareseveralwaysthatthenitrogenoxides,sulfurdioxides,andparticulatesthatpowerplantsandindustriesreleaseintotheairhavebeenlowered.Someplantsburncoalthathasalowersulfurcontent.Othersremovethesulfurfromcoalorconvertcoaltoaliquidorgasbeforeitisburned.Athirdwaytoreducegreenhousegasemissionsistousealter-nativesourcesofpower,suchaswind,water,orsolarenergy.
Anaddedbenefitofusingalternativeenergysourcesisthattheycanproduceelectricitywithoutproducingthermalpollution.Whenelectricityisproducedateitherafossilfuel–ornuclear-poweredpowerplant,morethantwo-thirdsoftheenergyinthesourcematerialisreleasedasheatandnotconvertedintoelec-tricity.Thisisamajorsourceofthermalpollutionintheworldtoday.Inaddition,muchstudyhasgoneintodesigningequip-mentsuchasfilters,separators,andscrubbersthatcanbeusedinsidesmokestacksandexhaustsystemstoremoveparticulates.
Becausecarsandtrucksproducehighlevelsofnitrogenoxides,lawsrestricttheamountofairpollutantsthatvehicles
mayemit.Adeviceknownasacatalyticconverterconvertsharmfulpollutantscreatedfromtheburningofgasolineintosafersubstances.Stateswithsmogproblemsrequirethatcarsundergoannualinspectionstotestemissionsandfueleffi-ciency.Today,99percentofcarsintheUnitedStatesburnonlyunleadedgasoline,whichhassignificantlyreducedtheamountoftoxicleadintheairintheUnitedStates.
Wet scrubber
dirty wAter
dirty gAs
cLeAn wAter
wet gAs
cLeAned gAs
a wet scrubber removes hazardous particulates and sulfur dioxide gas from power plant emissions.
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Agrowingnumberofpeoplearebuyinghybridvehicles.Hybrid vehiclesusetwodifferentsourcestoproduceenergy.Currently,mosthybridvehiclesuseasmallgasoline-poweredengineandanelectricmotorwithaspecialbattery.Hybridcarsgetsignificantlybettermileagethanmostconventionalgasoline-onlyvehicles,sotheyhelpconservefuelresources.Inaddition,theyemitonlyafractionofthesmog-producingpollutantsthatconventionalvehiclesemit.
Someautomanufacturersaredevelopingzero-emissionvehicles—vehiclesthatdonotproduceanyairpollution.Vehiclespoweredbyafuel celloperateonelectricityproducedthroughachemicalreaction.Themostcommontypeoffuelcellreliesonachemicalreactionbetweenhydrogenandoxy-gen.Theonlyby-productsofthereactionareheatandwater.
Aneasywaytoreduceairpollutionfromvehiclesistonotusethemasmuch.Youcanpracticepollution preventionbywalking,biking,orcarpooling.
Trip ChainingRemember when you trip chain, you can help save the air in addition to time. Chances are, you and your family members already combine errands, which helps cut down on traffic congestion and saves gasoline. If you can, try cycling or using public transportation whenever possible.
How much mileage would you save by going from a ➔ B ➔ c ➔ D ➔ E ➔ F ➔ a rather than from a ➔ B ➔ a ➔ c ➔ a ➔ D ➔ a ➔ E ➔ a ➔ F ➔ a?
3 miLes 1 miLe
1.75 miLes
2 miLes
2.5 miLes1.5 miLes
1 miLe
oFFice suppLy store
Bgrocery
store
Fyour Home
A
sister’s scHooL
D
LibrAry
CFriend’s House
E
2 miLes
1.25 miLes
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Human Impact on the Biosphere.
Reducingtheamountoffossilfuelsweburncanhavewide-rangingpositiveeffectsontheenvironmentincludingcleanerairandwater.Itmayalsohelpreduceacidrainandslowglobalwarming.Scientistssuggestthatusinglessfossilfuel,changingtorenewableandalternativeenergysources,protectingforestsandreplantingharvestedtrees,andslowinghumanpopulationgrowthwillallbenefittheenvironmentinthelongrun.
Water and Water PollutionPollutionmayenterabodyofwaterdirectlyorindirectlyasrunofffromapointanywhereinabodyofwater’swatershed.Awatershedistheregiondrainingintoariver,riversystem,orotherbodyofwater.Smallwatershedsmakeuplargerones.Forexample,theMississippiRiverdrainsawatershedofabout1,243,000squaremiles.Precipitationthatfallsatanypointwithinabodyofwater’swatershedwilleventuallydrainintothatbodyofwater.Manykindsofpollutantscandiminishwaterquality,includingtoxicmetals,industrialwaste,agriculturalchemicals,householdproducts,petroleumproducts,andheat.
Wind energy, the fastest growing energy source, can reduce the need for power plants that burn fossil fuels.
EnvironmEntal SciEncE 45
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FertilizersChemicalsusedtofertilizelawnsandcropsmaybecarriedbyrainwaterintolakes,streams,andotherbodiesofwater.Pollutantssuchasfertilizersandpesticidesthatenterourwatersystemfromrunoffarecallednonpoint source pollutionbecausethesourcesofthepollutioncannotbetracedtoasingleidentifi-ablepoint.Thephosphatesinfertilizersareplantnutrientsthatcropsneed,butiftheygetintopondsandlakes,theycauseovergrowths,or“blooms,”ofalgae.Thealgaecancoverthewatersurface,blockinglife-supportingsunlightandkillingsomeformsofpondlife.Whenthealgaedieanddecay,thedecayprocesstakesoxygenfromthewater,whichinturnmaykillfishandotherorganisms.
PesticidesChemicalsthatfarmers,homeowners,andothersusetocontrolpests,suchasinsects,arecalledpesticides.Somepesticideskillonlyparticularspecies,butothersaretoxictomanylivingthings.Manyofthesetoxicchemicalsendupintheair,surfacewater,andgroundwater.Pesticidesinrainwaterrunoffkillmillionsoffisheachyear.TracesofpesticidescanbefoundinnearlyallofthefreshwaterfishintheUnitedStates.
DDT in the Food ChainA pesticide called DDT was widely used in the 1950s and 1960s to kill mosquitoes and insects that harmed crops. But DDT also killed many beneficial insects and washed into bodies of water, where it was absorbed by tiny water organisms. Small invertebrates that fed on the contaminated organisms were affected next. Fish ate the contaminated invertebrates, and the fish were in turn eaten by birds. In this way, the DDT moved its way up the food chain. At each level, the pesticide became more concentrated as a result of a phenomenon known as biomagnification. DDT killed many insects, invertebrates, fish, and songbirds. The buildup of the pesticide in the bodies of larger birds, such as brown pelicans, bald eagles, and peregrine falcons, caused their eggs to develop thin, fragile shells. These thin-shelled eggs tended to break in the nest before the young were hatched, causing a rapid and drastic decline in the populations of these species. DDT’s effect on birds received wide public attention when Rachel Carson published her book Silent Spring (1962), which helped rally public support for the ban of most uses of DDT.
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toxic metals and industrial PollutantsMercury,lead,andothertoxicmetalsthatareminedorusedinindustryhavecontaminatedbodiesofwater.ThesetoxicmetalsaswellasPCBs(syntheticchlorinecompoundsonceusedinpaints,adhesives,lubricants,andelectricalequipment)arealsoexamplesofwaterbornepollutantsthatbecomemoreconcen-tratedastheymoveupthefoodchain.Manystateshaveissuedhealthwarningsbecauseofthetoxicmetalcontentofnativefish.
Household ProductsSomechemicalsusedinhouseholdproductsalsocausewaterpollution.Whenyoucleanthebathtub,forinstance,theclean-ingsolutiongoesdownthedrain.Whathappenstothewaterthen?Ifyouliveinacityorsuburbanarea,thatwastewaterispipedtoawater-treatmentplant,whereitisfilteredandtreatedsothatthepollutantscanberemovedandthewaterreused.Inruralareas,wastewatermaybepipedintoaseptictank.Eventually,waterleavestheseptictankandfiltersdownintothesoilandbackintothegroundwater.Whenthiswastewatercontainsmoretoxicchemicalsthanthesoilcanabsorb,thechemicalsalsoenterthegroundwater.
septic tAnk
HouseHoLd wAstewAter
perForAted pipe
distribution box (optionAL)
drAin FieLd
vent pipe
grAveL or crusHed
stone
nonperForAted pipemAnHoLe (For cLeAnout)
Household septic system
Household sewage may be disposed of through a septic tank and leach field. Water and wastes spread over the leach field, where the soil filters out some chemicals and decomposers break down organic matter.
Hazardous
household
products include
pesticides, paints,
solvents, drain
cleaners, oil,
gasoline, and
car batteries.
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Petroleum ProductsPetroleum(oil),gasoline,kerosene,andotherpetroleumprod-uctsareamajorsourceofwaterpollution.Youprobablyhaveheardaboutoilspillsatsea.Oilcandevastateoceanecosys-tems.Itkillssomeorganismsimmediately.Othersdiemoreslowlyasoilcoatstheirfeathers,fur,orskin.Someoilsinkstotheoceanfloor,whereitkillsbottom-livingcreatures.Evenwithexpensivecleanupefforts,ittakesthreeto10yearsformarinelifetorecoverfromtheeffectsofanoilspill.
thermal PollutionThermalwaterpollutionoccurswhenwateristakenfromarivertocoolapowerplant.Iftheheatedwaterisreleasedbackintotheriver,itraisestheriver’stemperature.Thermalpollu-tionofthewaterharmsmanyaquaticorganisms.Itmayhurtthemdirectlyorlowertheamountofdissolvedoxygeninwaterandmakeorganismsmorepronetotheeffectsofdamagingchemicalsandattacksbyparasitesordisease.
Solutions to Water PollutionSupposeyouareoutplayingbasketball.Yougetthirstyandruninsidetogetaglassofwaterfromthekitchentap.Wheredoesthattapwatercomefrom?IntheUnitedStates,mostcom-munitiesgettheirwatersupplyfromriversandlakesorfromundergroundaquifers.Beforethewatergetstoyou,itmustundergoatreatmentprocesstomakesureitmeetsthestandardsforsafe,cleandrinkingwaterthataresetbytheEnvironmentalProtectionAgency(EPA).Becausewaterissoimportanttoalllife,wemustprotectwaterresourcesandpreventandcleanupwaterpollutionwheneverpossible.
An oil spill or
the emissions
from a factory
are considered
point source
pollution because
the source of the
pollution can
be identified.
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Human Impact on the Biosphere.
When waterfowl
fall victim to oil
spills, immediate
action is often the
only thing that
will save them.
Specially trained
and licensed
wildlife rescue
crews “shampoo”
individual birds
to remove the
oil from their
feathers. They
also give the birds
food, medical
care, and a warm
place to stay
until it is safe to
release them
back into the
wild. Such rescue
efforts, however,
can be very
labor-intensive
and costly.
