LAND SUITABILITY EVALUATION - World Agroforestry Centre

42 Pages·2007·0.7 MB·English

GGUUIIDDEELLIINNEESS
GGUUIIDDEELLIINNEESS
LAND
SUITABILITY
EVALUATION
with a Case
LAND SUITABILITY EVALUATION
Map of Aceh
Barat District
with a Case Map of Aceh Barat District
2007
Sofyan Ritung, Wahyunto, Fahmuddin Agus dan Hapid Hidayat
INDONESIAN SOIL RESEARCH INSTITUTE and WORLD AGROFORESTRY CENTRE
ISRI
LAND SUITABILITY
EVALUATION
with a Case Map of
Aceh Barat District
SofyanRitung,Wahyunto,FahmuddinAgusandHapidHidayat
Indonesian Soil Research Institute and World Agroforestry Centre
2007
Correctcitation
RitungS,Wahyunto,AgusF,HidayatH.2007.LandSuitabilityEvaluationwithacase
mapofAcehBaratDistrict.IndonesianSoilResearchInstituteandWorldAgroforestry
Centre,Bogor,Indonesia.
DisclaimerandCopyright
IndonesianSoilResearchInstituteandICRAFholdthecopyrighttothispublication,
butencourageduplication,withoutalteration,fornon-commercialpurpose.Proper
citationisrequiredinallinstances.Informationinthisbookletis,toourknowledge,
accuratealthoughwedonotwarrantytheinformationnorareweliableforany
damagesarisingfromuseoftheinformation.Thisbookletcanbedownloadedwithout
limitationfromhttp://balittanah.litbang.deptan.go.idor
www.worldagroforestrycentre.org/sea.
"ThisdocumenthasbeenproducedwiththefinancialassistanceoftheEuropeanUnion.
ThecontentsofthisdocumentarethesoleresponsibilityofISRIandICRAFandcan
undernocircumstancesberegardedasreflectingthepositionoftheEuropeanUnion".
2007
IndonesianSoilResearchInstitute
Jl.Ir.H.Juanda98
Bogor16123,Indonesia
Tel::[phone];fax:[phone]
Email:[email protected]
http://balittanah.litbang.deptan.go.id
WorldAgroforestryCentre
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ISBN:979-3198-36-1
Design:TikahAtikah,ICRAFSoutheastAsia
PREFACE
TheTsunamiof26thDecember2004causedseriousdamagetoagriculturalland,
soilsandvegetationalongthecoastalareasofAceh.Reconstructionofdamaged
landandsoilswillrequirecarefulplanningbasedondamageintensity,nature
andsuitabilityoflandfordifferentcrops.Thisbooklethasbeenpreparedasa
guidelineforthedistrictgovernmentofAcehBaratforspatiallay-outingoftree
cropssuitableforitscoastalareas.Theprinciplesandmethodofdevelopingland
suitabilitymapscanserveasaninputinlanduseplanning.Theprinciples
explainedinthisbookletarenotsitespecificandthuscanbeappliedtoother
districts.Treecropoptionsconsideredinthisbookletarebasedmainlyon
biophysicalcharacteristicsofland.However,itisalsoimportanttoconsidersite
specificsocio-economicconditions,localcontextandfarmers'preferencesinland
useplanningprocess.Webelievethisbookletwillcontributetospatiallanduse
planninginthedistricts.
Thisbooklethasbeenpreparedasanoutputoftheproject“Trees,Resilienceand
LivelihoodRecoveryintheTsunami-affectedCoastalZoneofAcehandNorth
Sumatra(Indonesia):RebuildingGreenInfrastructurewithTreesPeopleWant”
orReGrInproject,fundedmainlybytheEuropeanUnionthroughitsAsiaPro-
EcoIIBProgram.Wealsoappreciatethescientificinteractionbetweenpartners
oftheproject-IndonesianSoilResearchInstitute(ISRI),WorldAgroforestry
Centre(ICRAF),IndonesianResearchInstituteforEstateCrops(LembagaRiset
PerkebunanIndonesiaorLRPI)andUniversityofHohenheim(Germany).
