lSSN O912−7410

No．25 Februa†γ1995

け．ヾリJ「†てTJ†？

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一ForBetterLake Management￣
ThisNewsIetteTisalsoava‖ableinJapanese．

且打0月r7ⅥA爪ⅥVGCOび尺ぶgOⅣ

且mOⅣ郡上且βぴCA〃0Ⅳ、■∵

L一￣」一￣￣ protectionoflakeenviTOnmentS．
ThepurposeofILEC senvironmental
r−1
education proJeCt，Which now crosses
intemationalborders and covers six counけies（Japan，Denmark，Thai1and，Ghana，Braziland（′し・＝・「・●、Argentina），is topromoteenvironmental
educationatprlmaryandsecoTldaryschoollevels with emphasis on freshwater lake
environmentsin Asia，Africa and Latin
Amedca．
The fo110WlngrepOrtWaS Writtenby
OneOftheparticipants∴MichaelChiagbey of
Ghana，Onhisimpressionsofthecourse．
INTRODUCTION

塔
On血ewholeIfeelthetrainlngCOurSe
WaS Wellplannedandexecuted．Allactivitieswere
Aninternarionalenvironmentaleducationtralng
carriedoutontimeandthecotlrSeWaSaSuCCeSSfulone．
COurSefor7forelgnteaChersandhealthexpertSWa5held
bylLECinShigaPrefecture，Japan，OVeraperiodoflO ThedurationwasrathershortifyouconsideTthelively
daysbetween20−290ctober，1994．Thiswasthenrst discussionswhichhadtobestoppedbecauseoftime．
Althoughthereare魚nancialconsiderationsthathaveto
timethatILEChas held ashorttrainlng COurSe On
be takeninto account，the duration could have beenenvironmentaleducationandalltheparticlpantSagreed
thattheco11rSeWaSbothworthwhileandsuccessfu1．

Thecourseincludedbothlectures and study
visits，Theparticipants（from4differentcountries）

appearedtobefavourablylmpreSSedbythe Shiga
ProJeCt（ILEC sPilotPrqjectonLakeEnvironmental
EducationinShiga）．AlsoirlCludedonthecoursewere

SChooIvisits and on270ctober visits were made to
Morlyama−KitajllniorhighschoolandSawayama
elementaryschool．Thepurposeofthevisitwasto
inspecttheprogramandcurriculumwhichILEChas
beenhelpingtoimplementwiththegoalofpartitipation
OfbothelementaryandjuniorhighschooIstudentsinthe

extended to atleastthree weeks．However，ImustcongratulateILECfortheexcellehtorganizadonankindwaythattheorganizershandledtheparticIPantS．
CONTENTOFCOURSE

Thematerialswhichwere presentedwere
useful，howQVer，IfeelmorematerialscouldhaveglVenif

moretimewasallowedandmoreexpertswereinvoIved
inthelecturesanddiscussions．Forexampleanexperton
waterbornedisease，Whichisaseriousprobleminmy
PrqiectaIea，WOuldhavebeenextremelyuseful・Perhaps
handlingofseriousproblems舟omothercounbieswould

alsohavebeenextremelybene丘cial．

gotalotofideas丘omtheotherparticlpantS，Whichwi11

Enviror［mentalEducationinGhana．
CONCLUSION
The shorttrainingcourse was successftll・Howeveq，futurecouTSeS，ifthereareany，Shouldconsider
the problems of other countries，Environmental
Educationhasalongwaytogoandwemustallwork
relentlesslytodevelopmethodswhichareappropnatetoinformandeducatepeople，andthepublicgenerally，Onenvironmentalandgeographicalproblemsatlocations

help in developing better strategies to tackle

aroundtheworld．

USEFULNESSOFTRAININGTOMYCOUNTRY
IwasimpressedbyJapan sseriousattemptsto

COntrOlenvironmentpollution．TheworkonLakeBiwa
isverycommendable．1haveacquirednewknowledge
andideaswhichwi11beusefu1tomycounけy，Iwi11do

mybesttodisseminatetheideastothehighestlevelWithintheEnvironmentProtection CouncilofGhana．I

βJ7老Ⅹ「エA定吉β爪椛4制PO尺r且ⅩP且尺卿∫WO∫Jと仇〟Ⅳ0月那〃OクーWhatisgolngOnthelake？−
ForthescaleandthesocialimportanceofLake
Biwa，thenumberofresearChersstudyingLakeBiwais