Methods of Oil-Spill Cleanup Here are some of the ways oil spills can be cleaned up.
• Bioremediation uses fertilizers to increase the population of oil-eating microbes. This process is very harmful to humans and animals in the first 24 hours after application. If animals cannot be restricted from the cleanup area, bioremediation should not be used.
• Booms are floating barriers used to contain and absorb oil spills. Their high-maintenance requirements can sometimes outweigh their effectiveness.
• Burning reduces large amounts of oil to a tarry residue. It requires favorable weather conditions and must be done within 72 hours after the spill occurs. Unfortunately, burning produces smoke that is poisonous to humans and animals.
• Chemical dispersants help scatter oil into larger volumes of water and help prevent oil from reaching shorelines. Dispersants must be mixed with oil, which requires good wave action.
• Hot-water washing works best on heavily oiled beaches, but hot water “cooks” all plant and animal life in its path, leaving beaches sterile.
• Skimmers collect oil from the water’s surface. Under the right conditions, skimmers serve as one of the most environmentally sound forms of oil collection. However, like booms, skimmers are difficult to maintain.
• Oil-absorbing products and chemicals soak up oil. When they are removed from the area, the oil is removed with them. These products are often used to clean up oil on land but have also proved effective for oil spills in water.
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reducing Water PollutionTherearemanywaystoreducewaterpollution.Farmerscankeepfertilizeroutofrunoffbyusingonlysmallamountsatatimeorbyswitchingtofarmingpracticesthatrequirelessfertilizer.Theycancuttheiruseofpesticidesorswitchtobiologicalcontrols.Forexample,theymightusenaturalpredators,suchasladybugs,toeatinsectpests.
TherehavebeenimprovementsinwaterqualityintheUnitedStatesthankstotheCleanWaterAct.Forexample,itisagainstthelawtodischargeanytoxicpollutantsintosurfacewaters.Inaddition,moststateshavenowpassedlawsthatrequirepowerplantsandotherfactoriestocoolwaterbeforereleasingitbackintoriversandstreams.Eventhoughsomesourcesofwaterpollutionhavebeenaddressed,muchmorecanbedone.
Protecting Water resourcesOnewaytoprotectwaterresourcesisthroughconservation.Wecanconservewaterbycut-tingtheamountweusedaily.Somescientistsestimatethatabout60percentofthewaterpeopleuseiswastedthroughleaks,evaporation,andotherlossesthatcouldbeprevented.Forexample,theaverageleakyfaucetcanwasteasmuchas2,000gallonsofwaterayear—that’senoughwatertofill40bathtubs!
Industriesandfarmsalsowastewater.Waterusedincropirrigationisoftennotusedefficiently.Forexample,irrigatingcropsintheheatofthedayiswastefulbecauseasignificantamountofwaterevaporatesbeforeplantrootscantakeitup.
Tosavewater,everyoneneedstouselessinhisorherdailylife.Installinglow-flowshowerheadsandtoiletsandfixingleakypipesandfaucetsarefewwaysyoucanconservewater.Farmersareswitchingtodrip-irrigationsystems,inwhichtubesdeliverwaterdirectlytoplantroots.Gardenerswholiveinaridclimatesmightconsidergrowingnativeplantsthatareadaptedtodryconditions.
Currently,
40 percent of
the world’s people
live with serious
water shortages.
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land Degradation and PollutionIfyoulookcloselyatashovelfulofsoil,youwillnoticethatthereisalotmoretoitthanyoumighthavethought.Soilcontainserodedrock,organicmatter,water,air,minerals,nutrients,andorganismssuchasearthwormsandotherkindsofdecomposers.
SoilSoilhaslayers.Thetoplayer,orlitterlayer,consistsofleaves,twigs,fungi,animalwastes,andpartiallydecomposedorganicmaterials.Thelitterlayeristhinandusuallydarkbrownorblack.
Thenextlayer—themostfertile—iscalledtopsoil.Thedepthandfertilityoftopsoilarefactorsthatdeterminewhatkindsofplantscangrowinaparticularenvironment.Topsoilcontainsmostoftherootsofplantsandmostofthesoil’sorganicmatterandisthestorehouseforwaterthatplantsneedtogrow.Decomposers,suchasmushroomsandotherfungi,intopsoilmakenutrientsavailabletoplants.
oAk tree
wood sorreL
eArtHworm
moLeLeAF Litter
topsoiL
subsoiL
root system
red eArtH mite springtAiL bActeriA
Fungus
Actinomycetes
nemAtode
pseudoscorpion
Honey Fungus
miLLipede
Fern
bedrock
Soil layers
in most soils, the layers include the litter layer, topsoil, subsoil, and bedrock.
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Underneaththelitterlayerandtopsoilisthesubsoil.Thislayerconsistsofbroken-downrockmaterialsincludingsand,silt,clay,andgravel.Thislayerdoesnotcontainanynutrientsororganismsthatcansupportplantgrowth.Belowthesubsoilisbedrock,theunweatheredrockthatwasbrokendowntomakethesoil.
Soil ErosionSoilerosionisanaturalprocess.Windwearsdownmountains.Sediments,carriedinrivers,buildupdeltas.Wind,water,andiceallcontributetonaturalsoilerosion.However,thelitterandtopsoillayersofsoilhelppreventerosionbecausetheycontainplantrootsandairspacesthatabsorbwater.Whenplowingdigsuprootsorloggingremovestreesfromthesoil,topsoilbecomesexposedtothenaturalforcesoferosion.Whentopsoilislost,thesoilbeneathitisoftenlessfertileandunabletoabsorbwater.Farming,logging,mining,construction,overgraz-ingbylivestock,andburningforestsalldestroythesoilplantcoverandspeeduperosion.Today,soiliserodingfasterthanitformsonaboutone-thirdofEarth’scroplands.
Signs of erosion and land degradation include the following:
• Mud and silt on sidewalks and driveways after a rain
• Exposed tree roots where the soil has been washed away
• Roadside ditches filled with sediment
• Muddy water in a stream or river
• Caved-in stream banks
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land PollutionPaperandplasticbags,aluminumcans,glassbottles,orangepeels,eggshells,oldtires,oldhomeworkassignments,andworn-outclothingarejustsomeofthetrash,orsolid waste,thatpeoplethrowawayeveryday.GarbagetrucksacrosstheUnitedStatescollect132milliontonsofsolidwasteeveryyear.
Mostsolidwastesaredumpedinsanitarylandfillsandthencoveredwithalayerofsoil.Wastessuchasgrassclippingsandspoiledfoodarebiodegradable,thatis,theywereonceliv-ingorganisms,sonaturalprocessescanbreakthemdown.Wastessuchasplasticsorglassbottlesarenonbiodegradable—naturalprocessescannotbreakthemdown.Nonbiodegradablewastesmaylastforhundredsorthousandsofyears.Sometimes,evenbiodegradablewastesinlandfillsdonotdecaybecausetheoxygenthatmostdecomposersneedtobeginthedecayprocessdoesnotreachtheburiedtrash.
Hazardous WastesYoumightthinkthegarbagethathouseholdsandbusinessesthrowoutmakesupthelargestpercentageofsolidwaste,butmorethan98percentofsolidwasteactuallycomesfromindustriessuchasmining,agriculture,andoilandnaturalgasproduction.Thesolidwasteproducedbyminingandmanyindustriescanpollutetheair,water,andsoil.Somesolidwastesarehazardousbecausetheycontaintoxiccompoundsorreleasetoxicfumes.
Sometimes,hazardouswastesareburiedinmetalcontain-ers.Improperlycontained,toxicsubstancescancorrodethroughthemetalandseepintothesoil,eventuallycontaminatinggroundwater.MuchofthegroundwaterintheUnitedStateshasbeencontaminatedwithagriculturalorindustrialchemicals,orwithoilandotherpetroleumproductsthathaveseepedintothesoilandthenintothegroundwater.Thesewastesmaybetoxictobothanimalsandplants.
Currently in the United States, about 55 percent of solid waste goes into landfills; about 30 percent is recycled; and about 15 percent is incinerated, or burned.
Each year,
American office
workers discard
about 4 million
tons of paper.
That’s enough to
build a 12-foot
wall from New
York City to
Los Angeles.
Hazardous
wastes are any
solid wastes that
contain toxic
compounds, are
unstable, catch
fire easily, or
corrode metals.
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WithfundingfromthefederalSuperfundprogram,theEnvironmentalProtectionAgencyisinvestigatingandcleaningupmorethan85,000hazardouswastesitesacrossthecountry.
Anabandonedpieceofcommercialorindustriallandthatiscontaminated(orissuspectedofbeingcontaminated)byahazardoussubstanceisknownasabrownfield.Abandonedfactoriesandgasstationsareexamplesofbrownfieldsites.Arealorperceivedhealthdangermakesitmorecomplicatedtoredevelopthesitefornewuses.Anewlaw,however,allowscommunitiesanddeveloperstoreclaimbrownfieldsbyworkingwiththeEPAtocleanupthesites.TheEPAdetermineshowmuchcleanupneedstobedonetomakethesitesafeforitsnewuse.Cleaned-upbrownfieldshavebeenredevelopedforofficesandstores.Somehaveevenbeenturnedintoparkswithbikepathsandplaygrounds.
Solutions to land Degradation and PollutionLossoftopsoilisoneofthemostseriouslanddegradationproblemstoday.MostofthetopsoilthaterodesintheUnitedStatescomesfromlandusedtoraisecropsorgrazecattle.AccordingtotheNaturalResourcesConservationServiceoftheU.S.DepartmentofAgriculture,morethan5billiontonsofsoilerodefrompasture,rangeland,andcroplandintheUnitedStateseveryyear.Nearlyfivetimesasmuchsoilerodesfromcultivatedcroplandasfromuncultivatedland.
If you take used
motor oil to an oil
recycling center,
it can be cleaned
and reused, which
saves energy.
Recycled oil
can be used
to generate
electricity for
homes and
businesses.
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Human Impact on the Biosphere.
Soil conservationFarmersaroundtheworldhavelearnedtouseavarietyofmethodstoconservesoilandpreventsoilerosionontheirfields.Inthepast,bare,newlyplowedsoilwasoftenleftexposedtowindsandrainformonthsatatime.Morerecentfarmingpractices,however,recommendthatfarmersleaveaplantcoveronthesoilatalltimes.Inno-tillfarming,specialmachinespokeholesthroughthelayeroforganicmatterleftoverfromthepreviouscropandplantnewseedsintotheunplowedsoil.Otherkindsofsustainablefarmingpracticesreducetheneedforfertilizersandpesticidesandalsoimprovethesoil’sabilitytoholdwater.