Dr.MeinevanNoordwijk Prof.Dr.IrsalLas,MS
Regionalcoordinator, Director,IndonesianCentreforAgricultural
ICRAFSoutheastAsia LandResourcesResearchandDevelopment

Content
1. Introduction ....................................................1
1.1. TheConceptofLandEvaluationandSuitability .......................1
1.2. LandSuitabilityClassification.......................................1
1.3. LandEvaluationMethods ..........................................2
2. LandQualitiesandCharacteristics ................................3
2.1. Topography.......................................................3
2.2. Climate...........................................................4
2.3. Soil... ...........................................................5
3. LandEvaluationProcedureforAcehBaratDistrict ..................11
3.1. IdentificationofLandCharacteristics.................................11
3.2. CropRequirements ................................................13
3.3. MatchingProcess..................................................13
3.4. ScreeningofLandSuitabilityforDevelopingLandUseRecommendation.14
ReadingMaterials..................................................17
Annexes..... .....................................................19

1. INTRODUCTION
1.1. The concept of land evaluation and suitability
Landevaluationisaprocessformatchingthecharacteristicsoflandresources
forcertainusesusingascietificallystandardizedtechnique.Theresultscanbe
usedasaguidebylandusersandplannerstoidentifyalternativelanduses.
LandSuitabilityisthedegreeofappropriatenessoflandforacertainuse.Land
suitabilitycouldbeassessedforpresentcondition(ActualLandSuitability)or
afterimprovement(PotentialLandSuitability).
ActualLandsuitabilityisalandsuitabilitythatisbasedoncurrentsoilandland
conditions,i.e.withoutapplyinganyinput.Theinformationisbasedonphysical
environmentdatageneratedfromsoilorlandresourcessurveys.The
informationisbasedonsoilcharacteristicsandclimatedatarelatedtogrowth
requirementsofcropsbeingevaluated.PotentialLandSuitabilityisthe
suitabilitythatcouldbereachedafterthelandisimproved.Thelandtobe
evaluatedcanbenatural(conversion)forest,abandonedorunproductivelands,
orlandcurrentlyusedforagriculture,atasub-optimallevelofmanagementin
suchawaythattheproductivitycanbeimprovedbychangingtomoresuitable
crops.
1.2. Land suitability classification
Thelandsuitabilityclassification,usingtheguidelinesofFAO(1976)isdivided
intoOrder,Class,SubClass,andUnit.Orderisthegloballandsuitabilitygroup.
LandsuitabilityOrderisdividedintoS(Suitable)andN(NotSuitable).
ClassisthelandsuitabilitygroupwithintheOrderlevel.Basedonthelevelof
detailofthedataavailable,landsuitabilityclassificationisdividedinto:(1)For
thesemidetailedmaps(scale1:25.000-1:50.000)theSorderisdividedinto
HighlySuitable(S1),ModeratelySuitable(S2),andMarginallySuitable(S3).The
“NotSuitable”orderdoesnothavefurtherdivisions.(2)Forreconnaisancelevel
map(scale1:100.000-1:250.000),theclassesareSuitable(S),Conditionally
Suitable(CS)andUnsuitable(N).Thedifferenceinthenumberofclassesis
basedonthelevelofdetailsofthedatabaseineachscale.
2 Guidelines
ClassS1 HighlySuitable:Landhavingnosignificantlimitationoronlyhave
minorlimitationstosustainagivenlandutilizationtypewithout
significantreductioninproductivityorbenefitsandwillnotrequire
majorinputsaboveacceptablelevel.
ClassS2 ModeratelySuitable:Landhavinglimitationswhichinaggregateare
moderatelysevereforsustainedapplicationofthegivenland
utilizationtype;thelimitationswillreduceproductivityorbenefits
andincreaserequiredinputstotheextentthattheoveralladvantage
tobegainedfromtheuse,althoughstillattractive,willbe
appreciablecomparedtothatexpectedfromClassS1land.