AtthesymPOSiumforthepublic，SixresearChers
representlngtheparticIPantSOfBITEX−93respectively

limitedtoreachanyde丘niteconclusionorintegrated
idea・ItisthereforenecessarytohaveJOlntinvestigations
amongtheresearChers魚●Ommulti−disciplinaryfields，andpresentedtheresultsatfo1lowingfivesessions；1．Large
ScaleTranspor［，2．SmallScaleTransport，3．Importance
Of Perimeter，Surface and Benthic Layers，4．
BiogeochemicalChangesIndllCedbyTyphoons，5．

theresultsobtainedshouldbecomparedandbediscussed
mutudly．
BITEX−93（LakeBiwaTransportExpedment），

thefruitofsuchnecesslty，WaSOrganizedbyLakeBiwa
ResearchInstitute、（Japan）andtheCentreforWater
ReseaTCh（Australia）fromAugusttoSeptember1993．

Theaihofthisexperimentwastoexaminethemechanismsofhorizontalandverticaltransportofmass，
momentumandeneTgyinLakeBiwaandtorelatethesemechanismstothebiogeochemicalprocessoperatlngln
thelake．Thestudycoveredthetransporlbetweenthe
NorthandSouthbasins，Wherethehorizontalexchange
anddissoIvedandsuspendednll扇entsandplanktontake
Placemost丘equently．

The experimentinvoIved a totalof177

EnclosureExperimenl，andshowedthenewscenanos
WhichwouldsoIvetheproblems， WhatisgolngOninthelake ．Aftertherespectivesessions，PreSenterS，eight

Panelists fromvariousfields andaudiencesdiscussed
togetherinordertodeepenunderstanding．
Attheworkshop，Wehad40presentadonsbased
Onthedatacollectedduringthelastyearexperiment

Period，anddiscussedforthcomlngpaPerS，publicatio
andsmal1−SCalejointresearchestobeheldcontinuously．

Thesymposium／workshopmadetheinterdisciplinarystudiespossible；theword， compatible isuslngforcomputers，however，山iswordcanbealsouse
forthestlユdywhicht且kssamelanguage．

The most noteworthy results from the

SymPOSium／workshopcouldbeobtainedfrom enclosure
biologlStS，Physists，Chemists，teChnologlStS，Studentsand
experiment ．Thisexperimentaimedatsurveylngthe
Staffsfrom7countries．ThepalticIPantSCarriedotJtthe
COnditionof enclosed 1akewaterbyalarge−SCale
experimentuslngneWeStinstrumentSandhaveanalyzed

hexagonaLlubewithapolyestercurtain．Theresults
derivedfromtheexperimentdisprovedtlleuSualideathat
advocation wot11d greatly makeinfluence on the
LBRIandCWR，agalnincombination，held
BrTEXSymposium／WorkshopatOtsu／Nagahama，Shiga，distributionofphytoplankton；WeCOuldindicatethatthe

thousandsofsamplesandmorethanseveralgigabytesof
datafoTayeaT．

Japan，from5tolONovember，1994undertheauspICeS

app町entmultiplicationofphytoplankEoninLakeBiwa

OftheScienceandTechnologyAgencyofJapan，theJapanese SocietyofLimnoIogyandtheEcologlCal
SocietyofJapan．

was not only due to nutrient loading but watertemperaturestruCture（themocline）wouldbethekeyto

SOIvethemechamismofphytoplanktonbloom．

2〃かエAダムAmⅣ0月瓜打OP〃比β〃√A尺G且ⅣmALAPLATARIVERBASINREGIONALNETWORK
Theparticipantsconcludedthatlittleprogress
OneOfthelargestconcentrationsofreservoirsanywhere
h血be珊ma由ontke旗頭Ye血plement摘onof血e
intheworld・Fivecountries，Brazil，BoliYia，Urtzguay，
TheLaPlataRiverbasininSouthAmericahas

