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Manual of Soil Management and Land Conservation In Samoa

A Strengthening Multi-Sectoral Management of Critical Landscapes Project Manual

Manual of Soil Management and Land Conservation In Samoa 1

Samoa,likeothersmallislandcountriesintheSouthPacificisunderthreatbyvariousfactorsaffectingtheproductivityandhealthofthesoilsduetothecontinuouscultivationofthelandandtheimpactsofclimatechange.Althoughthecountryisstilloneofthegreencountriesintheworld,itisalreadyexperiencingsignsofdepletingsoilhealth,soilerosionanddeteriora-tion.Thusaconcertedeffortbythegovernment,fundingagencies,universities,farmers’organi-zations,non-governmentorganizationsisnecessarytohelpthecountrygrapplewiththeseriousimpactsofclimatechange.

TheassistanceoftheUnitedNationsDevelopmentProgram(UNDP)infundingtheProjecton“StrengtheningMultiSectoralManagementofCriticalLandscape”(SMSMCL)isverytimelyandrelevanttohelpthecountryinconservingandprotectingitsfragileenvironmentagainstthevariousthreatsofclimatechange.

Thismanualwasconceptualizedaspartoftheoutputsoftheconsultancydonebytheau-thorswithUNDP.Themajoraimofthismanualistoprovideimportantguidelinestosupporttheoverallimplementationneedsofothersustainableandintegratedlandmanagementoutcomesoftheproject.ThismanualwasdevelopedafterseriesofnationalconsultationswithvariousstakeholdersandprojectmanagementstaffofMNRE,interviewwiththefarmers,andactualvis-itsofthedifferentvillagesintheislandsofSavai’i,Upolu,ManonoandApolima.

WehopethatthispublicationwillgreatlybenefitthepeopleofSamoainconservationandprotectionofoneofthiscountry’smostfragileandimportantresources---OURSOILS.

Preface

TheUniversityofSouthPacificAlafuaCampus,Apia,SamoaNovember,2016

ANABELLAB.TULINMOHAMMEDUMAR

Manual of Soil Management and Land Conservation In Samoa2

ACEO AssistantChiefExecutiveOfficer

ADRA AdventistDisasterandReliefAgency

FAO FoodandAgricultureOrganization

FFI FederatedFarmer’sincorporated

GEF GlobalEquityFacility

ICCRAHSS IntegratingclimatechangeRisksintheAgricultureandHealthSectorsinSamoa

ICCRIFS IntegrationofclimateChangeRiskandResilienceintoForestryManagementinSamoa

MAF MinistryofAgricultureandFisheries

MESC MinistryofEducation,SportsandCulture

METI Matua-le-ooEnvironmentalTrustIncorporated

MNRE MinistryofNaturalResourcesandEnvironment

MWSD MinistryofWomen,SocialandDevelopment

NGO Non-GovernmentOrganizations

NUS NationalUniversityofSamoa

PMU ProjectManagementUnit

SCCL SamoaCoconutClusterLtd

SCM SoilConservationandManagement

SCS SamoaConservationSociety

SFA SamoaFarmerAssociation

SLM SustainableLandManagement

SMSMCL StrengtheningMulti-SectoralManagementofCriticalLandscapes

SPC SecretariatofthePacificCommunity

SQA SamoaQualificationsAuthority

SROS ScientificResearchOrganizationofSamoa

STEC SamoaTrustEstateCorporation

SUNGO SamoaUmbrellaofNon-GovernmentalOrganization

UNDP UnitedNationsDevelopmentProgram

UNEP UnitedNationsEnvironmentalProgram

USP TheUniversityofSouthPacificAlafuaCampus

WIBDI WomeninBusinessDevelopmentIncorporated

Acronyms


Acknowledgements

Wewouldliketoacknowledgethefollowinginstitutionsandindividualswhohaveassistedusinmakingthismanual:

TheUniversityofSouthPacificSchoolofAgricultureandFoodTechnologyInstituteofResearch,ExtensionandTraininginAgricultureThestaffoftheMinistryofNaturalResourcesandEnvironmentofSamoa Fua’avaSuluimaloAmatagaPenaia FilisitaHeather Va’aeluaGraceLaulala SeumaloisalafaiAfeleFaiilagi TofilauTepaSuaesi LevaoRickyFaatonu GardeniaElisaia-Morrison

UnitedNationsDevelopmentProgram Ms.ElizabethCullity Ms.FrancesBrown Ms.FlorentineSwanneyFeero Ms.AnnePatriciaTrevor-Stanley Ms.AliitasiPetaia

ThestaffandgraduatestudentoftheSoilScienceDepartmentandSAFTSecretary Mr.DayaPerera Mr.DeanSeouti Mr.SamueluSaulia Ms.VictoriaMuavae Mr.TanielaSiose Ms.MausaliVaiaoLaumoli-Puepuemai

ThestaffofIRETA,USP Ms.DollyAutufuga Mr.DavidLeniu Ms.SeniraSu’a

ThestaffofUSPAlafuaCampusLibrary Ms.BettyPinati Ms.LinaSolomona Ms.LaineAlatise

ThefarmersthatwehaveinterviewedduringoursurveysMr.MaiavaVeniGaugataoandMsNatiaLemoaFaafetewhohelpedusintheparticipatoryassess-mentsurveyinSavaiiThevariousstakeholderswhoattendedthestakeholders’meeting


Table of Contents

Preface 1Acronyms 2Introduction 4TheImportanceofSoilinSoilConservationandManagement 5ImportanceofSoilErosionandLandDegradation 6SomeImportantConservationPractices 7A.ImportantPhysicalPropertiesAffectingSoilManagement 8

Soil Texture 8Soil Structure 12Soil Color 15Soil Permeability 16

B.MethodsOfSoilFertilityAssessment/Evaluation: 18C.MultipleSpeciesCropping 20D.WindbreaksAndShelterBelts 21E.SurfaceCover/GroundCover 22F.MinimumTillage 23G.FertilityMaintenance/OrganicAgriculture 24H.Agroforestry 25I.Permaculture 26J.SoilErosionControlMeasures 28K.Rehabilitation 29L.IntegratedPestManagement 29M.WaterManagement. 30

Conclusion 32Recommendations 33Acknowledgement 34References 35


Introduction

ThismanualwasdevelopedtohelpthepeopleofSamoaprotectandpreserveoneofthemostimportant.Naturalresourcesthatanycountryintheworldpossesses,andthisisoursoilresources.FromoursurveysinSamoa,wefoundoutthatatthisstagesoilerosionisnotyetamajorprobleminthecountrysincewesawverylittlecasesofsoilerosionduringourtravels.Whatismoreevidentthoughistherapiddeteriora-tionofthepropertiesofthesoilinmostcaseswhichimpliedthedecliningfertilitystatusofthesoilinthiscountry.Soasidefromsoilerosion,wedecidedtoincludeinthismanualsomewaysassessingthefertilitystatusofthesesoilsaswellastheimportantphysic-chemicalpropertiesofthesoilthatthefarmersshouldbeawareof.Wealsoincludedsomevideosandvideolinksattachedinthisdocumentfortheextension

agentsandstakeholderstoaccesstoandsharewithourfarmers.


