Expansion of crop diversification in paddy fields through new irrigation technology and the change of Bethma custom in Sri Lanka
その他(別言語等)
のタイトル
灌漑技術の普及がもたらす農村制度の変容 : スリ ランカの水利慣行ベトマの事例
著者(英) Kono Hiroichi, Somarathna Hetti Mudiyanselage journal or
publication title
Research bulletin of Obihiro University.
Natural science
volume 21
number 4
page range 75‑84
year 2000‑06‑30
URL http://id.nii.ac.jp/1588/00001866/
滞人初戦21(2000):75〜84
7r,潅漑技術の普及がもたらす農村制度の変容 スリランカの水利慣行ベトマの事例
耕野柘一1、HettiMudiyanselageSOMARATHNA2
(一受理:2000叶3月17口)
ExpansionofCropDiversi五cationinPaddyFieldsthroughNewTrrigationTechnologyand
theChangeofBethmaCustomi11SriLankn HiroichiKONOl,HettiMudiyarlSelageSOMARATHNA2
鯖 雲
スリランカの稲作生産は、「縁の革命」の経験により19脚年代の半ばにほぼ自給水準を達 成するが.その後は濯漑開発の経済的適地の減少による水資源の効率的利用等が問題とな
ってきている。このため、限られた土地からの農業所得向上と水資源の効率的利用のため、
乾季における水分要求量の少尉、米以外作物の導入が課題となっている。
以⊥のような問題意識の下で、1997年、19g8年にスリランカのドライゾーンで農家実態 調査を行った。調査地城では199岬・代以降、ポンプ潅漑の導人が急速に進み、乾季にはト ウガラシ、タマネギ等の作付が吋能となったっ この研究の目的は、第1に水が希少資源であ
る地域において、ポンプ濯漑技術が乾季の水田農業多様化へ与′えるインパクトを計量的に 把握すること、第2に、ポンプ濯漑技術がもたらす村の伝統的水利慣行の変育と今後の課題
を明らかにすることにある。得られた結論は次の2点である。第1に,ポンプ所有による水
利用可能件の拡人は、強く乾季の水田農業多様化を進展させていることがトーピットモデ ルにより確認された。第2に、個別的水利用を可能とさせる港漑技術の普及はスリランカの
伝統的水利熔行ベトマの変容を伴うものであったu水をめぐる政府と農民の新たな協力体 制作りが緊急の課題であろう。
キーワード:氷山農業多様化,ポンプ漸乳ベトマ
1.hbot7Ltf)ryOrA軒imltura71hsoureeEconoTrLic§,DepartmtlntO[ATlimalPrbduct50r[andAかcl]l如ra]EcoI10mics,
ObibjroUlliversjけandVeLerin即γMdidTle,Objhiro,Hokk扇doO80j555,Japan 2.F血ultyofAgncu]hlltL,UI血ersityofPelⅥdeniya,SrlIAnh
l.帯広畜産人学畜産管理学科畜産資源経済学講座(0弧8555 北海道帯広巾稲田町)
2.ベラデニア人学農業部(スリランカ)
耕野拓一
■. ti
1.1NTROIIUCTION
Developirlg COurltfiesinAsia have experienced 伽eGf飴mReⅥ)tutiona丑dasa(OnSequenCealmost al1thesecountneshavcattainednearselflSt戯cieney inrice producLlOn,and at presenlsome ofthese nationsarefaeedwiththeproblemof$urplusindce production(Masuda15冊)_′me代ぬ代,也ereisaneed tcrincrease the cultivatioIlOf other 丘eld crops
(OFCs)in order to soIvethe problem ofbudget burden reslllthg 加m the su叩1us dα_
Furtherrnore,OFCsneedtohavemorewidespread useofteehnologicallyadvancedequipmentandllaVe toe舶blislle穐cientmarkedngdlannels,劇紳,】訓d 那扇】able fnr f・COnけmically viablei汀iga加n
developmenthasbeefLdecreasinginAsiancountnes as shownin the Klkuchijnvestigation,Trngation developments have shi触d打om the■coflStruCtion st噌e一拍血e†mana酢mel止絨age†耶ikuchi壬2り.As
su(:hitisnowimpo化mttoぬ亡uSOmthee代ciemtuse ofimgationwater,¶liscropdhTerSincatior)(Cl))is nowconslderedto be a good sb・ategythatean be used tot且Ckle Lheproblcm弓thathaNeCmergedin thePo淡−Gfeenkvol11tionperlOd.1t helpstoreduce the amo11ntforelgn eXCllange11Sed toimportfood amd caIleam fore鹿n exchaI唱e through exp)止
promotior[,Moreover,CDis expected toincileaSe 仇eaverageincomeofhm血1g血milleS.
F11ndamentaleconomiedl珊geS klduced by the GreenRevolu血narerelevantinSriL揖1katoday.In SrlIム11ka there are two clima血・regic)mS:the wet zoncandthedryzo[氾.Inthedryzone,ricefamling hasbeenpracticedoYeralongpedod8ftuneusimg bo仇tanksandimgationc弧als.¶leSeCan扇5Were o吻albr con或meted by an anclent dynasty more tbana仙ou組ndyea指agQ.Idgationschemesintk COunbYean be dividedinto two types;SmallTSCale andlarge−SCale.A smallrscaleifrigation seheme prnddesl汀転出iom watertole5S山卸200a汀eSOf 血mland while al訂ge−SCalei汀短ad8n 託beme irriEateS mOrethan200acres ofland,A鮎rWorld WzLrIImanyland settlemellt Sehemes were developed umder山esela曙einうg如l−)n SCllemeS・
Today,this system providesirrigadon facilities to about6O%ofthetotalirrigablelandinthecountry and.there払re,is responsible for a hi感Ier percentage oLIlationalrlCe prOduction.nle dry 2;One,Whichcoverstwo−thirdsoftheco11nbv,hasan uneveIldistdbution of rainhll.During the A地 season(wetseason)&omNovemberto M打Chthe dryzoneaveragesaboutl,1OOmm ofrainh)mthe n()Ⅰ寸h・モaStlllOnSOOn.恥wever,during the 乃点 Sea貝nn(dry season),Whiehlasts fぬ1n Mardlb 艶ptember,it gets only abour200mm of raiI血Il 加m tlleSOuth−WeStmOnSOOn.¶加rc丘■代,也en10St Cr竜tica】rest)urCeiれ仙e dⅣZOneis′Water∴げ廿肥化 Were nO additior[alwater supply d11血g the Yala SeaSOnitwollld be dif6cult to cultivateany crops.