ParaguayandArgenlinasharetheriverbasin．Until

recommendationsofthe伽tworkshopwhilethegeneraldiagnosismadeathattimeremainedstiuvalid．
Theneedtoenhancesystemiccommunication，
informationandexperiencesbetweenthesenations，To
COOperation，interchange
ofinformation and thepromoteinteraction，thelstLaPlataWorks］10P（lnternationalWorkshoponRegionalApproachtothe OptlmizatlOnOfresearch，Planning，Operationand
managementofrive〟reseⅣOirswasstressed．
ReservoirDevelopmentandmanagementinLaPlata
Itbecameveryclearfromthediscussionsthat
RiverBasin）wasorganizx，dbyILECandUNCRD（thetheestablishment，implementationsandoperationsofa
UnitedNationsCentreforRegionalDevelopment）in
BrazilandArgentinainAngust1991．Ttturnedouttobe regionalnetworkintheLaPlataBashwasanurgent
needtodevelopfurthertheinteractlOnandalreadyagreatsuccesswithmorelhan80particlpantS・existingcooperation，andtopromotefutureactlvities，
Toexpandanddeveloptheworkdonebythe
Prqjectsandprogrammesrelatedtowatershedandwater
nrstworkshop，aSeCOndLaPlataWorkshopwasheldinresourcesmanagement・Plannlng，reSerVOirprotection
ArgentinainAugust1994・ItwasheldbytheSalto
釘山rehabili也tiom
GrandeReservoirandinBuenosAires・TheWorkshop
O輌Y朗㌦theNetwork
hadmorethan50distinguishedparticlpanlSincluding
recentyearstherewasaminimumofexchangeof

reservoirmanagersfromthefivebasincountries，

1ake／reservoirenvironmentspecialists，urbanplanning
SPeCialistsandhighrankingstaffofinternational
developmentagencies・IngAlbertoCalcagnoservedasa
localorg抑izer．

Atthefirstpartoftheworkshopin Salto
Grande，manyPreSentationsweremadeonreservoir
Waterqualitymanagementandfisheries．Lect11reSand

actualexperiencesonmode11inBWerealsoprovidedby
ProfessorSven・E・J＠rgensen・Dmingthelatterhalfof
theoftheworkshopatthemeetingroom ofthe
In［eramerical−DevelopmentBank（IDB），institutlOnal

aspects飲）rlake／reservoirsenYironmentmanagementof
thebasinwasfocussedon．
The finalrecommendationsincluded an

TheLaPlataBa扇nnetworkshouldimprove，
Stimulateandenhance血fo1lowingac血idesamongits

Participants：⊥、「血り吐血」！・いr・lさと血lし‖l、山し‖川l山

一In時評ati㈹Of血c血0血advほ蔦＝めd血柁lopぬmal
trainingcourses（postgraduate），in−SerVicetraining，

env血mbleducadom−Exchangeofinformationthroughpublicationof
newsletters，SynthesISandjointpapersasaresultof
COO画ⅦWOrkGener山門blicin払rmadon．
−Imdustryofregionalcapacities：Organizations，reSearCh，
andtechm）logydevelopmentprqjects，humanreSOurCeS，teachingandけainmgactivities，teChnologyavai1abilities（models），databanks，etC，
21Co（）mdon

establishrnentofaregionalorganizationconsistlngOfM叩mtOf餌血併COOper鵬onamong仇ev訂わ朋
institutionsinthewatershedasawaytostimulate
institutes／organizationsinthebasin・Followingthe
technologlCaltra・1SferjointresearchprqJeCtS，WOrkshops
recommendationtheLaPlataRiverBasinRegional
andseminars，bothonspeCifictopicsorintegrated
Networkwasestablishedon19August1994・Ing．A．
CalcagnotooktheofficeascoordinatoroftheNelwork．

approachestowatershed〟eservoirsandwaterresources

Severalorganizingcommilteememberswerealso

m肌鳩emenL

appointed．

31h血氾radon

DevelopmentofintegratedactlVitiesirlthenetworkand
amongthevariousregiOns・Thenetworkwouldprovidea
conceptualumbre11a ，abasic structure withan
approachtos血一ulateintegratedmanagementactivities．

TtisbecomlngmOreandmoreevidentthattosoIvethe
COmPlexproblemsofwaterresourcesandreservoir
managementitis necessary to develop a true
interdisclplinaryapproach with asystematicand

activitiesamongltSmembersandalsotoproposefurther
prqects，PrOgrammeSandtrainlngCOurSeS，Oneofthe

mostimportantobjectivesofthenetworkistoenhance

artict）latedoverview ofbiogeophysical，SOCialandeconomicproblems．Thenetworkwi11havethetaskto
improveandspreadthisconceptualframeworkinthe
basinin orderthatadequatemanagementofwater
resourcescanbeachievedasares111tofthisapproach．
4）Coordination

qualitycontroloftheprqjects；tOlユnifyandstandardize
methodologleS，enVironmentalqualityindicators，fleld

