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