UElderthese circumstances暮he promotion ofcrop
〔liver5通(二atiollisimpoぬnttoiI忙reaSe払rmiJICOme 打om alil両睦dland area and to use exISting irrigation faeilide$ e借ecdvely through the introduc伽nofOFCswhichdemandlesswaterthan
再ce(Wijera仙na(オ〟 川).The objecdve of血s s山dyis toidenti知Cl)
possibilitleSinSriLAnkaIshrgei汁ig釦ionschemes.
ThisstudyisbasedonasulYeyCamedoutin1997
tol!柑8,In仙estudyarea,thegove汀Inlentismain】y responsible forirrigation management.Fmers もegan ushg山eir own smallimga也on pumps to cultivate OFCs h paddy Belds duringthe YaIa SeaSOn aftcr1990and as aresult CI〕iIlthe study
∬eよhaspro訂eS鑓dwell.hgヒneralitis匹htedo11t that there are many restrictions to CD,SllCh as marketprice仙1C山adons,higber】ab()rrequirements 仏祖inpaddycu摘vationandh軸潔丑】1ity(lfexis山Ig
irngation mallagement_1nthispar絶rWeattemi)ttO
discover ptlLenlialof CD wlth spccialrcLerence to
watermam覗ement, merearflt酬mair10bie亡tivesbf
tlleStudy:idendfytheimpactofpumpirriga山)nOn
CDinthedryzone,Wherewateristhe伽StSCarC
resource,and exa血e山e chamges of t指d班onal
waterInanagement CUSt(imSirlput〉liciけi関山on
SChemes due to tbeimけoduction of mewl汀短a怯on
technology匝ump皿丁短慮ion).
hpansionofCropDiversjficatiDn
anothersurveywasconductcdinAugust1998witll the same farmersIo collect data relatc(1to Lall(l 血11izatiom and waterlllallage†¶e11†in Malla for
1997/98and Yala cl11tivationin199Ei.Although60 farmersweresurveyed,datarehtedtobothseasons
COuldbecollectedh.omonly50farmers.nere血re,
thedatafrom50farmerswereusedintheanalysis.
1n the study sample there were th].ee hndless Larmers aTld47famers who werelandowllerS Or owller−tCnant farmers.′111ere Were eIght farlllerS who had two−Whec]tractors while two tarmers had hur−WhetIllractors.Mostofthesefarmersrenttheir lractorsIo oLhcr farm(・rS.111Cre Were17farners who owned cattle and they also rented out tbeir cattlぐtO Otllerfamersfor cultlVationw(汀k sucllaS lan(lpreparatlOnandthreslling.
3.TIIEPROGRESSOFCROPDIVRRSIFICATI()N ANDI)IFFU5;ION OF NRW AGlモICUI」TlTRAl.
TECHNOLOGY
′11ablcIshows 血e generalsituation of the surveyedfarmers,Duringthewetseasonalmostal1 farmers cultivated rice and only a few farmerS cultivated ehilis and onionsinaddition to nce.ne average cultivated area was2.97acres duIlng the Maba seasonin1996/97and was2.58acresin the MahaseasoIlin1997/98.1)I111997Yalaseasoll,28 LamlerSWt・reCu]tlVatlngaJldo(themonly17famers CulllVatedoIlionswhilesomt・hrTnerSCultivatedrice,
chi】is,pUmPkjmsandbeets.2)′】llenumberoffanrLerS
(14)who亡ultivater]1essthan O.5acreswashigher.
The average cultivated areawas O.58acres and22 farmersdidnotcultlVateanyCrOPSatal1.1nthe1998 Yala season35farrners cultivated.The number of farmers who cultivated more than two crops increased.During this season the majoritv of the fanTlerS(26famers)cdtivaLcd O.51−2.5acres.The averageareacultivatedinthisseasonwasl_2acres anditwasmorethantwicethanthatofthe1997Yala seas(〕】1.TllenUmberoffarmerswhodi(1IlOtC111LIVall、
anyeropsdecreasedto15hrmers_
2.GENERALINFORMAT10NOFSTUDYAREA
rhe Al1111nugamavi1lagp h MahaweliSystem fl wasseLectedforthestudv.TheMahaweliSystemH was the琉rst area developed under the MahawIIll T)evelopmentProjectin1977anditwasdividedinto 7blocks.Each bloぐk was again sub−(livi(LedilltO severalllnits.Today,eaehblockandunithasablock managerandal上nitmanager.respectivelyandLhcre arebl(lCk()用亡eSalld unit〔〉fRcesateachlocation.
