Geography Project deforestation in amazon.docx

Geography Project deforestation in amazon.docx

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GeographyProjectdeforestationinamazon

GeographyProject:

DeforestationintheAmazon

Background

TheAmazonRainforest,alsoknownasAmazoniaortheAmazonJungle,isamoistbroadleafforestthatcoversmostoftheAmazonBasinofSouthAmerica.Thisbasinencompassessevenmillionsquarekilometers（1.7billionacres）,ofwhichfiveandahalfmillionsquarekilometers（1.4billionacres）arecoveredbytherainforest.Thisregionincludesterritorybelongingtoninenations.ThemajorityoftheforestiscontainedwithinBrazil,with60%oftherainforest,followedbyPeruwith13%,andwithminoramountsinColombia,Venezuela,Ecuador,Bolivia,Guyana,SurinameandFrenchGuiana.StatesordepartmentsinfournationsbearthenameAmazonasafterit.TheAmazonrepresentsoverhalfoftheplanet'sremainingrainforests,anditcomprisesthelargestandmostspecies-richtractoftropicalrainforestintheworld.

However

Since2000,155thousandsquarekilometresofrainforestintheBrazilianAmazonhavebeencutdownfortimber,burnt,orclearedforagriculturaluse.Forestclearancerateshaveaveragedmorethan1.8millionhectaresperyear（roughlytheareaofKuwait）,andthedeforestationfrontierisadvancingintotheforestatarateofmorethanfourfootballfieldseveryminute.

Duringthepast40years,closeto20percentoftheAmazonrainforesthasbeencutdown—morethaninalltheprevious450yearssinceEuropeancolonizationbegan.Thepercentagecouldwellbefarhigher;thefigurefailstoaccountforselectivelogging,whichcausessignificantdamagebutislesseasilyobservablethanclear-cuts.Scientistsfearthatanadditional20percentofthetreeswillbelostoverthenexttwodecades.Ifthathappens,theforest'secologywillbegintounravel.

Inthetimeittakestoreadthisarticle,anareaofBrazil'srainforestlargerthan200footballfieldswillhavebeendestroyed.

DEFORESTATIONINBRAZIL:

60-70percentofdeforestationintheAmazonresultsfromcattlerancheswhiletherestmostlyresultsfromsmall-scalesubsistenceagriculture.Despitethewidespreadpressattention,large-scalefarming（i.e.soybeans）currentlycontributesrelativelylittletototaldeforestationintheAmazon.Mostsoybeancultivationtakesplaceoutsidetherainforestintheneighboringcerradograsslandecosystemandinareasthathavealreadybeencleared.Loggingresultsinforestdegradationbutrarelydirectdeforestation.However,studieshaveshowedaclosecorrelationbetweenloggingandfutureclearingforsettlementandfarming.Deforestationbystate

DeforestationFiguresforBrazil

Year

Deforestation

[sqmi]

Deforestation

[sqkm]

Change

[%]

1988

8,127

21,050

1989

6,861

17,770

-16%

1990

5,301

13,730

-23%

1991

4,259

11,030

-20%

1992

5,323

13,786

25%

1993

5,751

14,896

8%

1994

5,751

14,896

0%

1995

11,220

29,059

95%

2008

4,984

12,911

11%

2009

2,882

7,464

-42%

2010

2,491

6,451

-14%

1996

7,012

18,161

-38%

1997

5,107

13,227

-27%

1998

6,712

17,383

31%

1999

6,664

17,259

-1%

2000

7,037

18,226

6%

2001

7,014

18,165

0%

2002

8,260

21,651

17%

2003

9,805

25,396

19%

2004

10,722

27,772

9%

2005

7,341

19,014

-31%

2006

5,515

14,285

-49%

2007

4,498

11,651

-18%

AllfiguresderivedfromofficialNational

InstituteofSpaceResearch（INPE）data.Individualstatefigures.

*Forthe1978-1988periodthefiguresrepresent

theaverageannualratesofdeforestation.

Include:

1.Clearingforcattlepasture

2.Colonizationandsubsequentsubsistenceagriculture

3.Infrastructureimprovements

4.Commercialagriculture

5.Logging

6.Otherreasons

1.ClearingforCattlePasture

CattleranchingistheleadingcauseofdeforestationintheBrazilianAmazon.Thishasbeenthecasesinceatleastthe1970s:

governmentfiguresattributed38percentofdeforestationfrom1966-1975tolarge-scalecattleranching.However,todaythesituationmaybeevenworse.AccordingtotheCenterforInternationalForestryResearch（CIFOR）,"between1990and2001thepercentageofEurope'sprocessedmeatimportsthatcamefromBrazilrosefrom40to74percent"andby2003"forthefirsttimeever,thegrowthinBraziliancattleproduction—80percentofwhichwasintheAmazon—waslargelyexportdriven."

2.Colonizationandsubsequentsubsistenceagriculture

Asignificantamountofdeforestationiscausedbythesubsistenceactivitiesofpoorfarmerswhoareencouragedtosettleonforestlandsbygovernmentlandpolicies.InBrazil,eachsquatteracquirestheright（knownasausufructright）tocontinueusingapieceoflandbylivingonaplotofunclaimedpublicland（nomatterhowmarginaltheland）and"using"itforatleastoneyearandaday.Afterfiveyearsthesquatteracquiresownershipandhencetherighttoselltheland.Upuntilatleastthemid-1990sthissystemwasworsenedbythegovernmentpolicythatallowedeachclaimanttogaintitleforanamountoflanduptothreetimestheamountofforestcleared.