ClassS3 MarginallySuitable:Landhavinglimitationswhichinaggregateare
severeforsustainedapplicationofthegivenlandutilizationtypeand
willsoreduceproductivityorbenefits,orincreaserequiredinputs,
thatanyexpenditurewillonlybemarginallyjustified.
ClassN NotSuitableastherangeofinputsrequiredisunjustifiable.
TheSubclassesareamoredetaileddivisionofclassesbasedonlandqualityand
charactersitics(soilpropertiesandothernaturalconditions).Forexample,
SubclassS3rcislandthatismarginallysuitableduetorootingcondition(rc)as
thelimitingfactor.Furthermore,theUnitsS3rc1andS3rc2,aredifferentiatedby
thesoileffectivedepthsof50-70cmand<50cm,respectively.Thislandunit,
howeverisrarelyusedinlandsuitabilityevaluations.
1.3. Land evaluation methods
SomeLandEvaluationSystemsuseseveralapproachessuchasparameters
multiplyingsystem,parameterstotalingsystem,andmatchingsystembetween
landqualityandlandcharacteristicswithcroprequirements.
ThelandevaluationsystemusedattheCentreforAgriculturalLandResources
ResearchandDevelopment(formerlyknownasTheCentreforSoiland
AgroclimateResearchandDevelopment)istheAutomatedLandEvaluation
System(ALES)(RossiterandVanWambeke,1997).ALESisasoftwarethatuses
landcharacteristicsrequiredforplantgrowth.ALESmatchesbetweenLand
QualitiesandLandCharacteristicswiththecriteriaoflandevaluation.Forsemi-
detailedmap(1:50,000),themaincriteriausedarebasedontheGuidelinesfor
LandEvaluationforagriculturalcommodities(Djaenudinetal.,2003)withfew
modificationsinresponsetothelocallandconditionandadditionalreferences.
Forthe1:100.000-1:250.000scalethecriteriaarereferredtothatofPetunjuk
TeknisEvaluasiLahanTingkatTinjau(Puslittanak,1997).
2. LAND QUALITIES AND CHARACTERISTICS
Landqualityisthecomplexattributesoflandsandcontainsoneormoreland
characteristics.Thelandqualitycouldeitherbedirectlyobservedinthefieldor
estimatedbasedonlandcharacteristicsaccordingtotheguidelinesbyFAO
(1976).Therelationshipoflandqualityandlandcharacteristicsisdescribedin
Table1.
Table1.Therelationshipbetweenlandqualityandlandcharacteristicsusedinland
evaluationaccordingtoDjaenudinetal.(2003)
LandQualities LandCharacteristics
Temperature(tc) Averagetemperature(oC)
Wateravailability(wa) Rainfall(mm),moisture(%),Numberofdrymonths
Oxygenavailability(oa) Drainage
Rootingcondition(rc) Texture,Coarsematerial(%),Soildepth(cm)
Peat Depth(cm),Depth(cm)ofmineralinterlayeror
enrichment(ifany),Maturity/ripeness
Nutrientretention(nr) ClayCEC(cmol/kg),Basesaturation(%),pH ,
H2O
OrganicC(%)
Toxicity(xc) Salinity(dS/m)
Sodicity(xn) Alkalinity/ESP(%)
Sulfidicmaterial(xs) Depthofsulfidicmaterials(cm)
Erosionhazard(eh) Slope(%),erosion
Floodhazard(fh) Inundation
Landpreparation(lp) Surfacestoniness(%),Surfaceoutcrops(%)
Importantlandcharacteristicsinanylandevaluationincludetopography,soil,
andclimate.These,especiallytopographyandsoil,areimportantcomponentsin
determininglandunits.
2.1. Topography
Themostimportantelementsintopographyarerelief/slopeandelevation.The
reliefisrelatedtolandmanagementanderosionhazardandelevationisrelated
totemperatureandsolarradiationandthuscloselylinkedtoplantrequirements.
ThereliefandslopeclassesarelistedinTable2.