R&1Stl」dyA代a
OllrStudyv】11ageislocatedintheHelabodugama Unit of the Galnewa Block.The Galnewa BIot二kis supplicd wiLhimgatlOnWatCrbythe Kalawewalef[
bank mai】l CanaL whkhis corLneCted to the Kalawewa tank.Amunugal11a getSirrigation water fromthelくalawewalef[ballkcana]throughtheNo.1 distributory cal】aJ(Fig.1),The pllblicly run
Mahaweliuconomic Agcncy(Ml三A)has the rビSpOl】Sibility ormanagi噌LbeirngallOIliIISyst(1Ill H,Il汀仏inlalnSthemalnCamalsandllledisしhbtll(汀y canals,therefore,imgatio】lmallagenlel】tin the vi11ageis done nlainly by the goveT nl11ent_Farmer particlpationinirrigation managementislimited to the field canallevel.Thel−e are nine 丘eld canal groups in Amunugama village and each group eonsists oflO to13 farmers wllO CO】1ectively maiI】tairL LtlCimgaLioIICanals of Lhc vi11EIge.The numbel■Of farmers j】1t】le VillagpislⅢ(August 199即.Forlhc present s山dy 60 famers were Selected ralldolmly andiJIAu即Sl1997 a soぐio−
economicsurveywascanうedoutwiththesefarmel−S
to collect data related to cultivationin Mahain
1996/97an(JYala cultivatiollill1997.】n a(]dition,
朝野播
Tabl8.1ThoNumbor ofF●rmOr■bvFamSi王○されdCroロPinEP鵬m9
Cr叩PingP如触椚Ⅶ ニー こ 二 二 …・ こ ・ こ Fmsiヱ○(○¢rO)in1997乃8M山鳩
・−8.5 0.5T
一一乙5 ■−2.5
{ 88 8 口 42 4(】 口 3 44
H+Gi 4 口 ロ q 7
「け8thoronoqrob 0 4 4
n十ci+pI( 0
Tぬl 0 嶋 ヰ 2 口 50 ○ 45 口 3 0 4g
…● 二 ■=− l F■m8iz8【8erO)in柑97Ya18 F削¶=琉H(さ¢rl〉)in1998Y自由
・−0.5 ○,引
■−2.5 ■−2.5
l「 4 4 q 5 8
On 13 4 17 4 4
bo 0 2 3 5
Dk 口
H十oth●rOnOCrOロ 2 2
αT+○廿lOrく〉nO¢rOD 山 8 4 2 4 6
bo十○廿lOrOnO¢mD 0 2 2
亡卜to◆血
0bo+¶柑−トDk 0
r汁on+othorono(汁」】D 5 5
0∩州山8rthr朋CmD8 0 3 3
T山l 1ヰ t3 口 8 0 28 9 26 0 0 0 35
りパ:血0.On:On加.b0. :h鴎Ci:Chilli.m旧:m8iz8.也加m水0.Pk:PUmPk事n
2〉−○机8r GrOp i8m州y卵即Fam.COWp88in8dd帖onto廿帽OmPSinl).
8)柑97/98Maha.ono血morgaⅧh;石l8ndt8anO廿柑rfamor8S8bn抑tandwe¢OUldn tg虎iポom虞i8nrel血dto cropcu愉/8日on.BOt血」numboroff8m8帽i8ヰ9
A c)ear difFerencein cropping patternS WaS Observed during the1997and1998Yala seasons。
nerewere two reasoms Eor thisdiffcrence,First.a dropin the pnce of onions h om30rupeeS Per kilo訂min1996to23rupeesperkllo卯r11im1997 decreased thc number of farmers who culdvated onioms.ne amo11nt Ofwatcrin1998Maha seasoJI wasfarmorethan1997Mahaseasonandtherewere
alotofwaterin仙ebeginningofYalaseason199乱 Consequent)y the average cultivated area became morethant雨ceandthenumberoffamersgivemup farmingwasdecreased.Ashasbeemdiseussed,itis mlpOrtarLttOCOmplementthedryYblaseasonwith
the abundance of water fromthe previous Maha seas()n_neCOnStmCtionoflargei汀1galionschemes ismaimlybrculLIVatlOnd11ringtheMahaseasonand itistherefL)re hnpossibleto cultivate allthepaddy 負eldsinthe Yala season(Ⅲkuchi[3L).nle paddy croppingintensityir)Yala season was about60%
(Kono14】).
Amunugamavinagt:adopted the pumplTTIgatiorl systemin1990.勒1997,20famershad仇eirown pumps wllile19faJ・merS OWned agrowells,Thert・
were13hrmerswhohadbothpumpsandagrowells.
nlereaSO11forlherapidadoptiomofIlewirrigation technologywasthathrmers quickly respondedto the highpro丘tability of crops such as chilis and oniollS Which demandless water(Kkuchi,1993).
Famersinthevi11agegenerally11Seda5−hpportahle Water pumP.It was found that19血mers,Who owTled water pumps got water from their owIl agTOWellsinthe1997YalaseasoTl,Theseagrowells wereabout3metersindiameterandhadadepthof
7meters.FamersusedlOcmdiameterpiI㌍tOpump water up丘・Omthe agrowe]Ts.There wefe three Larmers who gotirngatiollWater fromirdgadon canals and bur 血TmerS Who got water 血■Om dr訓nageCam山s.However,血euseofdrainage飴n山 Waterisillegalin血eareaandabuscrsaresubjectto
hes.1t was found,though,that fmers were unwi11ing tn fonow也ese regulati()nS.Fu血eml(〉陀,
therewereanotherIQurfarmerswhopumpedwater
山〕m the Kala Oya RIVer and cultivated o】lbo也
banks,WI厄chisalsoprobibited.
ExpansionofCropDiversiBcation
79de匹ndentvanableis uniq11ely representedin the bllowimgexpressiom.