Farmersinveryhillyormountainousareasconservesoilwithterracing.Terracingcreateslevelfieldsalongtheslopeofahill,preventingsoilerosionandholdingwaterforthecrops.Onmoregentlyslopinglands,farmersconservesoilbycontourfarming.Theyplantcropsinrowsthatgoacrosstheslopedlandratherthanupanddown.Instrip-cropping,farmersplantdiffer-entcropsinstripsthatalternate.Sometimestheyplantcropsthataregrownasfeedforlivestockbetweenrowsoftrees.
terracing (left) and contour strip-cropping are soil conservation practices that farmers use to help prevent soil erosion on fields.
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Streambankscanbeprotectedagainsterosionbyusingplants,rocks,orstructuralmeasures.Inwoodlands,planting,thinning,pruning,andproperharvesttechniquescanhelppro-tectthesoilandclimate,maintainbeauty,improveconditionsforwildlife,andmaintaincoverforerosioncontrol.
reduce, reuse, recycleThethreeR’s—reduce,reuse,andrecycle—canbeappliedtodecreasetheamountofsolidwastethathumanactivitiesgenerate.
rEDUcEToreducetheamountofsolidwasteyouthrowout,simplydonotbringhomethosematerialsinthefirstplace.Buyloosefruitsandvegetablesratherthanproducepackagedinaplastic-wrappedfoamtray.Chooseitemsthatdonotuseexcesspackagingmaterials.
Toreducetheamountoforganicmatterthatyouthrowaway,putkitchenscrapsandgrassclippingsintoacompostpile.Overtime,thematerialwilldecomposeandbecomeanutrient-rich,organicfertilizer.
Weallcanchangeourhabitstoproducelesswastejustbybeingmindfulofthethingswebuy.Industries,businesses,andgovernmentagencieshaveallbeguntochangethewaytheybuysuppliesanddisposeofwastes.Reducingwastesavesmoneyandhelpstheenvironment.
Using compost to help control erosion is a new technology being implemented in the United States.
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Human Impact on the Biosphere.
rEUSEEverytimeyouturnapieceofpaperovertowriteonthebackinsteadofusinganewpiece,youarereusingaresource.Ifyoubringfoodhomeinplasticbags,youcanreusethebagstocarryyourgymclothes.Ifyouuseapapercuptogetadrink,youcanreuseittoplantseedsforyourgarden.Plasticandglassbottlesandcontainersthatheldfoodcanbewashedandreusedoverandover.
Industriesandbusinessesalsoreusematerials.Somestoresselldrinkingwaterinreusableplasticjugs.Manyhotelsandmotelsoffergueststheoptiontonothavetheirsheetsandtowelswashedeveryday,whichsaveswaterandenergy.
rEcyclEPaper,plastics,glass,andaluminumcanberecycled—collectedandusedtomakenewproducts.Newspaperscanberecycledintonewnewspaper.Glasscanbecrushed,melted,andmoldedintootherglassitems.Aluminumcanbemeltedandformedintonewcans.Plasticscanbebrokenup,melted,andreformedintonewplasticproducts.Theserecyclingpro-cessesconserveourresourcesandreducewasteinlandfills.
About 65
percent of all
the aluminum
beverage cans
sold in the
United States
are recycled. It
takes the same
amount of energy
to make one can
from aluminum
ore as it does to
make 20 cans
from recycled
aluminum.
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.Human Impact on the Biosphere
Because paper
products are
made from trees,
you help reduce
the number of
trees that need to
be cut when you
recycle paper. In
the United States,
about 40 percent
of all used paper
is recovered
and recycled.
Mexico, Thailand,
Denmark, South
Korea, and Taiwan
all recycle at least
70 percent of their
waste paper. The Problem With PlasticsMost plastics are made from petroleum and are nonbiodegradable. Plastic items make up about 20 percent of all municipal solid waste. Plastics are more difficult to recycle because there are so many different types, and they must be separated according to type. Currently, it is cheaper to make new plastics from petroleum than to recycle most plastics. In addition, recycling often uses more energy than making new plastics. Therefore reusing plastic containers or, better yet, purchasing fewer plastic items reduces the amount of plastics in landfills more efficiently than recycling them.
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Human Impact on the Biosphere.
three species that have become extinct are (1) the giant ground sloth, (2) the hairy mammoth, and (3) indricotherium, the largest land mammal that ever lived.
1 2 3
Hazardous WastesBecauseofthedangershazardouswastesposetotheenviron-mentandthedifficultiesassociatedwiththeirdisposal,reduc-ingtheproductionofhazardouswastesisthemostdesirablegoal.Variouslocal,state,andfederallawsregulatethedisposalofhazardouswastes.
Somehazardouswastescanbetreatedtoremovethetoxicmaterialswithbiologicalcontrolssuchasbioremediation.Whenbioremediationprocessesareused,organismssuchasplantsandbacteriadestroyhazardouswastesormakethemharmless.Bioremediationissometimesusedtohelpcleanupoilspillsandtocleanupstreamsandgroundwatercontami-natedwithhazardouswaste.
Endangered and threatened SpeciesDuringEarth’shistory,manyspecieshavebecomeextinct,thatis,alltheindividualsofagivenspecieshavedied,andthespecieshasdisappearedfromEarth.Scientistsestimatethat99percentofallspeciesthathaveeverlivedonEartharenowextinct.Somespecies,suchasthegiantgroundsloth,diedoutgraduallyastheenvironmentchangedandthespecieswasunabletoadapttothenewconditions.Others,suchastheCarolinaparakeet,havebecomeextinctbecauseofhumanactivities.
.Human Impact on the Biosphere
Aspeciesthathassofewindividualsleftthatitisindan-gerofextinctioniscalledanendangered species.Someendan-geredspeciesincludethegiantpandaofChina(only1,600leftinthewild),theblackrhinocerosofAfrica(3,100remain),andthewhoopingcraneofNorthAmerica(fewerthan500areleft).About500species,bothplantandanimal,areendangeredintheUnitedStates.
The Last Passenger PigeonIn 1810, an ornithologist (a scientist who studies birds) named Alexander Wilson saw a flock of passenger pigeons one mile wide and 240 miles long. He estimated that the flock was composed of more than 2 billion birds. Over the next 100 years, settlers destroyed much of the pigeons’ forest habitat when they cut down trees to make farms and home sites. Hunters killed millions of the birds for food. The last passenger pigeon in existence died in 1914 in a zoo in Cincinnati, Ohio.
in recent years, thanks to efforts by wildlife workers, the whooping crane population has enjoyed some growth.
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Threatened speciesarespeciesthatarelosingmembersatsucharatethattheywillbecomeendangeredifnothingisdonetochangethesituation.Africanelephantsareanexampleofathreatenedspecies.Eventhoughtheremaystillbe500,000elephantsinthewild,thisnumberisdownfromthe3to5millionofthe1930s.IfpeoplecontinuetoillegallyhuntAfricanelephantsfortheirivorytusks,theelephantsmaybecomeendangered.
causes of ExtinctionManyscientistsbelievethatthefossilrecordindicatesthatmanyspecieshavearisen,dominatedlandorsea,andthenbecomeextinct.TheybelievethatseveraltimesduringEarth’shistory,therehavebeenmassextinctionsinwhichsomecatastrophewipedoutmostofthethen-existingspecies.Duringonesuchepisode,scientistssay,thedinosaursdied.Scientistsbelievethatanoutsideevent,suchastheimpactofahugeasteroid,causedmostmassextinctionsbychangingEarth’sclimate.
OnEarthtoday,however,extinctionsarehappeningatanalarmingrateasaresultofhumanactivities.Scientistsestimate50to200speciesbecomeextinctdaily.Humansareseverelydamagingsomeofourcriticalecosystems,suchastropicalrainforestsandcoralreefs.Unfortunately,thesetwoecosystemshavethegreatestbiodiversityofanyecosystemsonEarth.
many species of manatee are endangered or threatened.
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.Human Impact on the Biosphere
Threats to BiodiversityThe World Wildlife Fund has identified five key threats that contribute to decreases in biodiversity and increases in threatened and endangered species.
Habitat loss. The clearing of forests, prairies, and other wild lands for home building, farming, and other con-struction forces animal species that once lived in these places to move deeper into the remaining natural areas. With limited habitat remaining, significant population declines occur that threaten species’ survival.
introduced species. Introduced species are plant or animal species that are not native to a particular area. Introduced species compete with native species for nutrients, water, and space and may crowd out the native species. For example, during the 1930s farmers in the southeastern United States planted kudzu, a vine native to Asia, to control erosion. The kudzu vines choked out native plants and were so difficult to control they soon covered telephone poles and abandoned buildings.
Pollution. Pollution can damage an ecosystem and harm organisms. For example, an oil spill near a coastal area may wipe out entire populations of plants and animals in the affected area.
Population growth. Each year more than 90 million people are born, placing increasing strain on the natural resources that all life on Earth rely upon.
overconsumption. Overconsumption refers to using up natural resources faster than they can be replenished. For example, if we use forest products such as paper faster than the forests can regrow, forest habitat that is critical for the survival of many species of plants and animals is lost.
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Human Impact on the Biosphere.
Extinction SolutionsLawsarenowinplacetopreserveandmanageendangeredspecies’naturalhabitat.Recoveryprogramsalsohavebeendevelopedtocapturesomeoftheindividuals,helpthemreproduceincaptivity,andthenputthembackintoasuitablehabitat.Thisapproachisoftenusedwhenthereareonlyafewindividualsofanendangeredspeciesremaining.SuchprogramshavesavedanimalssuchastheAmericanalligatorandtheCaliforniacondor.
Inaddition,legallyprotectedwildernessareasthatpre-serveentireecosystemshavebeensetaside.National,state,andinternationalparksandwildliferefugeshavebeenestab-lishedtoprotectwildlife.IntheUnitedStates,theNationalWildlifeRefugesystemincludesmorethan500protectedeco-systems.Mostoftheserefugesarewetlandsthataremanagedtoprotectmigratorywaterfowl,buteveryotherorganismintheseecosystemsbenefitsfromprotectionaswell.Evenso,protectedwildlifesanctuariesmakeuponly6percentofthelandareaworldwide.Regulatedwildlifemanagementprogramsprotectspecieswherehuntingisallowed.Theymakesurepopulationsofwildanimalsarenotoverhunted.
peregrine FALcon
bLAck-Footed Ferret
the dodo was a flightless bird that lived only on the island of mauritius, near madagascar. it was abundant there when sailors first arrived in the 1400s. the dodo was hunted for its meat and became extinct in 1680, less than 200 years after sailors first saw it.
Endangered species in the United States that are being bred in captivity and released to the wild include the peregrine falcon and black-footed ferret.