datacollectionandprocesslngPrOCedures，geOgraphicalinformationsystemsdevelopmentandremotesenslng
dataacqulSition techniques；tOprOVide basis forintercalibradon，prOmOteeXPOSteVal11ationofprq）eCtS

andstimulateinterchangeOftechnologleS．

The network willhave the fllnCtion to coordinate

PJ・（一／fJ両J川／・．l・（ り〃．r（リ・ぐ〃（・（・J〃J／け／）川ナノ‖（りり＝JJ′川（J／（−、・里′−（リ・ぐ〃（・（＝り＝／け（∴Ⅷ．ヾlリ●l・（JJ／り〃 川（／〃（川叶ヾぐ〃けJけり†
エαたe∫

byProfessorSabt）rOMatsuiofKyoto
UniversityWhochairedtheprogramme
COmmittee，With the aid of slides，ProfessorMatsulgaVe aneaSy−tO−
understandlecture on theconferences，
fromtheInauguralMeetingatLake
Biwa，ShigaPrefecture，tOthe5th
Conference，Which was heldlastyear
Onthe shores ofLake Maggiorein
ltaly．FtofbssorMatsuithenwentonto
introduce the6th Conference，Whichwill be held on the shores of Lake
KasumlgauraneXtyear．
A Preliminary Conference was held on 21
After ProfessorMatsui s talk，Dr．Riccardo deAugust1994attheTsuchiuraCitizen sHallforthe6th
Bernardi，ChairperSOnOfthe5thInternationalConference
International Conference on the Conservation andOntheConservationandManagementofLakes（andManagementofLakes，Whichwi11takeplaceinOctober
DirectoroftheIstitutoltalianOdiIdribiologia），SpOkeon
1995inKasumlgaura．Thethemeoftheconfbrencewi11
EnvironmentalProblemsinItalian Lakes andlakes
be HarmonizingHumamL娩withLakes． Aboutl，500 MaggioreandOrtaasSuccessfulExamplesofCorrect
PeOplefrom39prefecturesattendedthepreliminary
ManagementLeadingtoRestoration． HeasseTtedthat
COn免rence．
theactivitiesofcitizensplayedaslgnificantrolein
Theconference openedatlO a．m．fo1lowlng Purifyingthe water oflakes Magg10re andOrta，
SpeeChesbytheGovemorofIbarakiReLecture，Masaru
SuPPOrtlngthiswithexamples．Inthe1970s，througha
Hashimoto（alsoPresidentofthe6thInternational
PrOgrammeinstitutedunderltaly senvironmental1aws，ConferenceontheConservationandManagementof
LakeMaBgiorerecoveredfromeutrophication，While
Lakes），theDirectorGeneraloftheEnvironmentAgency，
LakeOrtabouncedback丘omharmfu1contaminationand
SoheiMiyashita（See Photo），the Minister ofacidification，Construction，Koken Nosaka，and the Mayor of
Theafternoonsawprese11tationsonthreekey
TsuchiuraCity，HiroyukiSukegawa．A summaryonthe issues：lakesaTldorganisms，lakesandlifestyle，andlakes
progressandpurposeoftheinternationalconferencesonand culture．Allwere based on the common theme of
the conservation and management oflakes was glVen
lakesandhumanlife．Fromamongthe41proposals
4

Of丘cial1yreceived，15presentationswereglVen，負veon

eachissue．TheaudiencealsohadtheopportunltytOaSk
questionsando脆rtheirownoplnions・A允erthepresentations，aPaneldlSCuSSiontook
Placeonthesu切ectofestd）1ishingawayoflivingthat
wouldbegendetoLakeKasumlgaura・Coordinatingthis

discussionwasprofessorHiroyoshiShiigalOfthe
University Tsukuba，Who chaired the Executive

presidentofKasumi，Ms．KazukoTomiyama，aSOCial
critic，andMr．TakehikoFuk血shima，areSearCheratthe

NationalInstituteforEnvironmentStudies，heldalively
discussion，Whichincludedtheirimpressionsofthepresentations．
Inaddition，theCitizens CollnCilfbrtheWorld
LakeConferenceheldtheKasumigauraCitizens Nightandthe WaterandEnvironmentFairandFleaMarket．
TheresidentsoftheKasumlgaurabasinhavegreatCommitteefortheprelimlnaryCOnfbrence・Thepanelists，
Mr．NorihikoIkeda，formeTChairoftheYouthChamber interestinthelakeandareexpectedtobecomeevenofCommerceofTs11Chiura，Mr．AkioKanbayashi，

moreacdvein血1Sareain山enextyeaL

ワ4比丘CACm∫
Janw15−30
FacthdingmissiontothePhillipinesandAustralia
JanuarY24−March30
4thILEC／JICA LakeWater Quality Management
TraimgCour㌍h5higa
Febw14−17
Brazilian血s丘omICETTⅥ鳩komd
Febw23−Marchll