Thedependenceofhumansocietyonthesoilforfoodandfibrecouldbetracedbackinthebeginningofcivilization.Duringthesetimes,peoplehaveestablisheddifferentwaystomanagethesoils;however,notallofthesehavebeenverysustainableasevidencebythecollapseofsuccessivecivilizationsindifferentpartsoftheworld(Hillel,1992).Inthelastfewyearsespeciallywiththeadventofclimatechange,soiluseandmanagement..Havebeengivenmoreemphasisonthecontextofsustainabilityofanecosystem,whetheritbeanagriculturalornaturalecosystem,whereinthesoilplayamajorpart(Hartemink,etal.,2009).Oneofthemajorchallengesinmanagingthesoilsissoilerosionwhichhasgreatlyaffectedthedegradationofourfinitesoilresources.Thischallengeismoreamplifiedinthecaseofhighlyweatheredsoilsofthehumidtropics.Lal(1981)suggestedthatinmanagingtropicalsoils,theconceptofaholisticland-managementapproachtosoilandwaterconservationmustbeemployed.Thismanualoutlinesthedifferentwaysofsoilconservationandmanagementstartingfromthephysicalpropertiesofsoilstosoilfertilityandplantnutritionuptosomeofthemostimportantsoilerosioncontrolmeasuresthatareappli-cableinSamoa.Inthismanual,wealsofocusonthemanagementofsoilsinthecontextofcropproduction

andsoilconservation.

The Importance of Soil in Soil Conservation and Management


Importance of Soil Erosion and Land Degradation

Soilerosionhasbeenconsideredamajorenviron-mental problem besetting developing countriesforsolongandgovernmentshavedonenumerousprograms and introduced policies to promote soilconservation technologiesamong farmers (Cramb,2000).Yetinspiteoftheseeffortstheresultsworld-wide has been disappointing. Most probably be-causeofthevariousconstraintsthathavegreatlyaf-fectedtheimplementationsoftheseprojects.Since1960, farmershave tocontinuouslyproducemorefoodtofeedtheunprecedentedincreaseinhumanpopulation.Astheratioofpeopleto landsteadilyincreases,poorpeopleareforcedtoclearandburnsteep,forestedslopesorplowupnaturalgrasslandstoplanttheircrops(BradyandWeil,2010).Popula-tionpressureslikewisecompoundedtheseeffects,which led to overgrazing of rangelands and theoverexploitation of timber resources for fuel andotheruses.Alltheseactivitiesleadtotheintensifi-cationofecologicaldeterioration,landdegradationanddeepeningpoverty.

During thepast half century, human landuse andrelatedactivitieshavedegradedsome5billionha(about 43%) of the total Earth’s land (Brady andWeil,2010).Degradedlandssufferfromdestructionofnativevegetationcommunitiestherebyreducingbiodiversity, reduced agricultural yields, loweredanimalproductionandgreatlyaffectingtheoncedi-verseecosystemsprevailingineachregionorcoun-tries.

The two main components of land degradationwhich isdamagetoplantcommunitiesandvdete-riorationofsoilinteracttocauseadownwardspiralof accelerating ecosystem damage leading to lowproductivity and increasinghumanpoverty (BradyandWeil,2010).Thusitiseminentthatinordertocounteract thesenegativeeffects, improvement inbothsoilandvegetationmanagementmustgoto-gethertoregaintheproductivepotentialofthelandtomakeitmoresustainableforcropproduction

HereinSamoa,itisindeedhighlycommendabletohavethisprojecton“StrengtheningMulti-SectoralManagement of Critical Landscapes” to helpmiti-gatethisproblemoflanddegradationbeforeitwillbecomeamajorenvironmentalhazardorcatastro-phehereinSamoa.Thisisthemainreasonwhythismanualwas done to help the farmers to properlyconserve their fragile and limited soil resourcesatthesametimecontrolerosionwhichtheyseeithappeningintheirrespectivefarms.

These practices presented in this manual wereadapted fromCatalogueofConservationPracticesforAgricultureonSlopingLandpublishedbySEAR-CA(1998).However,theexamplesofthesepractic-es thatwerepresented in thismanualwere takenfrom different locations in Savaii,Upolu, ManonoandApolima-taiduringour soil surveyandpartic-ipatory assessment surveys. It is worth noting inthismanualthatmostofourexamplesweretakenactuallyinthefarmers’fieldwhichisastrongindi-cationthatindeedsoilconservationmeasureshavealreadybeenpracticedby themajorityof farmershereinSamoa.

Whatisnecessarynowistohighlightthesepractic-es ina simplemanner so that itwillbeeasier forotherfarmerstofollowthem.Belowarethelistingof thevarioussoil conservationmeasures thatwefeelshouldbeadoptedinSamoatopreventfurtherdeteriorationofourfragilesoilresourcesandmostimportantly toencourageamongour stakeholderstheir contribution in protecting the soil environ-mentsofSamoa.Inthisinitiative,everybodyshouldplayanimportantinconservingandprotectingoursoil resources and theecosystemas awhole. It isalsoworthnotingthatbeforewediscussedanysoilconservationpractices,wefirststartwiththeimpor-tanceofsoilsinourecosystemandinsustainingthegrowthanddevelopmentofplants.


Some Important Conservation Practices

A ImportantPhysicalPropertiesAffectingSoilManagement

B MethodsOfSoilFertilityAssessmentAndEvaluation

C MultipleSpeciesCropping

D WindBreakAndShelterBelts

E SurfaceCover/GroundCover

F MinimumTillage

G FertilityMaintenance/OrganicFarming

H Agroforestry

I Permaculture

J SoilErosionControlMeasures

K Rehabilitation

L IntegratedNutrientAndPestManagement

M WaterManagement

ThefollwingareafewconservationpracitcesapplicableinSamoathatareincludedinthismanualarethefollowing:


A. Important Physical Properties Affecting Soil Management

a. Eachsoilseparaterepresentsadistinctphysicalsize group.Mineral particles less than 2milli-metresinequivalentdiameterandrangingbe-tweenspecifiedsizelimits.Thenamesandsizesofthe7soilseparatesrecognizedintheUnitedStatesareasfollows:

c. Think of this relationship for the three maingroups:

• sand-basketball (sandmaybeseenwith thenakedeye)

• silt-golfball(siltparticlesmaybeseenwithagoodmicroscope)

• clay-pin(claycanonlybeseenwithanelec-tronmicroscope)

Modifiers that areused for coarsematerial that isgreaterthan2mm.

Thetermsoilseparatereferstoaspecificsizeofaparticle and not the composition of that particle.However,certainmineralswilltendtodominateormakeupthevariousseparates.

A soil’s texture is then the relative proportion ofsand, silt, and clay. Together, the three separatesmustadduptobe100%.Theorganicmatterisnotapartof the soil’s texture. Since thereare suchalargenumberofcombinationsthatcouldoccur,soilscientists group similar amounts of sand, silt andclayintogroupscalledsoiltexturalclasses.