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.Human Impact on the Biosphere
The Convention on International Trade in Endangered Species (CITES) is an agreement that went into effect in 1975. CITES bans commercial international trade of endangered species and regulates trade of other species that might become endangered. Some 28,000 species of plants and 5,000 species of animals are protected by CITES. More than 160 countries uphold this agreement.
assessing Environmental impactsNowthatyouhaveseenhowhumanactivitiesaffectthebiosphere,youcanbegintounderstandhowharditistopre-dictalltheenvironmentaleffectsofanyconstructionproject.Whatmightseemlikeasimpleproject—buildinganewhouse,forexample—mayhavemanyenvironmentalimpactsbeyondsimplydisturbingthesoilon-site.Whathappenstothemolesandshrewsthatliveinthesoil?Whathappenstotheredfoxandthegreathornedowlthatpreyuponthemolesandshrews?Howwillsoilerosionfromthesitebecontrolled?Willthetop-soilbesavedandputbackafterconstruction?
Environmental impact StatementsWhenafederalagencyproposesnewregulationsoractionsthatmayaffecttheenvironment,itisrequiredbylawtoprepareanenvironmentalassessment(EA)oranenvironmentalimpactstatement(EIS).Federal,state,andlocalagenciesandthegen-eralpublicmayreviewtheproposedactivitybeforeitbegins.AnEIS,whichmaybeaslongas1,000pages,mustdiscussfiveenvironmentalconcerns:
• Theenvironmentalimpactoftheproposedaction
• Anyharmfulenvironmentaleffectsthatcannotbeavoided
• Alternativestotheproposedaction
• Short-termuseoftheenvironmentversusmaintainingandenhancingtheenvironment’slong-termproductivity
• Anypermanentcommitmentofresources
Taking Action.
TakingActionNowthatyouhavecompletedmostoftherequirementsfortheEnvironmentalSciencemeritbadge,thinkaboutwhatyouhavelearned.Howareorganismsandtheirenvironmentsconnectedinyourcommunity?Whataresomesourcesofairandwaterpollu-tioninyourcommunity?Whataresomewaysyoucanpreventpollutionandconserveresourcesathomeandatschool?
think Globally, act locallyAsaBoyScout,youareexpectedtoleaveyourcampsitecleanerthanyoufoundit.Wouldn’titbegreatifeveryoneonEarthfeltthesamewayaboutprotectingtheenvironment?
Sometimesitmayseemthatenvironmentalproblemsaretoobigforanyonepersontosolve.Butifeachpersonstartsdoingthingsthatwillhelptheenvironment,itcanmakeahugedifference.Themorepeoplebecomeinvolvedinpreventingpollutionandconservingresources,thebetteritwillbefortheenvironment.
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.Taking Action
Ten Ways to Reduce Pollution• Walk, bike, or
arrange to carpool with friends to cut down on air pollution.
• Pack your lunch in reusable containers instead of using foil or plastic wrap. Carry your lunch in a reusable nylon bag or lunch box instead of using a new paper bag each day.
• Use rechargeable batteries. Recycling programs for disposable alkaline are not widely available, so batteries end up as solid waste in landfills.
• Use environmentally friendly cleaning solutions such as baking soda and vinegar instead of chemical cleaning products.
• Recycle used clothing and household items by having a garage sale or taking them to resale shops.
• Volunteer to pick up trash in a park, at a beach, or along a river.
• Encourage your family to buy locally grown fruits and vegetables. Since locally grown food does not have to travel great distances, fewer greenhouse gases and other pollutants are emitted as the produce is transported from field to market.
• If you live in a house with a yard, suggest that your family not use chemical fertilizers on the lawn. Pull weeds by hand instead of using chemical weed killers.
• Use a rake instead of a leaf blower. Gas-powered leaf blowers produce as much air pollution as some cars.
• Keep organic matter out of landfills by making compost. Place leaves, grass clippings, raw kitchen scraps, and other plant material in a pile or a bin. Keep the pile moist and mix it regularly. Over a period of about six months, the material will break down and can be used in the garden as a replacement for chemical fertilizers.
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Taking Action.
Ten Ways to Conserve Resources• Turn off lights, fans,
radios, and televisions when leaving a room—even if you are going to be gone only a few minutes.
• Shut off the faucet when you are brushing your teeth or washing your face.
• Reduce, reuse, and recycle paper products, glass, aluminum, steel, and plastic items.
• Save water and energy by running the dishwasher and the washing machine only when they are full.
• If you wash dishes by hand, rinse them in a sink or dishpan of water rather than under running water.
• Ask your family’s permission to lower the thermostat. If each American household were to lower its average heating temperature by 6 degrees over a 24-hour period each day, the equivalent of 500,000 barrels of oil would be saved.
• Suggest that your family eat fewer meals that include meat. The production and processing of grains requires far less water and land than does meat.
• If you notice leaky faucets or pipes, ask if you can help fix them.
• Ask your parents about installing water-saving showerheads in your home if you don’t already have them.
• Have your family consider replacing incandescent lightbulbs with compact fluorescent lightbulbs. CFLs use 75 percent less energy and last 10 to 13 times longer than standard bulbs.
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Oneveryimportantthingyoucandothatwillhavelong-rangebenefitsfortheenvironmentisplanttrees.Plantingtreeshelpsconserveforestresourcesandprovidehabitatforwildlife.Plantingtreesalsohelpscounterairpollution.Likeallplants,treestakeincarbondioxideforpho-tosynthesis.Moretreesmeanslesscarbondioxideenterstheatmosphere.Contactalocalconservationgroupandfindoutifyourtroopcouldhelpwithtreeplantingsinanaturalareathatisbeingrestored.Oraskpermissiontoplanttreesatyourschooloratalocalpark.Youmightevenorganizeaclassorschoolfund-raisertoprotecttropicalrainforestsinCentralandSouthAmerica.Doingpositivethingslikethesemakesyouanenvironmentalactivist.
Environmental activismSupposeyouorganizedyourtrooptocleanupalocalcreekorplant100trees?Youcanmakeadifference.
Howmuchofanimpactwouldyoumake?Everytimeonepersonstartsanenvironmentalproject,talksaboutit,advertisesit,andthencompletesit,otherpeoplenotice.Theyfigurethatifyoucandoit,socanthey.Thisishowanenvironmentalmovementbegins.
Even though
laws restrict
pollution, there
are not enough
law enforcement
officers to watch
every potential
polluter. That
is why private
citizens, like you,
must help protect
the environment.
After all, it is the
air you breathe,
the water you
drink, and the
land you inhabit.
the outdoor code As an American, I will do my best to— Be clean in my outdoor manners. Be careful with fire. Be considerate in the outdoors. Be conservation-minded.
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Careers in Environmental Science.
CareersinEnvironmentalScienceThinkingaboutacareerinenvironmentalscience?Environ-mentalscienceisthestudyofhowhumansandalllivingthingsinteractwithoneanotherandwiththenonlivingenvironment,sojustabouteveryscientificfieldinvolvesenvironmentalscience.
Tohaveacareerinscience,youmustgotocollegeandearnatleastanassociate’sdegreeforatechnicalposition,abachelor’sdegreeforaprofessionalposition,andamaster’sdegreeordoctoratedegreeforaresearchorteachingposition.Toworkinenvironmentalscience,youmaywanttoexploreacareerinthenaturalsciences,physicalsciences,orengineering.
occupations you might chooseCompaniesandagenciesworkinginthefieldsofenvironmentalscienceorconser-vationhireemployeesforagreatvarietyofoccupations.GovernmentagenciesfromtheU.S.ArmyCorpsofEngineerstotheEnvironmentalProtectionAgencyhirescientistsandmanagerstowriteandreviewenvironmentalimpactstatements.Scientistsandengineersworkingovernmentandindustrylaboratoriestodevelopwind,solar,geothermal,andotheralternativefuelstoreduceourneedforfossilfuels.Environmentallawyershelpcompaniesfollowenvironmentallaws.Environmentalengineersdesignprojectsthatareenviron-mentallysound.
.Careers in Environmental Science
Manufacturershirechemists,engineers,physicists,mathema-ticians,planners,andmanagerstodevelopmoreefficientmanu-facturingtechnologies,newenvironmentallysafeproducts,andtechnologiestoreduce,reuse,andrecyclewasteproducts.Othercompaniesemploypeopletoproperlytransportanddisposeofmunicipal,agricultural,andindustrialwastes.
Scientistsworkinginecology,toxicology,physiology,meteorology,geology,andmanyothersciencesdevelopproductsthataremoreenvironmentallyfriendly.Theyalsoresearchtheenvironmentalimpactsofhumanactivities.
Farmers,agronomists,entomologists,geneticists,water-resourcemanagers,soilscientists,foresters,wildlifemanagers,andrangemanagershelpconservewildlife,soil,andwaterresourcesthroughimprovedfarmingtechniquesandmanage-mentofwildliferesources.Theyalsohelpreducetheenviron-mentalhazardsofpesticidesbydevelopingandtestingpest-controltechniques.
Oceanographers,fisherybiologists,andfisherymanagersworkondevelopingwaystomaintainfishstocksandavoidoverfishingandwaterpollution.Wildlifemanagers,zoologists,gamemanagers,andnaturalistsworktopreservewildlifepopu-lations,breedendangeredspecies,protectnaturalhabitats,andreintroducerecoveringspeciesintothewild.
Landscapearchitects,land-useplanners,anddevelopersworktobalancetheneedsofever-growingurbanandsuburbanpopulationswiththeneedforwildernessandnaturalrecreationalareas.Teachers,writers,illustrators,televisionreporters,journalists,andmanyotherswhopromoteenvironmentaleducationalsoareenvironmentalists.
Being an EnvironmentalistEvenifyoudonotchooseacareerasanenvironmentalscientist,youcanandshouldbeaconservationistandenvironmentalistinyourownlifeandinanycareeryoupursue.Youcanbringanenvironmentalawarenesstothechoicesyoumakeeverydayasacitizen,anemployee,andacon-sumer.Youcanchoosetheenvironmentallyfriendlyoptionwhenshopping,usingresources,anddisposingofwastes.
Nomatterwhatvocationyouchoose,remembertoleave“yourcampsite”—ourplanetEarth—cleanerthanitwaswhenyouarrived.
The USDA Forest
Service maintains
the world’s
largest natural
science research
organization.
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ActivitiesinEnvironmentalScienceTheseactivitieswillhelpyoufulfillrequirementsforearningtheEnvironmentalSciencemeritbadge.
How Does the Environment affect living things?Youhavelearnedthatthenonlivingpartsoftheenvironmenthaveimportanteffectsonlivingthings.Inthisexperimentyouwilllearnhowlightaffectsearthworms.
ProcEDUrEStep 1—Cuttheshoeboxlidinhalf.Puthalfofthelidontheshoeboxsothatitshadesonesideofthebox.