Indm廿血eeswdmed
M訂ChWorldLakeEnvironments−Vol．1AsiaandOceania
publlS旭ApTiHA−SymposiumforEuropeanWomen，sstudyTour
entitled OntheShoresofLakeBiwa−AGatheringof
Women heldinShiga，OrganlZedbyILEC，Shiga
牡e如e肌dJ甲mFoundadon
GDril g0fncialOpe血gCeremonyoftheUNEP伽ternational
EnY血mtTech柑logyCen甘ehOsaka
A血114−15
Cooperationintrainingcourseforanexpertofthey仕由niMtemno止vnE ale皿V

ADrill9
TLECLectureMeetingonWaterEnvironmentinShiga
May川
CooperationinRitsumeikanUnlVeTSitysymPOSiumin
Shlga
Mav18−21
Cboperationin Wa蛤rJapan 94‖inOsaka
June 28
ReseuchExperimentonEnvironmentalEducationin
Shiga

Julv2」3
FactfindingmissiontoIndonesiaonlakerelated
intemationalcooperationprqjects
J山Y3−柑MissiontoVenezueraforJICATrainingCour㌍OnLake
Valencia
Julv 14
CooperationinthetrainhgcourseofChina−Japan
RiendshlpCentreforEnvironmentalProtection
July14一叩
Cooperationinu6thIntemadonalSymposiumonSaline
L血sinChina‖
Au！叫St2
山Y止seFr蛤aWwiBe止L hm画oC

Aum凱6−27
M柑由mbSo油AmedcaonEnvimt由良血cation
Au空u飢7−20
MissiontoLaPlataWorkshopinArgentina
Au亡u凱7−20
MissiontoSwedenfortheWMOWorkshop
Au寧uSt21

Cooperationin＝prelimlnaryConferenceofthe6th
WorldLakeConferenceinIbaraki r
Au印St24
Conclusion ofMemorandum with UNEPInternational
EnviroTmtTechnologyCentre
Au寧那tmGuidelineBookVol．2−Spanishversion−m PublishedSe咄mber3
Cooperadonto theRohdoh−Kinkoseminar hShigaSe咄mberll
CooperationinrLaturemuSicftstivalinShiga
September25−Ocmbr12
Fact findingmission to Europefor World Lake5

Con短renceBoouet
OctoberlO
Cooperationin‖KusatsuCitizens Festival
October13−ほCooperatlOnin‖GLENTEX 94‖inYokohama
October17−22
Mission to Thailand for the Expert Meeting on
UNEP／GEMSPrqject
October17−November5
Factfinding missiontoIndonesiaonlakerelated
intemationalcooperationprqects

October20−29
Trainlng Course onenvironmentaleducationheldin
Shiga

Oct峨
WorklLakeSeminarforCid2mS

heldinShiga

Octob訂＝Guidelirk，BookVol・2，FrenchVersion−1rptJblrshed
Novemb訂

LSurveyofStateofWorldLakesVol．5 published
Dec引山鹿rll−21
Fact finding mission to China for World LakeCon飴renceBookkt

エA麒g∫OFr甜gⅥ／0月エβ≡rrL▲．．■■仁Fトート﹁−トFしr⊥L丹r
︹﹁

ー
ト⊥
⊥∴′
／／

L・AKEKASUMIGAURA（JAPAN）
MorihiroAiヱaki（Waterand SoilEnvironmentalDivision，the
NationalInstituteforEnvironmentalStudies）
LakeKasumlgatJra，thesecondlargestlakein
Japan・islocatednearthemouthoftheTonegawaRiver，50kmnorth−eaStOfTokyo・Thislakewasorlglnally
brackish・TheHitachigawaRivergatewasbuiltin1963，

500mupstreamOftheconfhenceoftheHitachlgaWaand
TonegawaRivers・Beforetheconstructionofthegate，

thelakewasprlmarilyusedforfisheriesandwater
qualitywas maintainedatreasonablelevelforarl