VeryCoarseSand 2.0-1.0mm

CoarseSand 1.0-0.5mm

MediumSand 0.5-0.25mm

Fine Sand 0.25-0.10mm

VeryFineSand 0.10-0.05mm

Silt 0.05-0.002mm

Clay 0.002mm

Gravels 2mm-3in

Cobbles 3in-10in

Stones 10in-24in

Boulders 24in

Sands generallymadeupofquartz

Silts commonlycomposedofquartzandfeldspars

Clays secondaryminerals,claymineralsandFeoxides

Sand 2.0-0.05mm

Silt 0.05-0.002mm

Clay <0.002mm

Tohelpourfarmersfullyunderstandtheimportantphysicalpropertiesimportantinsoilmanagement,theyarepresented inavery simple texts thatareeasilyunderstoodbyourfarmersandotherstake-holders. An accompanying video about these soilproperties will also be presented to them duringthetraining.

Featuresofthesoilprofileandthesoilhorizonsareoften described in the field in terms of the soil’sphysicalproperties.Horizonsaredefinedbasedondifferenceinthephysicalproperties.Horizonsdif-ferfromhorizonsaboveandbelowbysomephysi-calproperty.Soilphysicalpropertiesaffecttheap-pearanceandfeelofasoil.Themajorsoilphysicalpropertiesare:

• SoilTexture• Soil Structure• SoilConsistence/SoilStrength• SoilColor• SoilPermeability• SoilTemperature

b.Wewillbeusingtheseseparatesinthetraining

Soil Texture


Textural Classes: Thetexturalclassisdeterminedbythecombinedportionofsand,siltandclayTexturalclassaffectspropertiesandmanagementofsoils.

Thesmallertheparticlesize,thegreaterthetotalsurfaceareaofagivenvolumeofsoil.SoiltextureisdeterminedinthelaboratoryquantitativelyusingtheHydrometerMethodandqualitativelybytheFeelmethodbyusingourfingers.

Soil Texture By Feel Flow Chart

Place approximately two teaspoons ofsoil in your palm. Add a few drops ofwater and kneed soil to break downall the aggregates Soil is at properconsistency when it feels plastic andmoldable, like moist putty.

Add dry soil tosoak up water

Start

Does the soilremain in a ball

when squeezed?

Is the soil toodry?

Is the soil toowet?No

Yes

No SandNo

Place ball of soil between thumb and forefinger, gently pushing the soilwith your thumb, squeezing it upward into a ribbon. Form a ribbon ofuniform thickness and width. Allow the ribbon to emerge and extendover forefinger, breaking from its own weight. Does the soil form aribbon?

Yes

Yes

LoamySand

No

Does soil make aweak ribbon < 1"

long before itbreaks?

Does soil make amedium ribbon

1-2" long before itbreaks?

Does soil make astrong ribbon > 2"

long before itbreaks?

No

Yes

No

Does soilfeel verygritty?

Neithergritty norsmooth?

Does soilfeel verysmooth?

SandyLoam

Loam

SiltLoam

Yes

Yes

Yes

No

No




SandyClay

Loam

ClayLoam

SiltyClayLoam

Yes

Yes

Yes

No

No




SandyClay

Clay

SiltyClay

Yes

Yes

Yes

No

No

Excessively wet a small pinch of soil in your palm and rub it with your forefinger.

% CLAY

%SAND

HI

LO HI


SiltLoamRibbon SandyLoamRibbon ClayLoamRibbon

Thetexturalclassesaredeterminedusingthetexturaltrian-gle.Thereare12texturalclasseswhichinclude

• theclay• sandyclay• siltyclay• clayloam• siltyclayloam• sandyclayloam• loam

• sandyclay• sandyloam• loamysand• sand• loam• silt loam• silt

from:BradyandWeil,1999

from:BradyandWeil,1999

SurfaceArea• 1gofsand=1.5ft2• 1gofsilt=14.9ft2• 1gofclay=262,467ft2

SurfaceAreaaffectsthe:• adsorptionofwater• area for chemical reactions• adsorptionofnutrients• plasticity• shrink/swell

Feel Method of Texture Determination

HydrometerMethodofTextureDetermination

TheTextualTriangle


Texturealsoinfluences:• porosity(amountandsizeofpores)

Sincemostreactionsandwaterholdingcapacityarerelatedtosurfaces,youcanseethatclaywillbeveryreactiveandholdmuchwater.

Textureislargelydeterminedbyparentmaterialandtheamountofweathering

SoilTextureandManagement• CoarseTexturedSoils(sands,loamysands)

• Holdlowamountsofwaterandnutrients-mayhavetoirrigateandfertilizefrequently• Nothighlyerosive-allowswatertoinfiltrate;lessrunoff• Verypermeable-goodforwastedisposalonlyifadeepsoil• Maycompacttoformahardpan

• Finetexturedsoils(clays,sandyclays,siltyclays)• Holdlargeamountsofnutrientsandwater-mayholdthingstootightly• Erosion-slowinfiltration;highrunoffmeansmucherosion.• Slowpermeability-oftenunacceptableforseptictanks• Mayshrink/swell-dependsuponthetypeofclaymineralsprese

• MediumTexturedSoils(loams,clayloams,sandyloams,siltloams)• Propertiesfallinbetweentheothertwo.

• Textureismodifiedbysoilformation:• Ahorizon-coarsetextured• Ehorizon-coarsetextured• Bhorizon-finetextured

• Generally, texture of a field can’t easily bechanged

• tooexpensivetoaddenoughmaterial• notreallypractical

Sand fewlargepores lowwaterholding

Silt manymediumpores highplanywaterholding

Clay manyfinepores hightotalwaterholdingnotallavailabletopalnts

• plantavailablewaterholdingcapacity


Soil Structure

Structureisthearrangementofprimarysand,siltandclayparticlesintosecondaryaggrgatescalledpedsorstructuralunitswhichhavedistinctshapesandareeasytorecognize.Thesedifferentlyshapedaggre-gatesarecalledthestructuraltype.Thereare5basictypesofstructuralunits:

1.Platy: Plate-likeaggregatesthatformparalleltothehorizonslikepagesinabook.• Thistypeofstructuremayreduceair,waterandrootmovement.• CommonstructureinanEhorizonandusuallynotseeninotherhorizons.

Example of platy structure

Example of sub angular bocky structure

Example of prismatic and columnar structure

2. Blocky: Twotypes--angularblockyandsub-angularblocky• ThesetypesofstructuresarecommonlyseenintheBhorizon.• Angulariscube-likewithsharpcornerswhilesubangularblockyhasroundedcorners.

3. Prismatic: Verticalaxisislongerthanthehorizontalaxis.Ifthetopisflat,itisreferredtoasprismatic.

• Ifthetopisrounded,itiscalledcolumnar.


4. Granular:Pedsareroundandporous,spheroid.ThisisusuallythestructureofAhorizons.

5. Structure less:Noobservableaggregationorstructuralunits.Singlegrain-sand

Example of granular structure

Spheroidal Platy

Angular Blocky Subangular Blocky

Columnar Prismatic

Example of structural types:


2. Grade of structure - Describesstabilityoftheaggregates.

• structure less • weak • moderate • strong

3. Class of structure - Describessizeoftheaggregates.

• veryfine• fine• medium • coarse • verycoarse

The size of each category varieswith the type ofstructure.

4. Formation of soil structure • freeze/thaw• wetting/drying• rootpressure• microorganisms• cementingbyclay,organicmatter,ironand

aluminumcompounds5. Importance of Soil Structure • Increases infiltration of water, thus reducing

runoffanderosionandincreasestheamountofplantavailablewater.

• Improves seedling emergence, root growthandrootingdepth.