Y干=Ⅹ/?十u.i=1、2、−、n
T?bl01ThBNunborofF−mOr8J)yPurTIF.Ow.即ShipandOulヒiv8tFon
¢∪帖v一也 NoCuI【ん8t8 Tobl T997 Y8b OwnPumb 18(13) 2【0) 20(13) NoPum8 10(5) 20〔1) 30(6) Tぬl 28(柑) 22(り 50(1g〉 1898 YさIa OmPum【l か町ほ〉 ∝0) 24(1ら) NoPum【】 11(6) †5【0) 26(6) Tot8l 35αり 15(○) 5叱り 1)Fi即r88inparo仙050SarO仇8nUmboroffさmIOrSWh。hav。
a訂OWell. Y=( †Table2shows血ereladonsllipbetweenwhoowns irrigationtechnologyandwhocllltivatedintheYala season.Table2shows thatfarmers cullivated thcir tandduringtheYalaseasonin19970fwhich18had their own water pumps and13 farmers owTled agrowe11s.There wel ̄elO farmers who cultlVated Without pumps alld 丘ve of these hadtheir own agrowe]1s_In the1998 Yala season 35 farmers eultivated,24hadownedwaterpumpsand15owned agTOWells.nere werellfarmerS Who cultユVatCd wi1hout pumps but6of them had agrowel】s.′111e rentalcost ofwaterpumpsperseasonvarled B Om
l,000tcL4,000rupeeS.Normal1yfarmersrentwater PumpS h ̄Om their relatives and neighbors.In
SUmmarY,Tab】e2clearlyshowsthatwatersupplyin the dry,Yda seasolldrastiea11y nuctuatesinlarge irrigatlOIISChemes.nerefore,the availabillty Of puInpSandagrowe】1sinAuencesthcprogrcs50fCl)
inpaddyfields.
1)¶1ereWaSnluCh rrLOrerain than usualseasoni]]
1997/98MallaSeaSOn.′ⅠもatisoIlerCaSO11forthe differerLCeOfaveragccultivaLlOnareabetween l!柑6/97Mahaand1997/98Maha.
2)Pro舟bbilib,OfchillSandonionsarcmorcthan twieeandeigllttlmeSaShighasrice.rcspectively,
mcy are called high performance crops inSri knka.
4.DETl王仙ImANTS OF CR()PDIVERSIFICATtON INmDDYFIELl)S
Now we willal】a】yzethe determinants of Cl)
progress by using theTobit modet.rlllis mo(1elis difkrent from other regression models as the
WheredleXistheexplanatoryvanable,rlisthe sample size anduiis aI10mlaldistri1〕utlOfLwith meanOandvarlamCeJ2.
Tobit modelestlmatCS maXimiz(Ldlog−1ikelhood Lunct10nbyusingthc datarclatcd to hrmerswho cultivatedanddldnotcultivateintheYalaseason.Il isasfD1lows;
lnL=h(p(−Ⅹ\′ゴ/J)
+志井刷肺−Ⅹ\わ/♂]−1nげ1
Wherc4and¢are,thedensityftmctionandtIIe distribution function of血e standard nomlal,
respeclively.
Thedependantv且tiableswerethecultivated area andthenumberofcropscultivatedr]uringtheYala SeaSOn becauseitis needed to血dtheimpact of thesetwoaspectsomCD.Table3showsthedetalls Of111C Vanabl(・S and Table4gives山e es也爪ated res111ts.Fromtheseresults,theLollowlngpOintscan becoI戒n11ed.First,intbe1977Yalaseasom,pump dummyincI easedinboth山ecultivatedareaandthe
numbtlr Of erops cultivated.This was statistically Signifie&nttOthel%level.Second,agrOWelldummy also had a signi五⊂ant(1%level)efEect on the progressofCD,buttheeffectwasnotasstrongas Pump d11mmy.¶由d,Ca仕1e d11mmy a蝕ded山e Cultivated areaandthenumberoLcrops cu]tivated.
Fourth.farm1aborers significant】yin8uenced the areacultlVated,and the age ofthe farmerafFected the number of crops eultlVated_Thesei]1月uences WerenOtaSStrOngaSthoseofthepumpdurnmy.In
Lhc1998Yalaseason.thepump dummyWaSfound tobethemostimporlanLEactorinfluencingboththe
−11−
耕野柘一
80
beginnmg of仇e1998Yila season.As a result,
EarmerS didI10t need to use agrowe11s as much.
Fur血ermore,the educatio月dummyinfhenced仇e progre5SOfCDsigniAcantlytothel〔悦Ievel
FromtheresultsgiveninTable4,WeCaneXplain the hnpact ofpump ownership ollCD statistically usingtheぬ川owlrlgequadons二
cultivatedweaand thenumberofcropscultlVated.
Agrowelldummy alsoinflueneed CD sigrlificantly.
H()WeVer,theinduencewasnotas如OngaSSbown bythepumpdtlmmy,inthe1997Yalaseason.This isbecausein血e1997/1998Mahaseasontherewas mbre raihLa11in the area than usualand alarge amo11nt Of water remamedim 血e tanks 誠 也e
T8blo,3 hdopondontVさ伽bl朗=胸紗dhT由比M8d0l
v01j8blo$ Do向】裾0れ
F8日¶L8bor
Thenumberoff3rmJaborseachhou$ehold
00fH朗d Ag更㌦hoadoさ¢hhウリ8鵬○!d
Ed此鵬8nDummy 】fh軸dfim●r卵duぬddn毎prim那YS¢h00l,仇ondumrny租
】一点望山越E没蝮仇8nlunorhis¢h00ら廿帽ndumm巴1・
PumpDuml叩 Ⅳ向morhさ8也oirownpump.廿帽ndumm戸1 肝n(〉 thondumm−
AgrowellDummy Ⅳ向mo「h8も仇oir(〉Wn8訂OW01l.廿帽ndummy=1.