PoorfarmersusefireforclearinglandandeveryyearsatelliteimagespickuptensofthousandsoffiresburningacrosstheAmazon.Typicallyunderstoryshrubberyisclearedandthenforesttreesarecut.Theareaislefttodryforafewmonthsandthenburned.Thelandisplantedwithcropslikebananas,palms,manioc,maize,orrice.Afterayearortwo,theproductivityofthesoildeclines,andthetransientfarmerspressalittledeeperandclearnewforestformoreshort-termagriculturalland.Theold,nowinfertilefieldsareusedforsmall-scalecattlegrazingorleftforwaste.

Between1995and1998,thegovernmentgrantedlandintheAmazontoroughly150,000families.Forty-eightpercentofforestlossin1995wasinareasunder125acres（50hectares）insize,suggestingthatbothloggersandpeasantsaresignificantcontributorstodeforestation.

3.InfrastructureImprovements

RoadconstructionintheAmazonleadstodeforestation.Roadsprovideaccesstologgingandminingsiteswhileopeningforestfrontierlandtoexploitationbypoorlandlessfarmers.

Brazil'sTrans-AmazonianHighwaywasoneofthemostambitiouseconomicdevelopmentprogramseverdevised,andoneofthemostspectacularfailures.Inthe1970s,Brazilplanneda2,000-milehighwaythatwouldbisectthemassiveAmazonforest,openingrainforestlandsto

（1）settlementbypoorfarmersfromthecrowded,drought-plaguednorthand

（2）developmentoftimberandmineralresources.Colonistswouldbegranteda250-acrelot,six-months'salary,andeasyaccesstoagriculturalloansinexchangeforsettlingalongthehighwayandconvertingthesurroundingrainforestintoagriculturalland.TheplanwouldgrowtocostBrazilUS$65,000（1980dollars）tosettleeachfamily,astaggeringamountforBrazil,adevelopingcountryatthetime.

Theprojectwasplaguedfromthestart.ThesedimentsoftheAmazonBasinrenderedthehighwayunstableandsubjecttoinundationduringheavyrains,blockingtrafficandleavingcropstorot.Harvestyieldsforpeasantsweredismalsincetheforestsoilswerequicklyexhausted,andnewforesthadtobeclearedannually.Loggingwasdifficultduetothewidespreaddistributionofcommerciallyvaluabletrees.Rampanterosion,upto40tonsofsoilperacre（100tons/ha）occurredafterclearing.Manycolonists,unfamiliarwithbankingandluredbyeasycredit,wentdeepintodebt.

Addingtotheeconomicandsocialfailuresoftheproject,arethelong-termenvironmentalcosts.AftertheconstructionoftheTrans-AmazonianHighway,Braziliandeforestationacceleratedtolevelsneverbeforeseenandvastswathsofforestwereclearedforsubsistencefarmersandcattle-ranchingschemes.TheTrans-AmazonianHighwayisaprimeexampleoftheenvironmentalhavocthatiscausedbyroadconstructionintherainforest.

RoadconstructionandimprovementcontinuesintheAmazontoday:

PavingofroadsbringschangeintheAmazonrainforestandtheChineseeconomydrivesroad-buildinganddeforestationintheAmazon

4.Commercialagriculture

Recently,soybeanshavebecomeoneofthemostimportantcontributorstodeforestationintheBrazilianAmazon.ThankstoanewvarietyofsoybeandevelopedbyBrazilianscientiststoflourishinrainforestclimate,BrazilisonthevergeofsupplantingtheUnitedStatesastheworld'sleadingexporterofsoybeans.Highsoybeanpriceshavealsoservedasanimpetustoexpandingsoybeancultivation.

PhilipFearnside,co-authorofareportinScience[21-May-04]andmemberofBrazil'sNationalInstituteforAmazonianResearchinManaus,explains,"Soybeanfarmscausesomeforestclearingdirectly.Buttheyhaveamuchgreaterimpactondeforestationbyconsumingclearedland,savanna,andtransitionalforests,therebypushingranchersandslash-and-burnfarmerseverdeeperintotheforestfrontier.Soybeanfarmingalsoprovidesakeyeconomicandpoliticalimpetusfornewhighwaysandinfrastructureprojects,whichacceleratedeforestationbyotheractors."

Satellitedatafrom2004showsamarkedincreaseindeforestationalongtheBR-163road,ahighwaythegovernmenthasbeenpavinginanefforttohelpsoyfarmersfromMatoGrossogettheircropstoexportmarkets.Typically,roadsencouragesettlementbyruralpoorwholooktotherainforestasfreelandforsubsistenceagriculture.

5.Logging

Intheory,loggingintheAmazoniscontrolledbystrictlicensingwhichallowstimbertobeharvestedonlyindesignatedareas.However,thereissignificantevidencethatillegalloggingisquitewidespreadinBrazil.Inrecentyears,Ibama—Brazil'senvironmentalenforcementagency—hasmadeseverallargeseizuresofillegallyharvestedtimberincludingoneinSeptember20