• Largecontinuousporesincreasepermeability.

6. Maintaining Soil Structure i. Tillsoilonlyatthepropermoisturecontents.

Never tillwhen the soil is toowet. Thiswillcause thesoil tobecomecloddy.Aggregatesareeasilydestroyed.

ii. Addtheproperamountsoflimeandfertilizer.Properplantgrowthwillleadtothedevelop-mentofgoodsoilstructure.

iii. Growgrassesandlegumes.Theseplantsmayhelp form unstable aggregates and their or-ganicmatterwillhelpstabilizetheaggregate.

iv. Growthoflegumeswillalsogivethesoilmoremicroorganismswhichgivecertainbeneficialfungiwhichwillstabilizepeds.

v. Maintainor increaseorganicmattercontentsofAhorizon.plantcovercropsinfallandwinterplantmoregrassesturnundercropresidueadd manure


Soil Color

Example of a multi colored soil horizon:

Soil Color Measurement

MunsellColorSystem

Hue: dominantspectralcolorValue: lightness-darkness;whitetoblackChroma: colorpurityorintensity

Feoxides;red,yellow,andlightbrowncolors• organicmatter;darkbrownorblackcolors• lowcolorvalue=highorganicmattercon-

tent• highchroma=welldrainedsoil,oxidizing

conditions

Itisthemostobviousandeasilydeterminedsoilpropertyithaslittledirecteffectonthesoil,butisanin-dicatorofsoilproperties.However,therearemanythingswecantellaboutthesoilbyobservingthecolor.Organicmattercontent;themoreorganiccontentthedarkerthesoilcolorSoilcolorandsoiltemperature:

dark colored soils absorb more heat so they warm up quicker and have higher soil temperatures. Soilcolorandparentmaterial:

generally dark parent material will develop into dark soils. Soilcoloranddrainage:-

soil drainage refers to the length of time a soil is waterlogged. Not how fast the soil is drained.

Relationship to Drainage SoilColorisveryimportantindeterminingasoilsdrainageanddepthtothewatertable.Itcanbeveryimportantinpredictinglandusehazards.

Soil Drainage: referstothelengthanddurationofsaturation.• Itisnotameasureofhowfastwaterdrainsfromthesoil

Soil Drainage Classes • Welldrained-nograycolorsthroughouttheBhorizon• Mod.Welldrained-graycolorsormottlesinthelowerBhorizon• Somewhatpoorlydrained-graycolorsintheupperBhorizon.Mottlesalsoseen• Poorlydrained-graycolorsthroughouttheentireBhorizon


Soil Permeability Permeability - ability of soil to transmit water or air. Expressed as cm of water/hour

Soil permeability vs. Soil drainagePermeability isthespeedofairandwatermove-ment in a soil -- this is affected by texture andstructure

• ifpermeabilityishigh:watermovesquickly• ifpermeabilityislow:watermovesslowly

Drainage is the frequency and duration of satura-tion.Thetimethatthesoiliswaterlogged.-thisisaffectedbylandscapepositionandpermeability

Anotherwaytoviewthis is;drainagereferstotheamount of oxidationwhichhas takenplace in thesoilandpermeability

•Asandcouldbepermeable,butinalowland-scapepositionandbepoorlydrained.•Aclaycouldbeverypermeable,but inalowlandscapepositionandbepoorlydrained.•Aclaycouldbeimpermeablebutwelldrainedbecauseitisatthetopofahill.

Factors affecting permeability1. Pore size present in the soilWater moves faster through larger pores than smaller pores. - the bigger the pore the more material it will move.

2. Pore Continuity High permeability - contains pores which are con-tinuous and large enough for air and water to pass through.

Continuous

Discontinuous•Justbecauseasoilcontainsalargeamountofporesdoesn’tmeanitispermeable.Theporescouldbediscontinuousorverysmall.

•Anyfactorthatwillaffectporesizeorcontinui-tyofporeswillaffectpermeability.

•Thismeanssoilpermeabilityisrelatedtosoiltextureandsoilstructure.

3. Texture Pores size decreases with smaller particle size. As the

size of the separates decrease so does the pore size, but remembers that the surface area will increase quickly.

TexturalclassPermeability

Sand VeryHigh

SandyLoam

Silt,Loam High

SiltLoam Med-Low

Clay Low

4. Soil structure is related to the continuity of the pores

Themorewellstructuredasoilthemorepermeableitwill be. A soilwith good structurewill bemorepermeablethanasoilofthesametexturethathaspoorstructure.Natural aggregation of the separateswill increasethelargeporespace.Whensoilswithgoodstructurearecompactedthelargeporespaceislostbecausethebigporesaresquashed.

This means for a soil manager, the only way tochangepermeabilityistochangesoilstructure.Thisiswhyitisimportanttomaintaingoodsoilstructureifitalreadyexists.

If changes in pore size occur then changes in thepermeabilitywilloccur.

WatermaybackuponthetopoftheBhorizon.

Canbewaterloggingforshortperiodsoftime.Ifwa-terloggingpersists,plantrootsmaydieduetolackofoxygen.

Bedsofsoilorridgesmayhelpkeeptherootsabovethebhorizonandoutofthewaterloggedsoil.

Otherwaystoaffectpermeability:• Rootandwormchannels:increasepermeability

by forming large continuous pores throughoutthesoil.Theseporesmustextendfromthesoilsurfacetodepth.Theseallowforrapidwaterin-filtration.

• Organicmatter:increasespermeabilityby:• increasingthestabilityofsoilaggregates.Re-

member that organic matter decomposes toformglues,gums,etc. ... thathelpcementorsticksoilparticlestogether.

• Organicmatterformslargeporeswhenplantresiduesareaddedorleftonthesoilsurface.


Soil Consistence : Expresses cohesiveandadhe-sive forces holding soil particles together; varieswithmoisturecontent.Describestheresistanceofa soil at variousmoisture contents tomechanicalstressormanipulation.

Described at three moisture levels:Wet• Stickiness (non-sticky, slightly sticky, sticky,

verysticky)• Plasticity(non-plastic,slightlyplastic,plastic,

veryplastic)

Moist• Veryfriable,friable,firm,veryfirm

Dry • Loose.Soft.slightlyhard,hard,veryhard,extremely

hard

Consistence indicates• amountandtypeofclaymaterial• conditionfortillage• potentialforcompaction

Consistenceistheresistanceofthesoil todeformorrupture.Soilconsistenceistheforcesofcohesionandadhesionthatareholdingthepedstogether.Itrefers to thedegreeofplasticityandstickinessofthesoil.Soilconsistenceisaffectedbythetypeandamountofclaythatisinthesoil.

Soil consistence indicates:• Where are zones thatmay restrict root growth

andseedlingemergence?• Whether a soil is likely to develop compacted

zones;ruts,crusts,hardpansetc...

Determining soil consistenceFingers - squeeze aggregates or push fingers into

thesoil.Penetrometer - measures how hard it is to push into

the soil. This would be the same effect as a plant root.

Examineroots:roots or a root mat indicate problems. Sand has a very weak consistence; there is little force between the particles. This means that a car tire can easily push the sand apart and it is easy to get stuck.