肝n thondumm−
8a甜¢Dummy 肝向rmorhさS仇oi「own¢8恍Ie.仙endummy=1.
肝not廿帽ndul¶mV=8.
T曲l●ヰEs心内Jbd R●8u比¢rTobitModel
相田Y■la 柑g8Yさlき
v81i8bl8
¢u帖v一也darod NumborofGrOD号 ¢ul伽bdさ帽8 Numborof¢r01】S
¢ons也nt −0.¢24(−0.伽9) −1.陀2(−1.592〉■ −0.g88卜1.17更) −2.丁26ト†.引4)*
F∂mbbor 0.2008(1.76g)巾l 0.157(1.248)
一旬.004(−0.037〉 −0.043(一丑26幻Ag00fH朋d 0.00083(0.∝lむ
0.019(1.311〉 * 0.085(0.ヰ72) 0.021(1,182)Edu¢8心onDuMmy −0.811(一1.173) −0.444(一句.7即) 0.726(1.315)* 1.115(1.311)*
PumpDummy lll; l■; ・ 0.981(2,訓打)** 0.817(8.158)*** 1.459(3.598)榊
A伊℃W竃州Dummy 0.841(ヱ月71;)** 0.878(2.7耶)*陣 0.557(2.101〉 ** 0.688(1.柏7〉 * C劇oDummv
0.さ86(l.さ04)ヰ 0、47丁(1.542)* 0.117(D.46ヰ〉 0.325く0.引丁)」叫.59 −48.78
一引.53
−67.52∫J 1)F如roもInp且W仇○占●S8帽丁一∨扇∪88.
之〉*岬.♯.*8rO血t融施鵬=地相恥如t8tl%.5%.柑%.ro印さ成∨01y
3)w●両○虎鵬nu h叩血8曲水ono%lov0l.H¢:関帽mOtO柑0仇erth8nCOn8bntten¶=0
4)sさmPlosi王台=50.Thble5.
Fromtheviewpointofcultivatedarea,theprobability tocultivallコinthel淡)7Yalaseas()nWaS39,6%inthe case ofnon−pump OWning LafrherS.′rhe expected va)ue of the cultivated area was O.57acre3.If this 血Ⅶerhad a pump,山e probabili吋b cultiⅥ江eiれ Yala seasnn would hcrease to 80.6% and the expected value of仙e cultivated area would also
increasestoO,97acres.FromtheseresuJtsitisdear thalLheintroductlOn Of a pump increased the
possibility ofYa]a cultivation by41%dlle tO the expansiQn Of water av通えbility.ne expected c山也vation areaincreasesbyO.4acres.Inthe1998
P(Y†>0)=中伏ノ9/♂)
EⅣY∃>0)=X′ウ+♂・AⅨ・/ヨ/げ)
whe代 人∝;/ヲ/打)=≠(Ⅹこノヲ/け)/¢伍:β/げ)
1nordertoe$dmatetheimpactofpump.dummyon CD,WeaSS11medthata11variablesottlerthanpumps were set at卸erage Values.U A氏er血at we could compBLre the prりbabilltyofcultlVatioIlin the Yah season between Larmers who owned p11mpS and thosewhodidnot.Furthermore,WeCOuldesdmate the expected cu)tivated area and the number of cropscultivatedbyp11mPOwning血rmersandnon−
pump ownhg払fmers.Tもe res山b are givellill
ExpansionofCropDiversi丘utiu11
imigatlOn SyStemS by the govemmt・IIL Sincewateravailabilityis11nCertairldurlng the Yala season even with more
SOphistieatedirrigadon schemes
(Moragoda f】/〟F■l).1n th亡 Be血ma sysIcm,111elandtobccllltivatcdisusually closc to tlleirngatiollCanals becallSe thfl TabIe5.hlEIaCtforCropD;vers汁icatiorlOfPumDrrT・iEatJOrl
Cu帽v8tedAre8 NumberofCrot】g Est;mabd ErpeGbd Estin18tt〉d E〉【POet8d Prob8b捕tv Valuo Prob8bilitv V白山○
1997 39.6 0.57 45.0 0.69
Yala 80.6 0.97 83.6 T.15
T998 8T.3 0.71 59.3 1.09
Yala 90.8 1.19 92.2 1.94
wateris more easily accessible.Fmcrs withlELnd near the(_analhave to share theirlandwith othcr・
famlerS When Bethma cultivatlOnis done.In other words there are two famlergrOupS uI】der Betllma 仁一lStOm.■Hostねmers−由veha止of山血1andtu(1tllCT ねmers,and■Guest famers■arei】1V】ted by H()St farmCrStOCu】tivateapartoftheliostfarrner■slaJld
(Ekanayake efd.1H】).I.and aLlocationvia13etllrna cultivationis decided ala KaIIIla meetlngl)where faJ.mel ̄S,Unit OfBce o伍cials and BIock Omce Ofncials particlpate.The crops to be cultlVated are aIsodeddedatthismeeting,Imgatiomwaterjsthen distributedlo BctllInalaIlds(・nly. 111e reSt Ofthe land doesnotreceiveirrigationwater,Thel弓ethma areachangesyearaiteryear,therehre,therightto Cultivate Bethnlalandis】imited to only one pa而cularseason.