Step 2—Placealampnexttothemiddleoftheshoebox,closeenoughthatitshinesontheuncoveredpartofthebox.
Step 3—Place10earthwormsonthecenterlineofthebottomoftheboxsothatthewormsarehalfinthedarkandhalfinthelight.
Step 4—Observethewormsforfiveminutes.Notetheirbehaviorinyournotebook.
Step 5—Whenyourexperimentisover,takethewormsoutsideandreturnthemtothesoil.
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oBSErvationS
1.Whatdidthewormsdoatthebeginningoftheexperiment?
2.Howmuchtimedidthewormsspendinthelightedpartofthebox?Intheshadedpartofthebox?
3.Whatnonlivingenvironmentalfactordoesthelamprepresent?
conclUSionSAnorganism’sresponsetolightiscalledphototropism.Anorganismthatrespondstolightbymovingtowarditissaidtobepositivelyphototropic.Anorganismthatmovesawayfromlightisnegativelyphototropic.Whichtypeofresponsedidyourwormsshow?Whywouldearthwormsreactthiswaytolight?
an Ecosystem StudyEveryecosysteminvolvescomplicatedinteractionsbetweentheenvironmentandtheorganismsthatlivethere.Youhavelearnedaboutsomeoftheseinteractions.Inthisprojectyouwillusethisknowledgetostudyanecosystem.
Locateabeach,pond,lake,forest,meadow,undevelopedland,orothernaturalareaoutdoors.Choosetwooutdoorstudyareasthataredifferentfromoneanother.Forexample,aforestandagrassymeadow,orasandybeachandscrubwoodland,oradesertandawetland.
canada goose
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Onceyouhaveselectedyourstudyareas,visitthesitesandwriteyourgeneralobservationsinyournotebook.Recordthetypesofecosystems,theweather,soiltypes,dominantspe-cies,andtheseason.
Aftermakinggeneralobservationsaboutyourstudyareas,selectONEofthefollowingtwoprojectstocompleterequire-ment4.Beforeyoubeginyourecosystemstudy,getpermissionfromthelandowner.Tellyourparentorcounselorthelocationofyourstudyareaandwhenyouaregoingtovisitit.Considergoingwithabuddy.
Study Plots activity
ProcEDUrEStep 1—Inyourchosenstudyareas,identifytheecosystemtypes.
Step 2—Beginatoneofthetwoecosystemsyouhaveselected.Usingayardstick,stakes,hammer,andapieceofstring,markoutashape,suchasasquare,thatcontains4squareyardsinsideitsboundaries.Thisisstudyplot1.
Step 3—Sitbesideplot1.Beginyourstudybywritinginyournotebookinformationaboutallthenonlivingfactorsaroundyou.Notethedate,timeofday,temperature,andwhetheritissunnyorcloudy,windyorcalm,rainyordry.Ifanyofthesefactorschangeasyouobservetheplot,makenoteofthechange.Notealsowhethertheplotisflatoronaslope.
Step 4—Next,lookatthelivingthingsintheplot.Ifyoucanseeanynonplantspecies(fungi,insects,birds,etc.),notetheircommonnamesordrawpicturesinyournotebookforlateridentification.Identifyallthedifferentplantsyousee.Useafieldguidetoidentifyeachspeciesbyname,ormakeadrawingofeachinyournotebook.Useamagnifyingglass,ifneeded,toseethefeaturesofeachplantandnonplantspecies.
Step 5—Estimatehowmuchspaceeachplantspeciesoccupiesintheplot.Forexample,inagrassymeadow,onespeciesofgrassmightoccupyabout90percent(nine-tenths)ofthespaceintheplot.Recordthisestimatenexttothenameofeachspeciesinyournotebook.
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Step 6—Usingayardstick,measuretheheightrangeofidenti-fiedplantspeciesandaddthedatatoyournotes.Usethesemeasurementstodrawasideviewofyourstudyplot.Trytodrawtheplantstoscale.(Seetheillustrationshownhere.)
Step 7—Gotothesecondecosystem.Repeatsteps1through6forplot2.
oBSErvationS
1.Howmanynonplantspeciesdidyouidentifyineachstudyplot?Howmanyplantspecies?
2.Whatwasthedifferencebetweenthenumberofnonplantandplantspeciesinthestudyplots?
3.Whichplotwasmorebiodiverse?
4.What,ifany,speciesdidyoufindinbothplots?
nature Study activityInthisactivity,youwillmakethreevisitstoeachofthetwostudyareas,stayingforatleast20minuteseachtimetoobservethelivingandnonlivingpartsoftheecosystem.Yourresultswillvarydependinguponwhenyouchoosetoobservethearea.Yourvisitsmustbespreadoutenoughthatyourobserva-tionsshowdifferencesbetweenyourvisits.
Side view of a study plot
stAke string
pLAnt 1 36 incHes
pLAnt 3 24 incHes pLAnt 5
24 incHes
pLAnt 2 8 incHes
pLAnt 4 4 incHes
pLAnt 6 12 incHes
ground LeveL
.Activities in Environmental Science
ProcEDUrEStep 1—Decideonyourscheduleforvisitingeachofthestudyareas.Makesureyourparentorcounseloragreeswithyourplan.
Step 2—Onyourfirstvisit,arrivequietly,makingaslittlenoiseaspossible.Findagoodplacetoobservewildlife.Makeyourselfcomfortableandhaveyournotebookandpenorpencilhandy.Notethedate,timeofday,temperature,andotherinfor-mationsuchaswhetheritiswindy,calm,sunny,cloudy,rainy,ordry.Notewhetheryourstudyareaisflatoronaslope.Drawasmallmapoftheareainyournotebook,showinghowitlooksfromwhereyouaresitting.
Step 3—Onceyouaresettledandhavenotedtheenvironmen-talconditions,beginyourobservationperiod.Identifyanyplantsyousee(byusingfieldguidesorbydrawingtheminyournotebookforlateridentification).Notethestageoflifecycleforeachplantspecies—thatis,lookforbuds,leaves,flowers,seeds,andsoon.Recordthesedatainyournotebook.
Step 4—Eachtimeyouseeanotherspecies,writedownitscommonnameanddescribeitsappearanceorbehavior.Ifyoudonotknowitscommonname,makeadrawingofitandnoteitssizeandcolorsothatyoucanidentifyitlater.Ifyouhaveacamera(onethattakesphotographsquietly!),youmaytakephotographs.
Step 5—Noteanddescribeanysoundsyouhear.Ifyouhaveabattery-operatedrecorder,turnitonandletitrunforthe20-minuteobservationperiod.Whenananimalmakesasound,notethetimeinyournotebooksothatyoucanidentifythetapedsoundlater.
Step 6—Ifyouhavebinoculars,trytoidentifynonplantspeciesthatarefaraway.Fortinyorganismssuchasinsectsandworms,useamagnifyingglass.Donotpickupordisturbanyorganisms.Yourroleistoobserve,nottointeractwithlivingthings.
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Step 7—Afteryourobservationperiodofatleast20minutesisover,markyourspotwithanaturaltrailmarkersuchascrossedsticksorastonecairn.Collectyourmaterialsandleavequietly.Completeyournotesbywritinganyotherobservationsthatyouwerenotabletonoteduringthestudyperiod.
Step 8—Visittheareaandrepeatyourobservationstwomoretimes,accordingtothescheduleyousetupinstep1.Besuretoobservefromexactlythesamespoteachtime.
oBSErvationS
1.Duringyourstudyperiods,whichchangesdidyouobserveintheplantspeciesthatyouidentified?
2.Atwhichtimesdidyouseemorenonplantspecies(e.g.,birds,insects,fungi)duringyourobservationperiod?
3.Howdidthetimeofdayorseasonaffectyourobservations?
4.Howdidenvironmentalconditionsaffectyourobservations?
conclUSionSWriteareport,basedonyourobservations.Includeyourgeneralobservationsabouttheecologyofyourstudyareas.Alsoincludeyourfindingsandconclusionsfromyourdetailedstudy.
the Greenhouse EffectThisactivitydemonstrateshowtheatmospheretrapsthe
sun’senergytowarmEarth’ssurface.
ProcEDUrEStep 1—Usingscissors,cutthetopsoffoftwo2-litersodabottles.Makeyourcutabout4inchesfromthetop.Labelonebottle“A”andtheotherbottle“B.”
Step 2—Pour2cupsofgardensoilorpottingsoilintoeachbottle.
Step 3—Placeathermometerinsideeachbottle.Makesurethethermometersareplacedatthesame
distanceabovethesoilineachbottle.
Step 4—CoverthetopofbottleBwithclearplasticwrapandsecureitwitharubberbandortape.
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Step 5—Placealamponatable,removingthelampshadetoexposethelightbulb.Positioneachbottleexactly1inchfromtheexposedbulb.Besuretoturnthebottlessothatthethermometersfaceawayfromthelightbulb.(Youmayneedtoshadethethermometersfromdirectlighttogetaccuratereadingsofairtemperatures.)
Step 6—Withthelightoff,recordthetemperatureineachbottleinyournotebook.
Step 7—Turnonthelamp.
Step 8—Usingawatch,waitthreeminutes,andthenrecordthetemperaturesagain.Recordthetemperaturesineachbottleeverythreeminutesfor15minutes.
oBSErvationS
1.Didthetemperatureineachbottlechangeduringyourexperiment?
2.Explainwhatthelightbulbandtheplasticwraprepresentinthismodelofthegreenhouseeffect.
conclUSionSCompareyourexperimentalsetuptorealconditionsonEarth.Usingyourdata,explainwhythegreenhouseeffectmakesitpossibleforlifetoexistonEarth.
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air PollutionInthisexperiment,youwillobservesomeoftheparticulatesthatpolluteair.
ProcEDUrEStep 1—Spreadathinfilmofpetroleumjellyontwopaperplatesortwowhite3-by-5-inchindexcards.Thesewillserveasyourairpollutioncollectors.
Step 2—Placeonecollectorinanurbanenvironment,suchasnearabusystreet.Placetheothercollectorinanonurbanenvironment,suchasinafieldoraforestedarea.
Step 3—Protecteachcollectorfromprecipitationbyplacingacoveraboveitorplacingitunderneathanoverhangingroofortreelimb.
Step 4—Leavebothcollectorsinplaceforoneweek.
Step 5—Retrievethecollectors.Usingamagnifyingglass,lookatthesurfaceofeachcollectortoidentifyanyparticulates.
Step 6—Placeasheetofclearplastic,markedoffinagridof1-inchsquares,overonecollector.Usingthemagnifyingglass,countthenumberofparticulatesinfourofthesquares.Findtheaveragenumberofparticulatesinasquareandrecordthisnumber.
Step 7—Repeatstep6fortheothercollector.