Factors Affecting Soil Consistence3MajorFactors

» WaterContent » SoilTexture » SoilDensity

Water Content -thisisthemostimportant.• Soilparticleswillmovemoreeasilywhenina

wetsoil.Waterwillactasalubricant• Soilstrengthincreasesasthesoilsdriesout.• Soils will compact, become denier, if tilled,

trampled,drivenover,etc.....whenwet.

Ifasoilisworkedortilledwhenwet:• Soilhas lowstrength,particleswillbeeasily

moved.• Soils under wheels will be compacted (bulk

densityincreases).• Large pores are destroyed; cracks between

pedsandoldrootchannelsaresquashed.• As soils dries, its strength increases. Roots

maynotbeabletopushparticlesaside.• Rootgrowthmayberestricted• Thesesystemsaremoresusceptibletodrought

andmaynotgetallfertilizerthatispresent.

Soil Texture• Soil strength increases with increasing clay

content• Clayeysoilsarestrongerthansandysoils.

Soil Density• Asdensityincreasessodoessoilstrength.You

have more material in the same area whichmakesitharderfortheplantroottogrow.

Measurements of pore spaceSoil bulk density• Itisameasureofhowcompactordenseasoil

is.• Itisweightofsoildividedbythetotalvolume

(lbs/ft3org/cm3ormg/cm3)• Density=mass(weight)/volume

Bulk Density• Relatesweightofsolidstototalvolumeofsoil

includingsolidsandpores.• Affectedbyboththenatureofslidesandthe

volumeofpores.• BulkDensity=weightofovendrysoildivided

bythesoilvolume• Ifa100cubiccmsoilsamplehasanoven-dry

weightof150gramsthen

SoilBulkDensity OverdryWeight

150g=

=

Volume

100cm3

1.5g/cm3

=


• highporespace=lowbulkdensity• lowporespace=highbulkdensity

» finetexturessiltloams,clay,clayloam-gener-allylowerbulkdensity1-1.6g/cc

» 1.sandysoilsmayrange1.2-1.8g/cc » 2. strong structure (well granulated topsoil) -lowbulkdensity

» 3.highorganicmatter=lowbulkdensity

As bulk density increases:• soilstrengthincreases• porespacedecreases• soilsbecomemorecompact

Remember that bulk density is related to the amount of pores in the soil.• the greater the total pore space the lower the

bulkdensity

Afterknowing thesephysicalpropertiesof thesoil, it is important toknowhowtoproperlyassess thefertilitystatusofthesesoils.Someofthecommonwaysofassessingthefertilitystatusofthesoilthatthefarmers,extensionagentsandotherstakeholderscandoincludethefollowing:

Afterknowingthesephysicalpropertiesofthesoil,itisimportanttoknowhowtoproperlyassessthefertilitystatusofthesesoils.Someofthecommonwaysofassessingthefertilitystatusofthesoilthatthefarmers,extensionagentsandotherstakeholderscandoincludethefollowing:

B. Methods Of Soil Fertility Assessment/Evaluation:

SoilTesting–asoiltestisachemicalmethodofestimatingthenutrient-supplyingcapacityofasoil.Thismeasurestheamountsofavailablenutrientsthatthesoilcansupplytotheplants.Theobtainedvalueseitherqualitativelyorquantitatively.Thekeytothesuccessofsoiltestingisthepropercollectionofsoilsamples.Portablesoiltestkits(whichareavailableattheCentralAnalyticalSoilScienceLaboratoryofUSPAlafuaCampus)canbeusedindoingsoiltestingrightatthefarmer’sfield.

2. VisualAssessmentofhealthyplants-Thisprac-tice involved theobservationof thegrowthofthe plants as they occur in the field. Deficien-cysymptomscanbeeasilyidentifiedusingourowneyesastheyappearinthefield.Forexam-ple,mobilenutrientssuchasN,P,KandMgshowdeficiency symptoms in older leaves. On theotherhand,immobileelementssuchasSandCaandmajorityofmicronutrients suchas Fe,Mn,B,Zn,Mo,CoandCushowdeficiencysymptomsinyoungerleaves.Examplesofdeficiencysymp-tomsinplantsareshownbelow.

Ndeficiencyincorn Pdeficiencyincorn Kdeficiencyintomato

Bulk density is affected by the solids and pore space


TomatoplantsshowingN,P,Kdeficiencysymptomsascom-paredtothecontrolandplantreceivingallthenutrients

(complete).

Nitrogendeficiencyincorn

Phosphorusdeficiencyincorn

N,P,andKdeficiencysymptomsincornascom-paredwithahealthyplant

Thesoilandthevariousmacroandmicronutrientsimportantinplantgrowth.


C. Multiple Species Cropping

Thispractice involvestheplantingof twoormorecropsonthesamelandtoincreaseproductivity,di-versityandstability.

Thisusuallyusesavarietyofplantspecies,whetherannual,perennial,woody,orherbaceousplants,forfood,forageorfuel.

This soil conservationmeasure can be applied inflatlandsandhillyareas.

With this practice, a farmer can increase the effi-ciencyofresourceuselikesunlightandsoil.

Planting different species of plants in MalaefonoOrganicFarminSaleimoa,UpoluIsland,Samoa

Plantingdifferentspeciesofcropsinafarmer’sfieldinSavai’iIsland,Samoa

Another example of multiple species cropping aspracticedinSavai’iIsland,Samoa.

MultiplespeciescroppinginUpoluisland,Samoa

MultiplespeciescroppinginManonotai,Samoa MultiplespeciescroppinginApolimatai,Samoa.


D. Windbreaks And Shelter Belts

Thispracticeusestreesorshrubswhichareplantedatthebordersorfarmboundariestoprotectadjacentfieldsfromdestructivewinds.Thesearebettersuitedinareaswithflattoslightlyrollingtopographies.

Windbreaksareabarriertoprotecttheplantsfromwindsandthisisusuallyassociatedwithhomegar-dens,orchardandothers(TripathiandSingh,1993).

Shelterbeltson theotherhand, includeacombina-tionofshrubsandtreesintendedfortheprotectionoffieldcropsandtheconservationofsoilandwater.

Someofthesuggestedwindbreaksforspecifictypesofsoilsarepresentedbelow:

. Shallow soils – Eucalyptus camaldulensis andCasuarinaequisetifolia

. Semi-rockyareas-Acacianilotica,Proposisjuli-foria

. Roadsideavenueandwindbreakplanting:

. Prosopisjuliflora, Azadirachtaindica and Albiz-zialebekwerefoundsuitableforlowrainfallar-eas(120-350mm)andhighrainfallareas(>350mm)

TreesusedaswindbreaksinSili,Savaii,Samoa.

HardwoodtreesandornamentalsusedaswindbreaksandfarmboundariesintheislandofUpolu,Samoa.

NarratreesusedasfarmboundaryinSavai’iIsland,Samoa.


E. Surface Cover / Ground Cover

GrassesusedasmulchinatarofarminUpoluIsland,Samoa.

Thispracticeinvolvestheuseofprovidingaprotec-tive cover to soil surface to reduceerosion.Whenthesoilisblanketeditwillreducetheimpactofthesplasheffectscausedbyraindropstherebyreducingwaterflow(Cook,1998).

This will increase infiltration, reduce runoff andminimizeerosion.Surfacecoverseitherareacovercrop;pasture;groundcoverormulch.