′111eprimeiplcoLcquali【yil)Walcrusageaccording to Bethma cuslom has almDst cullapsed in
Amunugamavillage.ThisismainlyduetotherecerLt adoptionofnewimgationteclm0logyIrlAmunugama village.farmers practLCed Bethma methodsinthe 1997 aTld1998 Yala seasons.Table 6 shows the relatlOnShip bctween Yala cultlVaし1t)n alld Bethma CuStOI11.111er(チWere6H(〉Stlmers and38即IeSt farnlerSin the1997Yala season. 111e numbcr of Hostfarmersi71CreaSedto18inthc1998Yalascason and thc number of GuesL hrmers decreased to25 farmers,llle reaSOn ねrthesc changcs was ulat there was alot of rain during thel†拍7/9ボMaha SeaSOnand Lhereforclherewas amplewaterinthe tankforthefol】owlngYalaseasoll.Asaresulr,the amounLofimgablelandirlCreaSed duringthe1998 Yala season as did the number of Host famlerS.1t WaS also LouTld that almost allthe Host farmers Yalaseasonthepu(TIPdtlmrr)ylnCreaSedtheareaof
Cultivation.¶1FLareaeultivated expanded h.omO.71
acr亡StOl.19acr〔・S.WitllregardtotllenumberoferopscuItivated,the PrObabilitythatafaE−mereultivatedin1997Yalawas 45%inthe case ofnon−pump OWnlTlgfamlニrS.Thc expectedvalue ofrlumberofcropwas O.69.1fthis farmerownedapumptheprobabilltV OfculLivation ln Yala wouldinerease to幻_6%and the expected valueofthenuml)erOfcropswoulda】soillCreaSetO l.15.Wc canalso confimt ttle rX)Sitiveimpact of PulTtPOW11erShiponCl)inthe1998Yalaseason.
In brlef,these丘ndings demonstraLe thalpump tcchnologyhashadahugeimpactont加progress
ufCl〕.1)Ⅵ7eassumedし11aLlhewビatherwasnonnalaIldo山げ conditionswereconsLanL.′meaverage values were
FarmLabor=2.6,AgeofHead=52.98,Education Dummy=0.92,AgrowellD11mmy=0.38.Cattlt)
Dummy=0.封in1997.In1998.2.6.52.32.0.92.
0,42,0.34.respecGvelv.
5.¶tFFUSIOIqOrNEWIRRIGATION TECHNOLOGlr AYDTIIECH.九NGEOFTRADITIONALⅥ仏TER
MANA(1ElIEmCIJSTOh・IThe Betlllllais a traditionalwater】T)anageme【lt
SyStemillSriI,anka.Tllissystemhasbee11praCtice(1 When there hasllOt been enough waterin the
holdinglankstocultlVateallofavillagePsfarmland.
Thiscustonltraditionallydivi(1estlleaVailablewaler
in Lht}[ank equal1y arnongthe farmers.Bethma
E)raCt]CellaS bf・en(】onein smallrscaleirrigatjon
SyStemS for 山ousand of yea門.However.this
Philosophy has also bceniLltrOduccd tolargcr
耕野托 一
82
cultivated thcir Bc血1nalar[d in both seasons However,18Guest血mersin血e1997Yala駅aSOm and10Guestfamersinthe1998Yhlaseasondldnot
c111dvatelamdallo(、ated to them under the Bethma 町如m.nble 6 shows that 20 Guest famer$
cul也vatediTlthe1997Yalaseason,yetthenumberof 払merswllOkepttoBe仇macustomwasonly4in 也e1997 and lin 山e1998 Yala seasひmS,
respec伽ely.In otherwords,16Larmers cultlVated di艶rentlandallocated tothem underthe Bethma 野面虹hd血七山Ⅰ℃■岬eret耶tyI把S Of血TnerS
(GroupAamdB).FameYSinGro11pAwereGuest EarmerswhodidnotcultlVateanyland(18血rmersin 1997and10faTmerSirl1998).FmersinGroupB were伽est farmers who didIIOt Cultivate hthe Be血ma 町S飴m,but cl此Ⅴ奴ed o也erland(16 iarmersin1997 and14 farmersin1998).The rclationshipbetweengivingupBethmacust(1mSarld ぬe possessiollOfimgation techl10lo即by these groups wasanalyzed.andtheresultsaregivenin
Tt血l06.118札仰boroIF●l・汀噌柑by8伽■■nd
Y一山euldv一個on
Tables7andと;.
We caJISee Clearly that Group A farmers have almostnoirrlgationtechnol咤yb11tGr軌1pBfarmers
do.AccodingtoGroupAfarmers,themainreason 血r not cultivatlng tlleir Bethmaland was 血e
distaTTCe tO the Bethmalands打omtheirllOmeS,
Sometimesitwouldbeasmuchas5knsfmma加Il house to山e Bethmalands,也ereぬre,仇e知†mer spenta】otoftimeintrarLSiLlnaddltion,therewere some difEICultleSiIIWateririSpeCtion. 111e Water Supplyi11thelargeirrigatlOnSChemeswas11nStable,
evem ror Be仇malamds ¢kamayake fぜ威F8り.
Furthermore,therewasapossibilibrbrcropfailure bccause almost allGro11pAfarmers did not own 仙eir 8Wninてgation technology_ W独 仏ese d膿eu止icsitis undcrstandable that the high
transacdon costs madeIおmers give 叩 Y出a cultⅣatlOn On Bethmaland.Famlt:rSin Group B COuldincrea$e the av由bbl8W如er by11Shg w血汀 pumps.Th海famergroupclaimsthe samel.eaS()n asGr(1upA(thedistancetoBethmaland血℃nlfheir hou5e)fornotcultivatingtheBethmahnd,butthey could eultivate their ownland,temユreland orthe lan(Ibeside the Rala Oya River.while Tleg7eeting BethmaぐuStOm,beca11Setheycouldstlpplywaterfor themselves.Ful廿1ermOre,GroupAhmlerSPOinted out that some Host farmers refused to share
thcirland with theln,In the field survey苓,We
Gu伽to NoCu伽 Tobl 1g97 Y▲l● Gu8tFon¶Or 28 18 田 Hくl鏡F如m即 8 0 8 Tobl ヱ6 18 叫 】998 Y■l● al写tFロnW 田 18 2ち H08tF■m●r †7 口 †8 Tobl 32 叩 埴
1佃=亨血d●d写OmO鳥¶●rSboG紺帥t卯∂血ね¶○帽G帥tt jt)lnln恥血相8nd80mOね「¶○帽didn■thvoBo仇∩Ⅶ
intom伯仏洲.