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oBSErvationS
1.Whatwastheaveragenumberofparticulatesonthecollectorleftinanurbanenvironment?Inthenonurbanenvironment?
2.Whatdotheparticulatesonthetwocollectorssuggestaboutthelevelofairpollutionineachenvironment?
conclUSionSUsingyourdata,reportwhatyoulearnedabouthowparticulatescontributetoairpollutioninurbanandruralenvironments.
acid rainInthisexperimentyouwilltesttheeffectofacidrainonlandplants.
ProcEDUrEStep 1—Labelfivepottedplantsofthesamesizeandspecieswiththenumbers1through5.
Step 2—Measuretheheightofeachplantwitharuler,andrecordtheheightsinyournotebook.Countthenumberofleavesoneachplantandrecordthisalso.
Step 3—Useamagnifyingglasstoexamineeachplant.Draweachplantandcolorinanyareasthatshowdamage.
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Step 4—Putonsafetygogglesandanaprontoprotectyoureyesandclothing.Measuresomedistilledwaterandvinegarintofivelabeledbottles,usingtheproportionsshowninthetable.
Step 5—Placeallfiveplantsinasunnylocation.Watereachonewiththesameamountoftapwater.Donotoverwatertheplants.
Step 6—Sprayplant1withbottle1,plant2withbottle2,plant3withbottle3,plant4withbottle4,andplant5withbottle5.Makesureyouspraythesoilineachpot,becauseplantsabsorbwaterthroughtheirroots.Usethesamenumberofspraysoneachplanteachtime.
Step 7—Waitonedayandexamineeachplantwithamagni-fyingglass.Measuretheheightofeachplantandcountthenumberofleaves.Recordthesedata.
Step 8—Repeatsteps6and7everydayforfivedays.
oBSErvationS
1.Duringtheexperiment,whatkindsofchangesdidyouseeintheleavesofeachplant?
2.NormalrainwaterhasapHofabout5.6.HowdidthepHoftheplantsintheexperimentcomparetothatofnormalrain?
3.Explainwhyyoudrewapictureofthedamagedareasontheplants’leavesbeforeyoubeganyourexperiment.
conclUSionSUseyourdataandobservationstoexplainhowacidrainaffectslandplants.
Bottle number vinegar Water pH5 1 cup none 24 4 teaspoons 1 cup 33 3 teaspoons 1 cup 42 2 teaspoons 1 cup 51 none 1 cup 7
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cleaning Up oil SpillsWhenanoilspilloccursinanaquaticenvironment,thefirststepinthecleanupprocessistryingtocontroltheoilandkeepitfromspreadingtocoastalareaswhereitwouldaffectmanywildlifespecies.Waterfowlareespeciallyvulnerabletooilspills.Theoilcoatsthebirds’feathers,causingtheirfeatherstoclumptogetherandlosetheabilitytokeepthebirdsinsulatedfromthecold.Oil-soakedbirdsoftenfreezetodeath.Othersdieafterconsumingthetoxinsfromtheoilastheyattempttoridtheirfeathersoftheoil.Atleastahalfmillionwaterbirdsdieeachyearasaresultofoilspills.Inthisexperimentyoucanexamineseveralmethodsthatareusedtocleanupoilspillsatseaandspeculateuponwhichmethodsmightworkbesttoreducetheeffectsofthespillonwaterfowl.
ProcEDUrEStep 1—Labelfouraluminumpiepans“A,”“B,”“C,”and“D.”
Step 2—Usingameasuringcup,pour1cupoftapwaterintoeachpieplate.
Step 3—Measure4tablespoonsofvegetableoil.Add1tablespoonofvegetableoiltothewaterineachpieplate.
Step 4—InpanA,useaplasticspoontostirtheoilintothewater.Then,usingastraw,trytoblowtheoilintoonepartofthepan.Becarefulnottotouchthewaterwiththestraw.
Step 5—InpanB,stirtheoilanduseapieceofstringtotrytocollecttheoilandcontainitinonearea.
Step 6—StirtheoilinpanC.Usingapapertowel,trytoabsorbtheoil.Thenusestripsofnewspaper,cottonballs,andfabricscrapstotrytoabsorbtheoil.Recordandcomparehowwelleachmaterialworked.
Step 7—StirtheoilinpanD,thenadd1teaspoonofliquiddishwashingdetergenttothewaterinthepan.
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oBSErvationS
1.Whathappenedtotheoilandthewaterwhenyouusedastrawtoblowtheoilaway?Whatconditionsatseamightthisrepresentthatwouldmakecleaninganoilspillmoredifficult?
2.HowwelldidthestringworktocontaintheoilinpanB?
3.WhichofthematerialsusedinpanCworkedbesttoabsorbtheoil?
4.Whathappenedwhenyouaddedliquiddishwashingdeter-genttopanD?Canyouexplainwhy?
conclUSionS Scientistshavedevelopedmanymethodstocleanupoilspills.Inthisexperiment,youexploredseveral.Explainwhichtreat-mentworkedbesttocleanupyouroilspill.Wouldthistypeoftreatmentbepracticalinanactualspillatsea?Considerhowcleanupmethodsmightaffectwaterfowlandotherorganisms.Isatreatmentbetterorworseforthemthantheeffectsofthespillitself?Comparethemethodsyouusedwiththemethodsexplainedintheboxaboutmethodsofoil-spillcleanupinthesection“HumanImpactontheBiosphere.”
thermal Pollution of WaterRecallthatthermalpollutionoccurswhenasourceofheatraisesairorwatertemperatureabovenormal.Thenormaltem-peraturerangesforourlakesandriversare:above68degreesforwarmwaterwheremostbassliketolive;between68and55degreesformoderatewaterwheresalmonliketolive;andbelow55degreesforcoldwaterwheremosttroutliketolive.Inthisexperimentyouwilldiscoverifalgaearesensitivetothermalpollution.
ProcEDUrEStep 1—Setuptwo10-gallonaquariumtanksorotherclearlargecontainers.Placeoneoftheminalocationwhereitwillnotgetabove60degrees.Fillthembothwithtapwater.Beverycarefulifyouattempttomoveatankafteryouhavefilleditwithwater.
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Step 2—Placeathermometerineachtankandaddaheatsource(aquariumheater,externallightbulb,ordirectsunlight)tooneofthetanks.Thistankshouldberaisedtoatemperatureover70degrees.
Step 3—Feedeachofthetankswithenoughfishfoodorliquidplantfertilizertofeedseveralfishorplantsinthetanks.Recordthedate,time,andtemperatureofeachtankinyournotebook.
Step 4—Repeatstepthreeseveraltimeseachdayforthenextsevendays.Inadditiontotheaboveinformationalsorecordanypresenceofalgaegrowingonthesidesofthetankinyournotebook.Describethealgaeandmakeasketchortakepicturestoshowthegrowthofthealgae.
Step 5—Attheendoftheexperiment,besuretocleanthecontainersandremovethealgaebuildup.
oBSErvationS
1.Whydidyoufeedthewaterinbothtanksatthebeginningandthroughouttheexperiment?Whynotjustfeedtheheatedtank?
2.Whatwasthedifferenceintemperatureofthetwotanks?Whatactivitieswouldincreasethetemperatureofariverorlakenearyoubythismuch?
3.Didyounoticeanychange(color,appearance,pattern,etc.)inthealgaeduringtheexperiment?Whatdoyouthinkmighthavecausedthis?
conclUSionSUsingyourdata,explainhowthermalpollutionmayaffectaquaticorganisms.Recallwhatyoulearnedabouthowfertiliz-erscanpromotealgaeblooms.Whyisincreasedgrowthofalgaebadforanaquaticenvironment?Howwouldthermalpollutionaffectfish,waterplants,orotherorganismsthatcannotescapefromthesourceoftheheat?Canyouspeculateabouttheeffectsofthermalpollutionintheair?
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Soil ErosionInthisexperimentyoucanfindouthowsoilerosionhappensandlearnaboutonewaytopreventsoilerosion.
ProcEDUrEStep 1—Getpermissionbeforeyoudigupanysoilforthisexperiment.
Step 2—Placecut-upstripsofnewspaperintoabucketandfillthebucketwithwater.Stiroccasionally.Leavethenewspaperinthewateruntilitfallsapartandbecomesamushymixofpaperandwater.Thismaytakeafewdays.
Step 3—Buildthreelong,narrowboxesoutofwood,shoeboxes,orplasticormetalpipe.Ifyouusecardboard,linetheboxeswithplasticbagsorfoilandcoveranyseamswithadhesiveorducttapetopreventleaking.
Step 4—Atoneendofeachbox,cutalargeV-shapednotchabouthalfasdeepastheendwallofthebox.Labeltheboxes“1,”“2,”and“3.”
Step 5—Fillboxes1and2withgardensoilsothatthesurfaceofthesoilisabouthalfaninchbelowthetopedgesoftheboxes.
Step 6—Fillbox3withsoilthathasgrassgrowingonit.Makethesoilsurfaceabouthalfaninchbelowthetopedgeofthebox.
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Step 7—Drainoffthewaterfromthenewspapermix.Takeahandfulofthemush,squeezeoutmorewater,andspreadthisontopofthesoilinbox2.Continuetodothisuntilthesurfaceofthesoilinbox2iscoveredwiththenewspapermixture.Letitsitovernight.
Step 8—Thefollowingday,lineupthethreeboxesinarow.Placeabrick,largerock,orbookundertheuncutendofeachbox.Placeacollectingpan,jar,orcupunderthelowerendofeachboxbelowthecutoutV.Photographormakeadrawingofeachbox.
Step 9—Fillthewateringcanwithameasuredamountoftapwater.Standingatthehigherendofbox1,sprinklethewateronthesoilsurfaceuntilthecanisempty.Waitaboutthreemin-utesuntilthewaterstopsrunningfromtheVnotch,andthenobservethewaterthatcollectsinthepan,jar,orcup.Measuretheamountofwaterandnoteitscolor.Recordthedatainyournotebook.
Step 10—Repeatstep9forboxes2and3,usingthesameamountofwatereachtime.Photographormakeadrawingofeachboxtoshowthechanges.
oBSErvationS
1.Describethedifferencesinthepaththewatertookineachofthethreeboxes.
2.Howmuchwaterendedupineachcollectingpanafterthreeminutes?Whatwasthecolorofthewaterineachcollectingpan?
3.Howdidthecolorandtheamountofwaterdifferineachcollectingpanafterthreeminutes?
4.Howmuchsoilendedupineachcollectingpan?
5.Thenewspapermixtureusedinbox2resemblesamixturesprayedonbaresoilatconstructionsitestopreventerosion.Basedonyourexperiment,whydoyouthinkthisisagoodidea?
conclUSionSUsingyourexperimentaldataandphotographs(ordrawings),showyourresultsonaposter.Presentyourpostertoyourcounselor.