Someofthemosteffectivegroundcoversarethosewith rhizomes or stolons such as buffalo grass,creepingpeanut,pintopeanut,centro,carpetgrassandmanyothers. Inorder for thegroundcover tobehighlyeffective,theymustbefastgrowing,non-orweaklytwining,shade-tolerant,anditshouldnot

actasanalternativehosttocroppestsanddiseases.

As a soil conservationmeasure, ground coverwillsolvetheproblemsoferosion,run-offanddecliningsoil fertilityat thesametimecontrol thedevelop-mentofweedsinthearea.ThistypeofpracticehasbeencommonlyusedinSa-moaespeciallyoncoconutplantationsinSavai’iandUpoluIsland.

Thetypesofgroundcoversthatareadoptedbythefarmershereincludegrassesandleguminousplants.Theyareeithergrownonthesoilasinthecaseofcoconuts or allowed to decompose and used asmulchasinthecaseoftaro.Thispracticeimprovessoilquantitybyinterceptingtheerosiveimpactsofrainfallanditwillholdsoilparticlesinplace.

Grassesandlegumesusedasgroundcoverunderacoco-nutfarminSavai’iIsland,Samoa.

GrassesusedasmulchinataroplantationinSavai’iIsland.

Theuseofgrassesasgroundcoverinacoconutplanta-tionnearthecoastalareainUpoluIsland,Samoa


F. Minimum Tillage

Thispracticeinvolvedthesowingorplantingofcropsinuncultivatedsoil.Thisisusuallypracticedinslop-ingareaswhereinitwouldbeverydifficulttousefarmimplementsortractorincultivatingtheland.Inthispracticesurfacemulchorstubblecanberetainedinthesoilasgroundcover.

Thispracticereducesrun-offandstructuraldeclinebutenhancestheretentionoforganicresiduesbecausewithminimumtillage,lessorganicmatterisdestroyedduetolesscompactionofthesoil.Likewise,theplanresiduesareleftintheground,therebyprotectingthesoilagainstrun-offandconservingsoilmoisture.Italsoenhancessoilfertilityandhelpsmaintainoptimumsoiltemperature.

GrassesandstubbleuseassurfacemulchandgroundcoverintaroplantationinSavai’i,Samoa.

GrowingpineapplewithminimumtillageinUpolu,Samoa.

Ataroplantationappliedwithminimumtillageinoneofthevillages–AleisaonUpoluIsland,Samoa.


G. Fertility Maintenance/Organic Agriculture

Thekeyelementsoforganicagricultureproductionare very similar to the traditional farming systemthathasbeenpracticedinSamoaforcenturies.Or-ganic farming maintains biodiversity on the farmandusesmethodsthatsupportconservationofnat-uralresources.

Whenwesaytheproduceorproductisorganicallyproduced,itmeansanapprovedproductionsystemwasfollowedthatintegratescultural,biologicalandmechanical practices including the soil andwaterquality in its operation. Organic system does notuseanysyntheticfertilizersorchemicals.

Allproduction inputsare fromthenatural sourceslike leaf litter,grassclippingsandorganicmanure.Organicmatter is used to build andmaintain soil

fertility,improvethephysicalandchemicalproper-tiesofthesoilandgenerallytheoverallsoilhealthincludingthemicrobialactivity.Organicsystemen-couragesandcreatesanidealhabitatforbees,batsandbirds for pollination and their contribution tothegeneralbalanceofthenaturalecosystemwhichiscrucialtofoodandnutritionsecuritysustainableagricultureproduction.

Thispracticeusesorganicresiduesassourceoffer-tilizersforcropstominimizetheinputsofinorganicfertilizerswhichareusuallyveryexpensiveforthefarmerstobuyandusedintheirfarms.Thevillagecanalsoproducecompostandothersourcesofor-ganicfertilizerslikecoconuthusk,woodfiles,chick-enmanure,cattlemanureandothers.

PileofcompostreadytobeusedasorganicfertilizerinCook’sFarminUpolu,Samoa

DriedbananaleavesusedasfertilizerandmulchforbananainUpolu,Samoa.

Finelyshreddedcoconuthuskusedaspottingmediaandassourceoforganicfertilizer.

TheuseofcoconuthusksasfertilizerandpottingmediafororchidsinUpolu,Samoa.


H. Agroforestry

Agroforestryisanintensivelandmanagementsys-temthatoptimizesthebenefitsfromthebiologicalinteractionscreatedwhentrees/shrubsaredeliber-atelycombinedwithcropsand/oranimals.

Agroforestry systems provide environmental pro-tection, improve productivity and minimize theneedtousesyntheticinputslikefertilizersandher-bicides.UnderanAgroforestrysystemthenutrientrecyclingisenhancedandthereisgreateruptakeofsoilnutrientsbyplants.Treesapartfromprotectingcropsfromwinddamageincreasethe

Agroforestryisanintensivelandmanagementsys-temthatoptimizesthebenefitsfromthebiologicalinteractions created when trees/shrubs are delib-eratelycombinedwithcropsand/oranimals.Agro-forestrysystemsprovideenvironmentalprotection,improveproductivityandminimizetheneedtousesyntheticinputslikefertilizersandherbicides.

UnderanAgroforestrysystemthenutrientrecyclingisenhancedandthereisgreateruptakeofsoilnu-trientsbyplants.Treesapartfromprotectingcropsfromwinddamageincreasethe

ExamplesofAgroforestryareainUpolu,Samoa.

ExampleofAgroforestryareainSavaii,Samoa. AgroforestryasadoptedinApolimatai,Samoa.


I. Permaculture

Thetermpermaculture,meaning“permanentagri-culture”wascoinedinthe1970’sbyAustralianBillMollison. This refers to the concept of integratingplantsandanimalsinrelationtohumansettlements,mostly aimed towards household and communityself-reliance,andperhapsasa“commercialendeav-our”onlyarisingfromasurplusfromthesystem.

However,permaculturehascometomeanmorethanjustfoodsufficiencyinthehousehold.Self-reliancein food ismeaningless unless people have accessto land, information,andfinancial resources.So inrecentyearsithascometoencompassappropriatelegal and financial strategies, including strategiesfor land access, business structures, and regionalself-financing.Thiswayitisawholehumansystem.

Permaculture,then,isadesignsystemthatencom-passes both “permanent agriculture” and “perma-nentculture.”Itrecognizes,first,thatalllivingsys-temsareorganizedaroundenergyflows.Itteachespeople toanalyseexistingenergyflows (sun, rain,money, human energy) through such a system (agarden, a household, a business). Then it teachesthemtopositionandinterconnectalltheelementsinthesystem(whetherexistingordesired)inben-eficial relationship toeachotherand to thoseen-ergyflows.Whencorrectlydesignedsuchasystemwill, likeanaturalecosystem,becomeincreasinglydiverseandself-sustaining.

All permaculture design is based on three ethics:Careoftheearth(becausealllivingthingshavein-trinsicworth); careof thepeople; and reinvest allsurpluses,whether it is information,money, or la-bour,tosupportthefirsttwoethics.

Practicallyspeaking,asuccessfulpermaculturede-

signisbasedonthreeguidingprinciples.First,eachelementofthesystemperformsmultiplefunctions(for example, an orange tree in my yard suppliesfruit for food and a cash crop, rinds for compost,leavesformulch,deadtwigsforkindling,andshadeforme,mycatandotherplants).