T8bl8丁・m8R即ゼ叩濾;pb鵬W00n()h8叩08如80仇m轟Cu血Mもdndth■P88∽貼iⅧ ofl鵬βゼont 血Ⅶぬ助(飢uD人血mo帽)
且卵胞如=膚vhrm●rd;dn teu帽v一也bo仇m●l帥d
Diぬn(〉Ob R血色Odby Wさ鴫「$ho血書8 ○仇椚
Be廿1m■】8nd Ho嘘fさけ鴨帽 inBo廿Im■
Tぬl1さg7Y8b 鈍P=1_A=り 〟P=0_Å::幻) 2(P=OA司)) 《P司A=8】 柑(P=1A=0)
柑98Y818 試P=1A=0) ヱ(P亡OA=萄) !■ l・l 叫P=司.A=0) 1(】(P三1A=り〉
りR糾■・OShp白油白08ⅣOnumb即・d牒附加rS血ohav¢Pump(P)8ndA郎W011(刃
T8bl08.ThoRo鵬○¶Ohわb●伽㈹nehlln騨8hBo廿w8Cl18tOm88れd廿lOP08き088lono†Im掛軸nto¢hnoloⅣ(川bDhm●帽)
R別18dnWhv向mordidn■tcuIUv書tOB仙mL ヽd
Tobl Diぬncot8
D曲mさIdhd
bnd向rm■r 7【P=5A=6) 双P尋A=き) 11(P=8A±9)
1997 = 仙・▼ 部P=8.A=1) 1(P=1Aヒ○) 4(P≡4A=1)
Ya18 1【P=可A=0) 1【棚)
Tot■l 11(瑚=7) 《囲A=8) 1(P亡1囲】 1¢(P=12A=10)
bnd向mor ⅨP=4A==3l ▲】
9(P=7.Å=8)
199さ b曲亭;d001バ∨Or 衣P=2Å=1) l(P=1.A=0) 3(P=aA=1)
Y■l■ 1(P=OA=8) 1(P==8A=0)
2【P魂A=0)
Tobl 鉱P三6A=ヰ】
《PミュA=3) l(P;1.A=0) l叫P=10メ芦丁)
りRgur舶in四川nth0888肝Oロリ汀Ibt〉rがfmo柑Whoh8Vt)Pl」ml)くP)8nd輌Il(A)
ExpallSiollOfCropDiversi丘亡atlOn
83cultivationaswellasthenumberofcropscultivated inpaddy鮎1ds.封owevertbese changes have also broughtaboutchangesinBethnacustoms,inthat 血一merS Who had access toimgatiqn technology couldincrease theirincomeif tl】eyi鮮10red the eLIStOmS,These 負ndings haveimportant policy implications 血r expanding CDin paddy丘elds.
Altho11gh pump ownershipincreased each farmerls profitirlOne particular season,On the wholeit efFectedwateravai1abilltyintheimgatlOn SCheme,
Whicheouldleadtoanunstablewatersupply.Asa result,farmers who do not own purnps have the incentive to obtain their own water pumps,Asa COnSequenee,it may decreasethe etfecdve water supply ofthe wholeirrigation system,Mizutanl ar訂1ed thatthe one ma】Orfactt)rWhichin且uenced theprogressofCDinSubackinIndonesiawasthe
assurance ofindividual tlSe Ofirtigation water
(Mizutani17】)_However,aeeOrdhlg tO Takeya,the norms behind Suback were very important to nlaintaLn COOperatlOrL and equalityin water availabilltyanddlStributlOn(TakeyaL川]).hthisstudy We Can COnCludethatthereis an urgcntIleed to formulate npw rules beyond Rethnla customs to
advanceCl).There are,however,many prOblemsirlthe developmentofCDwhicharedi代culttosl)1veinthe Shortrun.Themainproblemsarethemarketingand disbibutionofagricu]turalproducts,thehighcostof eu】tivati()n,pOOr eXtenSion services.andlack of availableplantingmaterials.nleSeprOblemshaYetO beaddressedimmediatelyinordertoexpandCDin
Paddy航e】ds.REFERENCES
[1】c.M.W的yarathna,C.RPanabokke,
】〕.B.Aluwihare.S,fl.Charles,and R.Sakthivadivel,
LLpotentlalforl)iversiAcd Croppingin the RICe LalldsofSriLmlka, lIIMICounlryPaper,SrlLanka No.14,1996,pp.1−105.
[2]Kikuehi,M..● AliaKaihatu・Tojoukoku−Kangai−
Bumon niokerllKangai・ky()kumen no Shuucn to con貢rmedthatalmostalloftheseHostfarmerShad
agrowellsandwaterpumps.Insum,ifGuestfarmers wererefused accessto sllaredlandsand hadwater
pumps and agrowe11s oftheir own.they could CullivateLheiro、VnlandsorillegallycultlVatebeside tlle KalaOyalむver.Ilowever,江these血rmers did rLOthavethe行ownirrigation technology,thenthey badtoglVeuPYalac111tivation.