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Biodegradable Packing materialsItemspurchasedonlineorfrommail-ordercatalogsareshippedinboxesandprotectedwithpackingmaterialsthatrangefromplasticbubblewraptopopcorn.Packingmaterialssometimesendupaslitteralongroadsidesortakeupspaceinlandfills.Inthisexperiment,youwillfindoutwhichpackingmaterialsarebiodegradable.
ProcEDUrEStep 1—Labelfourresealableplasticbags“1,”“2,”“3,”and“4.”
Step 2—Pouracupofsandintoeachplasticbag.Thenaddacupofgardensoiltoeachbag.Carefullymixthesandandsoilbysqueezingthemixtureineachbag.
Step 3—Inbag1,placesixsmallstripsofnewspaper.
Step 4—Inbag2,placesixfoampackingpeanuts.
Step 5—Inbag3,placesixpiecesofunbuttered,unsaltedpoppedpopcorn.
Step 6—Inbag4,placeasmallpieceofplasticbubblewrap.
Step 7—Filleachbagalmosttothetopwithgardensoil.(Leaveenoughspacetoallowthebagtobeclosed.)
Step 8—Pourhalfacupoftapwaterintoeachplasticbag.
Step 9—Closeeachbag.Placeallfourbagsnearasunnywindow.
Step 10—Aftertwodays,opentheplasticbags,stirthesoil,addhalfacupoftapwater,andreclosethebags.
Step 11—Waitthreemoredays,thenemptyeachbagontoasheetofnewspaperandlookforthepackingmaterialsineach.Useamagnifyingglasstoexamineeachmaterial.
oBSErvationS
1.Whichpackingmaterialsshowedsignsofdecomposition?
2.Whichdoyouthinkwerebiodegradable?Whichwerenonbiodegradable?
3.Explainthedifferencesbetweenthematerialsthatarebiodegradableandtheonesthatarenonbiodegradable.
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conclUSionSBasedontheresultsofthisexperiment,makeastatementaboutwhichkindsofpackingmaterialsarebiodegradableandwouldcreatelesssolidwaste.Whatotherkindsofbiodegradablepack-ingmaterialswouldprotectfragileitemsduringtransport?
oil Pollution on landWhathappenstotheoilthatleaksoutofenginesontoasphaltparkinglots?Whenitrains,thatoiliswashedontothesoil,whereitseepsdowntowardplantroots.Dothisexperimenttofindouthowoilpollutiononlandaffectsplants.
ProcEDUrEStep 1—Setoutapitcheroftapwaterfor24hours.Obtainfoursmallpottedplants,suchaspansiesoranotherfast-growingannualflower.Labelthepots“A,”“B,”“C,”and“D.”
Step 2—Onday1,placethefourplantsinasunnywindow.Watereachplantwiththesameamountoftapwaterfromyourpitcher.
Step 3—Usearulertomeasureeachplant.Inyournotebook,recordtheirheights,numberofleaves,andanyotherimportantcharacteristicsyouobserve.
Step 4—Pour1teaspoonofmotoroilonthesoilofplantB,makingsurenottogetanyoilontheleaves.Pour2teaspoonsofoilonthesoilofplantC.Pour3teaspoonsofoilonthesoilofplantD.DonotputanyoilonthesoilofplantA.
Step 5—Onday2,watereachplantwithhalfacupofwaterfromthepitcher.Donotoverwatertheplants.
Step 6—Examineeachplantdailyforthenextthreedays.Writeyourobservationsinyournotebook.Onday3,againmeasuretheheightofeachplantandrecordthenumberofleaves.Alsorecordinyournotebookanycolorchanges.
Step 7—Attheendofyourexperiment,disposeofthesoilcontaminatedwithoil.ContactyourlocalEPAofficesorhazardouswasteagencytofindoutwheretotakethesoilforproperdisposal.
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oBSErvationS
1.WhywasitnecessarynottoputanyoilonthesoilofplantA?
2.Whywatertheplantsafterpouringoilonthesoil?Whatenvironmentalconditionsdidthisactionimitate?
3.Whatkindsofeffectsdidyouseeintheplantsthatweretreatedwithoil?
conclUSionSOilisoneofmanytoxicsubstancesthatcanbeabsorbedbysoil.Explainwhyitisimportanttokeepcarsmaintainedsotheydonotleakoil,andtocollectusedoilfromgasstationsandgaragesforrecycling.
Endangered SpeciesEndangeredspeciescanbefoundineverystateandinmostcountriesaroundtheworld.Findoutaboutendangeredspeciesbydoingthisactivity.
ProcEDUrEStep 1—Toresearchtheendangeredandthreatenedspeciesinyourstate,contactyourstate’sdepartmentsoffishandgame,wildlife,orparksandrecreation,oryourenvironmentalprotec-tionagency.TheU.S.FishandWildlifeDepartmentreportstheendangeredandthreatenedspeciesbystate.Formoreinforma-tion,seetheresourcessectionattheendofthispamphlet.
Step 2—Listtheendangeredorthreatenedspeciesinyourstate.Chooseonespeciestostudy.
Step 3—GotothelibraryoraccesstheInternet(withyourparent’spermission)tofindinformationaboutyourchosenspe-cies.Useatleastfourdifferentreferencesources.Researchhint:Askyourlibrarianifthelibraryoffersaccesstomagazine-articledatabasessuchasProQuestorEBSCOhost.
Step 4—Findoutwhatthenaturalhabitatofthespeciesis,whyitisendangeredorthreatened,andhowmanyindividualorganismsofthespeciesareestimatedtostillliveinthewild.Ifthespeciesisnowprotectedbystateorfederallaw,explainhowthisprotectionhashelpedthespeciessurviveandwhatelseneedstobedonetoprotectthespecies.
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Step 5—Preparea100-wordreportonyourendangeredspecies.Makeadrawingofyourspeciestoincludeinyourreport.
Step 6—Presentyourreporttoyourpatrolortroop.
How Does an Endangered Species recover?Sometimesacommitmentoftime,money,andotherresourcescanbringaspeciesbackfromtheedgeofextinction.Inthisactiv-ity,youwillresearchonesuchspeciesandlearnitsrecoverystory.
ProcEDUrEStep 1—Usingresourcesyouhavefoundatthelibrary,athome,orontheInternet(withyourparent’spermission),makealistofendangeredspeciesthathaverecovered.YoucouldwritetotheWorldWildlifeFundandotherorganizationsthatfocusonplantorwildlifeconservation.Seetheresourcessectionattheendofthispamphletformoreinformation.
Step 2—Chooseonespeciesthathasrecoveredfromnear-extinctionandresearchhowitrecovered.Findoutwhatisthestatusofthespeciestoday.
Step 3—Writea100-wordreportonthespecies.
Step 4—Discussyourreportwithyourcounselor.
Bald eagle
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Activities in Environmental Science.
Environmental impact assessment Inthisactivity,youwillidentifytheitemsthatwouldneedtobeincludedinanenvironmentalimpactstatementforahypothetical(imaginary)constructionproject.
ProcEDUrEStep 1—Inyournotebook,describeaconstructionprojectthatmightbeproposedforyourcommunitybyyourlocalorstategovernment.Suggestedprojectsincludebuildinganewhigh-wayorbridgeinaruralarea;buildinganewschoolorlibraryonfarmland;buildingabicyclepathornaturetrailinawoodedarea;orpavingoveravacantlotforparkingcars.Includeadescriptionofthesizeandnatureoftheprojectandhowthecommunitywillbenefitfromit.
Step 2—Chooseasuitablesiteforyourprojectandvisitit.(Theprojectisimaginary,butthesitemustbearealplace.)Recordthefollowingdatafortheprojectsite:
a. Whattypesofplantandanimallifeareatthesite?
b. Whattypeofecosystem(forest,grassland,desert,etc.)isit?
c. Hasitbeendisturbedbefore?
d. Isitahabitatforanendangeredorthreatenedspecies?
e. Doesitslope?Wouldthesoilbeindangeroferosionduringconstruction?
f. Aretherestreamsorwetlandssuchasswampsatthesite?
g. Istherereasontobelieveimportantfossilsorartifactsareatthesite?
h. Arethereactivitiesonlandsnexttothesite?
Step 3—Describehowtheproposedprojectfitsintoexistingplansforthearea.Forexample,isthesitethelastemptylotinahousingsubdivision?Ifyouareplanningahighway,woulditcutthroughastateorlocalpark?Willabikepathallowarearesidentstobicycletoschoolorworkratherthandrivecars?
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Step 4—Suggestwaystheproposedprojectwilllikelyaffecttheenvironment.Answerthefollowingquestions:
a. Willtheprojectcausesoilerosion?
b. Willitdisturbforests,grasslands,deserts,orotherecosystems?
c. Willitdisturbanyhabitatsofendangeredorthreatenedspecies?
Step 5—Identifyanyeffectsoftheprojectthatprobablywillbeharmfulbutcannotbeavoided.Abridgeoverarivertoconnecttwoexistingroads,forexample,probablycannotbebuiltelsewhere,sotheproject’snegativeeffectsmayhavetobeaccepted.
Step 6—Suggestalternativestotheproposedprojectthatwouldprotecttheenvironment,yetstillmeettheneedsofpeople.Alternativesmayincludedifferentprojectdesignsatthesamesiteorthesameprojectbuiltatadifferentsite.
Step 7—Discussthetrade-offsbetweentheshort-andlong-termenvironmentallossesandtheshort-andlong-termbenefitsoftheproposedproject.
Step 8—Determinehowtheproposedprojectwouldpermanentlypreventotherusesofthesite.Ifavacantlotispaved,forexample,thenthatlandcouldnotbeusedforacommunitygarden.
conclUSionSBasedonyourreviewoftheproposedproject,tellyourcoun-selorwhatinformationwouldneedtobeincludedinanenvironmentalimpactstatementandwhetheryouthinktheprojectshouldgoaheadasdesignedorbestopped.Ifyourecommendstoppingtheproject,tellwhyandsuggestanyalternativedesignsorprojectsthatyouwouldsupport.
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.Environmental Science Resources
Scouting literatureConservation Handbook; Fieldbook; Animal Science, Chemistry, Citizenship in the Community, Citizenship in the Nation, Citizenship in the World, Energy, Engineering, Fish and Wildlife Management, Fishing, Forestry, Gardening, Landscape Architecture, Mammal Study, Nature, Oceanography, Plant Science, Pulp and Paper, Soil and Water Conservation, and Weathermeritbadgepamphlets
Adams,Douglas,andMarkCarwardine.Last Chance to See.HarmonyBooks,1990.
Bickerstaff,Linda.Oil Power of the Future: New Ways of Turning Petroleum Into Energy.TheRosenPublishingGroupInc.,2003.
Bowden,Rob.Waste, Recycling, and Reuse.RaintreeSteck-Vaughn,2002.