Second,eachdesiredfunctionofthesystemissup-portedbymultiple elements (further shade inmyyard comes from an overhead trellis with grape-vinesandseveralnativetrees).

Finally, and crucial topermaculturedesign, every-thinginthesystemisinterconnectedtoeverythingelse. This is vital, because the susceptibility andoutputofasystemdependnotonthenumberofel-ementsitcontains,butratherhowmanyexchangestakeplacewithinthesystem(thinkofanoldgrowthforestvs.amonoculturetreefarm).

Actually permaculture has long been practiced inSamoa since when you visit each village you canfindthatineachhousehold,theyhaveagardenat-tachedtotheirhouse.ThewaySamoanstakecareoftheircropsisalsoverymuchrelatedtotheirculture.

A Samoan farmer with her plants surrounding her house in Savai’i, Samoa

A typical house in Manono tai, Samoa showing the harmony between the farmer’s house and the surrounding environment.

Another example of permaculture in Savai’i wherein the animals depend on the plants in the farm for food.


AnotherbeautifulexampleofPermacultureasexemplifiedinCoconutBeachClubResortandSpainthevillageofManinoa,Upoluisland,Samoa

AnexampleofpermacultureinManonosland,Samoa.

PermacultureasappliedinthescenicislandofApolimatai,Samoa.


J. Soil Erosion Control Measures

Erosionreferstothedetachmentofsoilorrocksbywind,water,iceandgravity.Theamountoferosionthatwilltakeplaceinanyareawilldependonthefollowing factors: a) steepness of slope; soil type;amount and type of surface cover; slope length;intensityandamountofrainfall;soilmoisturelev-elspriortospecificrainfallevents;andsoilsurfacecondition.Someofthesefactorscanbecontrolledwhileotherscannotbealteredoruncontrolled

Thedamagecausedbyerosioncaneitherbemin-imal or highly destructive as in the case of Guin-sauguninSouthernLeyte,Philippineswhichburiedalivethousandsofpeople.Thisisoneofthemajordisasters recorded in the Philippines concerningerosion.

This topic will focus on some important practicesandtechnologiesthatwillreduceorbreaktheslopelength to minimize the impact of erosion. Thesetechnologies include the construction of contourbarrierssuchascontourhedgerowsandbrushwoodstructures,terracing,contourditchesandbanks.

(a).ContourHedgerows.Thisreferstohedgerowsoflegumes,shrubsandgrassesgrownonthecontourbetweenarablecrops.Thiscanbeeasilyestablishedusingnaturalvegetation.Thealleysorspacesinbe-tweenthecontourhedgerowsareplantedtoannualcropsandhedgerowstrimmingsarelaidasmulchinthecroppedalleysbetweenthehedgerows.

Contour hedgerows technology will address soilerosionproblembyreducingthevelocityofrunoffandtrappingthesedimentsattheirbase.Likewise,theywillminimize thedownhillmovementof soilby shortening the slope length and by eventual-ly forming terraces as soil particles accumulate intheuphillside.Thispractice ishighlysuggestediftheslopeexceeds5%andthelandiscultivated.Inthiscontrolmeasure, it is important tocontrol theflowofwaterfromabovethehillorfield.Ifanotherfarmerownslandontheupslope,heshouldbeen-couraged todosoil conservationmeasureaswell.Check for theoccurrenceofdamsordiversionca-nalswhichmaybeneededtocontrolwatercomingfrom theaboveplotsor farms. If the farmerownsenoughland,itishighlysuggestedtoplanttreesatthetopofthefieldasshownintheexamplebelow(WorldAgroforestry,2016).

Choice of plant species for contour hedgerows:Inchoosingvariousplantspeciesforcontourhedgerows, it isrecommendedtotrythefollowingplantspecies: Flemingamacrophylla, Desmodiumren-zonii, Gliciridiasepium, Leucaenadiversifolia, Leu-caenaleucephala,Sennaspetabilisoracombinationofthesespecies.Itisalsorecommendedtocombineplant6speciesthatcomplementeachother.

For example; plant a row of Fleminga for leavesthat decompose slowly and provide mulch to becombined with a row of Leucaena for leaves thatdecompose slowly and provides nitrogen. Othernitrogen-fixing treessuchasAcacia,Sesbania,andCalliandraspeciesarealsousedashedgerows.

Example of contour hedgerows taken from Erosion lecture of A.B. Tulin, 2016.


Thistechnologyisfocusedonrestoringspecificerodedlandsorfarmswhichhinderfarmoperations.Spe-

cific low-cost technologiesareavailabletorepairdegradedorheavilyerodedsteep lands.Whilethese

technologies areusually capableof reducingor stabilizingdegradation, the complete rehabilitationof

severelyerodedlandsisaveryslowprocess.Thefollowingtechnologiesthatareworthtryinginrehabili-

tationprocessinclude:landsliprehabilitation;rehabilitationofseverelyerodedlands,gullystabilization

andstreambankstabilization.

Thistechnologyinvolvedacompletecontrolstrategyutilizingarangeofcomplementarypestcontrolmeth-odsinamutuallyenhancingandsustainablefashion.Itcombinesseveralpestcontrolstrategiesincludingbiological,culturalandchemicalcontrols,andvarietalresistance.IPMisappliedtoinsectandmites,weeds,nematodes,anddiseases.

Rehabilitation of sea shores by sea bank stabilization in Upolu Island, Samoa.

Insect traps in bottle with pheromone as a biological control in Upolu Island.

K. Rehabilitation

L. Integrated Pest Management


Thistechnologyreferstothepracticeofinterceptingwatertominimizesoilerosionandconservewater.Thisisachievedbyestablishingphysicalstructuresorvegetativebarriersthatslowsurfacerunoff,increaseinfiltration,anddivertexcesswatertostoragefacilities(SEARCA,1998).

OneofthemajorproblemsincropproductioninSamoaistheverylimitedwatersupplyespeciallyinele-vatedareasorinmountainousareas.Throughoutoursurveysinthefourislands,wehaveobservedvariousindigenousandpracticalwaysofwater storingandharvesting. Theassistanceofour fundingagenciessuchasAusAid,EuropeanUnion,ChineseEmbassy,RedCross,USAID,UNDPandotherhavehelpedalotinstoringandconservingwaterinSamoa.BelowaresomepicturesofwatermanagementinthefourmajorislandsofSamoa.

M. Water Management.

Example of planting trees along contour lines in Upolu Island, Samoa

The use of cement tank and steel tank are used in storing water in highland areas of Upolu Island, Samoa. The steel tank in green was donated by Australian Aid; European Union and CSSP.

The use of cement tank and steel tank are used in storing water in highland areas of Upolu Island, Samoa. The steel tank in green was donated by Australian Aid; European Union and CSSP.


Different ways of collecting rain water in Apolima tai, Samoa.

Rain water collection in Manono tai, Samoa.

An indigenous way of storing water in one of the villages of Manono tai, Samoa.