Few studies have been conducted on Bethma CuStOmS_Asurveyconductedontwolargeirrigation SChemesin19$7PewahuwaandMahawelisystem H)concludedthattheseirrigatiollSChemeshadthe prmcipleofcqual1tybctwcenHostfarmersar[dGuest 血nllerS(Moragnda一】′〟19】,Ekanayakeど′〟【8り_
However,Our Study found that after the rapid di血1Sion of pumpirrigatlOn teChlOlogy and the progressofCD,Bethmacustomshadchanged.TT11S is because some farmers had their own agrowells and water pumps,SO Were at)le to bave a secure Water SupPly eveninthe dry season.¶1erefore,
fal・IrLerS Who owne(lwater pumps andirrigatiorl tech110logy tended tolleglect Bethma customs to eam moreincome.Today we can see howprlVate OWnerShip ofirrigation†echnology hasinfluenced the亡hangesin13ethmacustomsin]ar群imgation SChemes.Fina】1y,We Can argue that the equalibr pdncipleofwateravailabilibrinBethmacustomshas beeomeobsoleteduetoanincreaseinCDinpaddy
Aelds by using p11mpimigation【echnologyin Amunugamavi11age.However.thesechangesmight leadto someproblemsinirrigationschemesinthe
future such as unequalineome distrjbution,
depletion ofgrourldwaterlevels andincreaslng Of SalhiIyonfamla11ds.
1)AcultjvationrrLeeljngi汽WherefaTTnerSaEld鮎1d levelofEICialsmeettomakedecisionsrelatedto Cr opCultlYationinapartlCularseason.
,C(INCl.USION
In this study we pmved statistically that putny,
OW71erSlliI)hasincrcastTdlhenumberofacresofYala
耕野妬一
拡0喝O mO Tenkai−houkou−Sdl血1女a nol匂ngaト Tou油ino Doukon一日unsekihra −, Nougyou−
soug()u−kenky甘u,V81.45,No.4,1991,pp.1・74¢n J叩aneSe).
[3]ⅢhlC軋M., 劫iaKaihatul旬oukoku−K抑gai−
Shisutemu・TekiseトKanrinotameno Senryaku qSri lankaI10Keisu o CbtluShin to shite: No11gyOu−
SOugOu−kenkytlu.Vol.46,No,1,1993,pp,1−77(hl Japamesd.
[4]Kon叫H., SdI∬1bnoぬ【1g血attentohas並u きkisan −Dorai都n 血okenlMi別−dyouk弧OuSeio Ch11uStlinlカShite,、11997 Nendo Niho¶・nOu訂Ou−
keiz由gakkaiィonbu爪Shuu.1997,pp− 3弘369(h
Japanses).[5]Ma餌da,Y.,Midorjm)K扇札meino he・Mizu・Noumin.Nourintoukei−kyoukaj,1995,pp,
2も28(hJapanese).
[6]Masu血 Y.,Ⅹokusai−nOu訂Ou−billa血ron.
Nourinto11kei・kyoukal,19g6,pp.47−64(inJapanese).
[7]Mizutarli,S.,■■shigeIISeiyakukanoMizuriyou Shislltemu−hdoneshia「suba比uJnoKeikem− , Mizushigen no KDkatu toIiaib11n Cdited by
lmamぴa,N.弧dNagata,K.Noubuれ辱oul如6,pp.
121−218(imJapan亡父).
[8]REkanayakeandl),Groenfeldt∴ organizational A印eds ofImprovedl血gatlOn Manageme旺An E叩erimentinDewahuwaTank,Sri11nka: ⅠIMT WorkbgPaperNo.17,1990,pp.1−16・
[9]RMoragodaandD.Groenieldt,l organizational Aspects ofImprovedImgadon MBLnagement:
KaIanku出yaBlock,MallaWeliSystemH: sril.Ankn,
llMIWorkingPaperNo.19.1漸),pp.4欄.
[10]Takeya,HJ■shohyou:MizushigellnOKokatu b Haibum一触Iatu kara kanrie,■ Nougyou kei飽i−
kemkyuu,Vol.槌,No.1,1996,pp.56−58(h
Japanese).SUMMARY
hrecentyearsSrlI_ankan agriculturalpollCyhas 裏med at r由混血g cmp diversi鮎a血n since me c心血叫 has a仕aiれed selk山五dencyin rlCe producti0Il.Cropdiversif(CatlOninpaddy丘eldshas
arisen becauseofpumpirrigation developediIlt11e 1990s.Astudywascardedoutinavi11ageofthedry ZO11e durmg仙e1997and1998dⅣSeaSOn(Yala season)b explore the pやSSibi】i匝 Of crop diversifkatlOnin paddy丘elds and tofind(】utthe impactofpumpirrigationoncropdiversi丘cation.tt d鮒intended to examime仇e exis血gけaditioIlal WatermanagementCuStOmSCBethma)inthecontext Ofcropdivers通(・鵬on.Statis庇山analysISShows血t pumplrhEatlOnhashadasignificantlmpaCtOnCrOp divcrsiBcatlOninpaddyl組ds.1thasalsoiJtnueIICed traditiona】watermanagementctユStOmS()fthevillage.
Bethmaeustomsare gradua11ychangimgandpump owningfannersarebegiIlnmgtOneglecttradldonal water management cu如ms.′me resultlngIleaVy wi仇drawalof grotlndwater c8uld cause serlOlユS problemsthatmaythreatenagriculturalprcLducdvity in the futMe,Consequentlyit needs to be
emphasiヱedthatnewmlesandreg111a烏onsonw癒er management should be estab】弓shed by bo軌the govenmeTlt aTld farmers,and beimplemented as
SけOnaSp(ISSible.伽∫.勘助い釧兄柚m【抽抽..2Jr2α)¢い75一朗