Carson,Rachel.Silent Spring.HoughtonMifflin,1962.
EarthworksGroup.50 Simple Things Kids Can Do to Recycle.EarthworksPress,1994.
Elkington,John,etal.Going Green: A Kid’s Handbook to Saving the Planet.VikingBooks,1990.
Fasulo,Mike,andJaneKinney.Careers for Environmental Types and Others Who Respect the Earth.McGraw-Hill,2001.
Hall,EleanorJ.Garbage.GaleGroup,1997.
Koebner,Linda.For Kids Who Love Animals: A Guide to Sharing the Planet.AmericanSocietyforthePreventionofCrueltytoAnimals.LivingPlanetPress,1991.
Leopold,Aldo.A Sand County Almanac.OxfordUniversityPress,2ndEdition,2000.
MacEachern,Diane.Save Our Planet.BantamDoubledayDell,1995.
O’Connor,RebeccaK.Acid Rain.LucentBooks,2004.
EnvironmentalScienceResources
For more information about Scouting-related resources, visit the BSA’s online retail catalog (with your parent’s permission) at http://www.scoutstuff.org.
94 EnvironmEntal SciEncE
Environmental Science Resources.
OfficeofSolidWasteandEmergencyResponse.Guide to Environmental Issues.U.S.EnvironmentalProtectionAgency,1995.
Patent,DorothyHinshaw.Biodiversity.HoughtonMifflin,2003.
Pringle,Laurence.Global Warming.SeaStarBooks,2001
———.The Environmental Movement.HarperCollins,2000.
ProgrammeResourceMaterialonConservation.Help to Save the World.WorldOrganizationoftheScoutMovement,WorldScoutBureau,1990.
Rathje,William.Rubbish! The Archaeology of Garbage.HarperCollins,1993.
Rybolt,ThomasR.,andRobertC.Mebane.Environmental Experiments About Land.EnslowPublishersInc.,1993.
Wilson,EdwardO.The Diversity of Life.Norton,1992.
U.S.DepartmentofAgricultureForestService.Investigating Your Environment.1993.
organizations and Web SitesEarth 9111375N.ScottsdaleRoad,Suite360Scottsdale,AZ85257Telephone:480-889-2650Website:http://www.earth911.com
Environmental Protection agencyArielRiosBuilding1200PennsylvaniaAve.,NWWashington,DC20460Telephone:202-272-0167Website:http://www.epa.gov
Keep america Beautiful1010WashingtonBlvd.Stamford,CT06901Telephone:203-323-8987Website:http://www.kab.org
natural resources conservation ServiceAttn:ConservationCommunicationsStaffP.O.Box2890Washington,DC20013Telephone:202-720-3210Website:http://www.nrcs.usda.gov
Society of american Foresters5400GrosvenorLaneBethesda,MD20814-2198Telephone:301-897-8720Website:http://www.safnet.org
U.S. Fish and Wildlife ServiceMainInterior1849CSt.,NWWashington,DC20242-0001Toll-freetelephone:800-344-9453Website:http://www.fws.govEndangeredSpeciesWebsite:http://fws.gov/endangered/
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USDa Forest Service1400IndependenceAve.,SWWashington,DC20250-0003Telephone:202-205-8333Website:http://www.fs.fed.us
advocacy organizations and Web SitesSave our EnvironmentWebsite:http://www.saveourenvironment.org
Sierra clubNationalHeadquarters85SecondSt.,SecondFloorSanFrancisco,CA94105Telephone:415-977-5500Website:http://www.sierraclub.org
World Wildlife Fund125024thSt.,NWWashington,DC20037Telephone:202-293-4800Website:http://www.worldwildlife.org
acknowledgmentsTheBoyScoutsofAmericagivesspe-cialthankstothefollowingindividualswhocontributedtheirexpertise,time,andotherresourcestothisrevisededi-tionoftheEnvironmental Sciencemeritbadgepamphlet:TimBeaty,nationalpartnershipcoordinator,Senior,Youth,andVolunteerPrograms,USDAForestService;E.LynnBurkett,publicaffairsofficer,BureauofLandManagement,U.S.DepartmentoftheInterior;StuartL.Carlson,USDAForestService;VicShelburne,Ph.D.,associateprofes-sor,DepartmentofForestResources,ClemsonUniversity;andGaryM.Stolz,Ph.D.,U.S.FishandWildlifeService.
Fortheirinvolvementandcontribution,thanksalsotoAllanBatterman,EnvironmentalProtectionAgency;JerryBernard,NationalResourcesConservationService;DavidJ.Kinsey,VirginiaOfficeofEnvironmentalEducation;LorraineV.Loken,WaterEnvironmentFeder-ation;PhilipMonson,SobranInc.;JimRyckman,EnvironmentalQualityBranch,DepartmentofPreventiveHealthServices;andDr.VonMcCaskill,thedepartmentheadofPesticideRegulationatClemsonUniversity.
WearegratefultoMarilynS.ChakroffandEagleScoutR.PaulChakroff,whocoauthoredthe1998editionoftheEnvironmental Sciencemeritbadgepamphlet,uponwhichthisneweditionisbased.Fortheircontributiontothe1998edition,thanksalsotoDr.KerryL.Cheesman,Columbus,Ohio;EagleScoutGaryA.Jacob,Medway,Mass.;RobertE.Phelps,Columbus,Ohio;JimMcKenzie;JayneBrown,Columbus,Ohio;andtheScoutsofTroop502,Westerville,Ohio.
WeappreciatetheQuicklistConsultingCommitteeoftheAssociationforLibraryServicetoChildren,adivisionoftheAmericanLibraryAssociation,foritsassistancewithupdatingtheresourcessectionofthismeritbadgepamphlet.
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Environmental Science Resources.
Photo and illustration credits
HAAPMediaLtd.,courtesy—cover(recycle bin)
NationalOceanicandAtmosphericAdministration/DepartmentofCommerce,courtesy—page26
NewYorkStateDepartmentofEnvironmentalConservation,courtesy—page39
©Photos.com—cover(all except merit badge and recycle bin); pages4,9,11–14(all), 16–17 (both), 18(bottom),19,24–25(all),26 (top), 27(all),34(top row, left and right; center row, left and center; bottom row, right),35(inset), 37,40,43–44(all),47,49,51,53,54(left),57,69,73(both),76,79–81(all),83,and92
NaturalResourcesConservationService,courtesy—page10
NaturalResourcesConservationService/TimMcCabe,courtesy—page28
NaturalResourcesConservationService/LynnBetts,courtesy—page54(right) and72
U.S.FishandWildlifeService,courtesy—page68
U.S.FishandWildlifeService/DickBailey,courtesy—page18(top)
U.S.FishandWildlifeService/LeeEmery,courtesy—page89
U.S.FishandWildlifeService/LutherGoldman,courtesy—page59(top)
U.S.FishandWildlifeService/RyanHagerty,courtesy—page59(bottom)
U.S.FishandWildlifeService/PaulMarinari,courtesy—page62(bottom right)
U.S.FishandWildlifeService/DebbieMcCrensky,courtesy—page23
U.S.FishandWildlifeService/PhilMillion,courtesy—page62 (bottom left)
U.S.FishandWildlifeService/GaylenRathburn,courtesy—page60
Wikipedia.org/AndrewDunn,courtesy—page55
AllotherphotosandillustrationsnotmentionedabovearethepropertyoforareprotectedbytheBoyScoutsofAmerica.
JackBrown—page65
TomCopeland—pages32and84
DanielGiles—pages5–6(both)and70
JohnMcDearmon—allillustrationsonpages20–22,29–31,36,38,42,46,50,58,62,and74
Merit badge libraryThough intended as an aid to Boy Scouts, Varsity Scouts, and qualified Venturers in meeting merit badge requirements, these pamphlets are of general interest and are made available by many schools and public libraries. The latest revision date of each pamphlet might not correspond with the copyright date shown below, because this list is corrected only once a year, in January. Any number of merit badge pamphlets may be revised throughout the year; others are simply reprinted until a revision becomes necessary.
If a Scout has already started working on a merit badge when a new edition for that pamphlet is introduced, he may continue to use the same merit badge pamphlet to earn the badge and fulfill the requirements therein. In other words, the Scout need not start all over again with the new pamphlet and possibly revised requirements.
American Business 2002American Cultures 2005American Heritage 2005American Labor 2006Animal Science 2006Archaeology 2006Archery 2004Architecture 2008Art 2006Astronomy 2004Athletics 2006Automotive Maintenance 2008Aviation 2006Backpacking 2007Basketry 2003Bird Study 2005Bugling (see Music)Camping 2005Canoeing 2004Chemistry 2004Cinematography 2008Citizenship in the
Community 2005Citizenship in the Nation 2005Citizenship in the World 2005Climbing 2006Coin Collecting 2008Collections 2008Communication 2009Composite Materials 2006Computers 2009Cooking 2007Crime Prevention 2005Cycling 2003Dentistry 2006Disabilities Awareness 2005Dog Care 2003Drafting 2008Electricity 2004Electronics 2004Emergency Preparedness 2008Energy 2005
Photography 2005Pioneering 2006Plant Science 2005Plumbing 2004Pottery 2008Public Health 2005Public Speaking 2002Pulp and Paper 2006Radio 2008Railroading 2003Reading 2003Reptile and
Amphibian Study 2005Rifle Shooting 2001Rowing 2006Safety 2006Salesmanship 2003Scholarship 2004Scuba Diving 2009Sculpture 2007Shotgun Shooting 2005Skating 2005Small-Boat Sailing 2004Snow Sports 2007Soil and Water
Conservation 2004Space Exploration 2004Sports 2006Stamp Collecting 2007Surveying 2004Swimming 2008Textile 2003Theater 2005Traffic Safety 2006Truck Transportation 2005Veterinary Medicine 2005Water Sports 2007Weather 2006Whitewater 2005Wilderness Survival 2007Wood Carving 2006Woodwork 2003
Engineering 2008Entrepreneurship 2006Environmental Science 2006Family Life 2005Farm Mechanics 2008Fingerprinting 2003Fire Safety 2004First Aid 2007Fish and Wildlife
Management 2004Fishing 2009Fly-Fishing 2009Forestry 2005Gardening 2002Genealogy 2005Geology 2005Golf 2002Graphic Arts 2006Hiking 2007Home Repairs 2009Horsemanship 2003Indian Lore 2008Insect Study 2008Journalism 2006Landscape Architecture 2008Law 2003Leatherwork 2002Lifesaving 2008Mammal Study 2003Medicine 2009Metalwork 2007Model Design and Building 2003Motorboating 2008Music and Bugling 2003Nature 2003Nuclear Science 2004Oceanography 2009Orienteering 2003Painting 2008Personal Fitness 2006Personal Management 2003Pets 2003
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