Conclusion

This report features the various activities as out-linedinthetermsofreferencefortheconsultancywork.WeareindeedsohappyforUNDPandMNREforgivingus thisbeautifulopportunity to interactwiththevariousstakeholdersengagedinagricultureandsomesoilconservationactivitieshereinSamoa.ThetriptoSavai’iwasverymemorablesinceitgaveus the chance to interact with some farmers here in Samoa and to observe their various crop produc-tionpractices.Ourvisitwasalsohighlyworthwhilesince during our visit to the island of Savai’i, wehaveobservedthaterosionisstillnotaveryseriousproblemhere inSamoa.WealsodiscoveredaboutthereforestationactivitiesdonebytheMinistryofNaturalResourcesandDevelopmentespeciallytheDepartmentofForestry in theirmassive reforesta-tionactivitiesinSavai’iwhichisgreatlyresponsiblefortheverythickforeststhatisnowdominatingthewholeisland.Duringourfarmvisits,wediscoveredtheimportantrolesthatwomenplayedinmanagingthefarmespecially incaseswhere inthehusbandisabsentsincetheyareeitherworkinginUpoluoroverseas.Furthermore,wefoundoutthatthetradi-tionallandtenuresystemisalsoverybeneficialtoSamoasinceitgaveenoughlandforthepeopleinthevillagestocultivate.Thatiswhy, it isveryevi-dentduringoursurveythatmostofthehouseholdsinthevillageswevisitedhadapatchesoflandfortaro,bananaandbreadfruitwhichthinkthataslongas theyhave these three crops in their ownback-yards,theyareconfidentthattheycansurvivedandcanprovide food in their tables. Lastly, it isworthnotingtoseethebeautiful landscapesthroughoutoursurvey.WhatisadmirablethoughistheuseofvolcanicsoilsforagricultureinSavai’i.Thispracticeisreallyhighlycommendablesincethepeoplewerestillabletogrowcropsinthistypeofvolcanicsoilswhichareinfertileandhaveveryshallowtopsoils.

From the results of our participatory assessmentsurveyswiththefarmers,wenotedthattheylackedinformationonthelatesttechnologyinagricultureandmostofthemreliedonlyontheskillsthatwerehanded down to them by their parents and fore-fathers.This is something for theMinistryofAgri-culture andMinistry ofNatural Resources and En-vironment to consider.We think that there shouldbesincereeffortstoreachouttothefarmerssincetheyaretheprimaryproducersofthevariousstaplefoodssuchastaro,breadfruits,coconutsandbanana

thatthemajorityoftheSamoanpopulationisrely-ingon.AneffectiveextensioncumtrainingactivitiesshouldbedevelopedfortheSavai’ifarmerstohelpthemimprovetheircropproductionpracticessothatitwouldalsobecomemoresustainableintheenvi-ronmentinthelongrun.Someofthefarmersalsorelied on chemicals to eliminate pests andweedsbuttheyfoundittobeveryexpensiveforthemtouse.Mostofthefarmersdon’tapplyfertilizersandbecauseofthis,thus,technologyonorganicfarmingshouldbedisseminatedtothem.Likewise,theuseofintegratedpestmanagementandbiologicalcon-trolshouldbeproperlydisseminatedtothefarmerssothattheycanpracticetheseintheirownfarms.Wearealsogladthatwediscoveredthatsomepro-gressivecommercialfarmersliketheownersofMa-laefonoOrganicFarmsinUpoluarealreadyadopt-ingorganicfarmingtechnology.

We also learned from the results of our soil chem-ical analyses that indeed the soils of Savai’i haveverylowamountsofexchangeablePandotherba-siccaptionswhichcouldbeattributedtothevolca-nicnatureofmostof thesoils inSavai’i.Howevertheuseoforganicresiduesascovercropandsourceof fertilizerswhich is very common in Savai’i alsoincreasedtheamountsoforganiccarbonandtotalNinthesoilassupportedbytheresultsofthesoilanalysis.

In the drafting of the Soil Conservation and LandManagementManualforSamoa,weincludedthosetechnologieswhichwefoundwerealreadypracticedbysomefarmershereinSamoa.Thistechniquewillthenbeeasyfortheotherfarmerstofollowanddointheirownfarms.Weoutlined11soilconservationpracticeswhichareeasytofollowandcanbeusedhereinSamoawhensomesignsoflanddegradationanderosionstartappearinginthefarms.

Lastly,wesuggestthatwewillstillvisitsomefarmshere in Upolu Island aside from the ones like theCook’s Farm inSaleimoawhichwealreadyvisitedtointerviewadditionaltraditionalfarmersandpro-gressive farmers here in Upolu Island, Samoa.WeplantointegratethefinaloutputsinUpoluwiththeonesthatwefoundoutinSavai’itohaveaholisticviewof thecropproductionsystemsandsoilcon-servationpracticesinthewholecountry.


Recommendations

Fromtheresultsofthisconsultancy,wewouldliketorecommendtwothingsthatneedtobepursuedasanimportantoffshootoftheproject.

a.Thereisaneedtoestablishamodelfarmfeaturinganintegratedandholisticapproachtolandmanage-mentandsoilconservationwhichshouldbeestablishedattheIRETAFarm,SchoolofAgricultureandFoodTechnologyinAlafua,whichwillservetoshowcasethevarioussoilconservationmeasuresandtechnol-ogiesthatwesuggestedinthisreport.ThiswillalsoserveasalaboratoryforstudentsatUSPtakingSoilScienceandCropManagementcourses.ItisworthmentioningthetopiconsoilconservationhasalreadybeentaughtatUSPAlafuatotrainfutureleaderstobeourpartnersintheseinitiativessothattheimpactofthisprojectwillbecomesustainableandpartofthenationwideenvironmentalprotectionprogram.

b.WerecommenddevelopingaprojectonorganicagriculturethatwillbefocusedonthedevelopmentofbiofertilizersandbiopesticidesthatwecanuseinimprovingcropproductionhereinSamoa.ThisprojectwillbecoveredinstrongcollaborationwithdevelopedagricultureuniversitiesinAsiawhichhaveastrongprogramonsustainableagriculture.

c. It is further recommendedtohaveacontinuousprogramwithMNREandMAFF in the trainingofourfarmersandstakeholdersinsoilconservationandmanagementusingthismanualandtheaccompanyingvideos/audiovisualmaterialstoclearlyexplaintoourfarmerstheproperconceptsoutlinedinthismanual.


Acknowledgement

Wewouldliketoacknowledgethefollowinginstitutionandindividualswhohaveassistedusinmakingthismanual:

• TheUniversityofSouthPacificSchoolofAgricultureandFoodTechnology• ThestaffoftheMinistryofNaturalResourcesandEnvironmentofSamoa• UnitedNationsDevelopmentProgram• ThestaffoftheSoilScienceDepartment,SAFT• ThestaffofIRETA,USP• Thefarmersthatwehaveinterviewedduringoursurveys• Thevariousstakeholderswhoattendedthestakeholder’smeeting


References

Cramb,R.A.2000.SoilconservationTechnologiesforSmallholderFarmingsystemsinthePhilippineUp-lands–aSocioeconomicEvaluation.ACIARMonographNo.78,228p.

Hartemink,A.E.,McBratney,A.B.,andWhite,R.E.2009.SoilScience.VolumeIII.SoilUseandManage-ment.Earthscan,UK,328p.

Lal,R.1981.Managementofthesoilsforcontinuousproduction:Controllingerosionandmaintainingphysicalcondition.inD.J.Greenland(Ed.).

manual of soil management and land conservation in samoa€¦ · land-management approach to soil...

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