LakeKasumlgauraCOnSistsoftwomainbasins
Cal1edNishiuraandKitaura．Nishiuraisusual1ycalled
LakeKasumlgaura，andhastheね110Wingdimensions；Surfacearea178km2，maXimumdepth7m，meandepth4m，VOlume8xlO8m3，WaterShed1950km2．LakeKitaura（Kitaurabasin）isconnectedbyachannelwithLake

Kasumlgallraandhasthefollowlngdimensions；Surface
area39km2，maXimumdepthlOm，meandepth5m，VOlumel．9xlOBm3，WaterShed437km2．

ThepastlOOyearsofthislakemaybedivided
intothreeperiods．Inthe負rstperiod（−1945），負sherywas

PrOSperOuS．Continuous annualcatchof8000tonsof
eutrophiclake．However，aftertheconstructionofthefisheswererecordedinthisperiod．Pondsmeltand
Japanesewhitebaitwerethemainspeciescaught．
gate，thelakechanged打ombracklShto魚■eShwaterafter
Transporはtionbywaterwasalsoactiveinthisperiod．
theimplementationofawaterresourcesdevelopment
FamoustownSarOundthelakeweredevelopedbywaterplan・Theareassurroundingthelakehavebeenrapidlytransportation．Reclamationworkswerealsostartedin
ChanglngSincedleCOnStruCtionofthegate．
6

thi叩dodInthesecondperiod（1945−1963），鮎heryand
reclamationworkswereactivejustasinthe丘rstperiod．
However，Watertr争nSpOrtationdeclinedandalmost

disappeared，andlandtransportalionsystems weredeveloped・Water quality changedto abrackish
COnditioninthisperiodduetothe■dredgingworkof
Outflowriversfbrfl00dcontrol．Asaresult，agnCt［ltllral

damageresulting from thellSeOfsaltywater for
imgationoccurredinmanyplace・TheHitachigawa

WatergateWaS COnStruCtedbothtocontrolfl00ds andpreventdamageOfagnculturallandsfromintruSionof
brackishwaterstartedinthisperiod．Thefirstwater

highofabout8，800tonsin1983anddecreasedtoabout
6．000tonsin1991．

Land use in the watershed of Lake
Kasumlgaurain1987wasasfollows；tOWnarea，10．7％；
paddy丘elds，21．6％；fieldsandorchards，16．9％；forest
etc．，40．5％；lakesurface，10．3％in1987．

Recentwaterqualityinthislakeisshowninthe
Table．AlthoughhumanaCtivitieshaveincreasedinthe
WaterShedinrecentyears，Waterquality hasbeen
maiIltainedataconstantlevel．Throughanumberof
COuntermeaSureSOVeraPeriodofmanyyearsIbaraki
Prefecturehasmadeeffortstorecoverthewaterqt［ality．

SuPPlyfordomesticusewas constrt］Ctedin1960．

Thefactthatsmallchangesinwaterqualityhave
OCCurredbrthebetterin thelastdecadeisevidenceof

Subsequently，KasumlgauraWaterSupplyworkinthe

thesuccessofthesecountermeasures．However，highS

about620，000people11Sethelakewaterfordrinkingand
Otherpurposes．
Inthethirqperiod（1963−），thefundamental

COnCePtOflakewaterutilization was chanBed．A
COmPrehensivedevelopmentproJeCtforthelakewas
Startedin1971forthepurposesofdevelopmentofwater

Secchidisktransparencylevelshavebeenobservedin
winterinrecentyearswiththedecreaseofchlorophyllra
COnCentration・Dominantphytoplanktonspeciesinthe

SummerPeriodhavealsochangedinrecentyearsfrom
Microcystisspp・tOfilamentousbluegreenalgae．Thesephenomenashowthatseverechangesintheecosystem
haveoccurredinthislake．

resourcesandfloodcontrol．LakeKasumlgauraWaS，
hereon，eXpeCtedtoserveasareservoir．Reclamation
works伽ishedin1973，Totalreclaimedareainthelake
reached2，660hectorswhichisequlValentto12％ofthe TABLEWATERQUALITYOF p

PreSentlakesurface．Alargeareaoflittoralzonewith
abundantaquaticplantsdisappearedduetothiswork．
Annualcatchof負sherylnCreaSedfrom1965duetothe

LAKEKASUMIGAURA
T−P T−N Chl−a S D COD Cl￣（〃釘1）（mg／1）（〃釘1）（m）（mg几）（m釘1）

niSep rutlcpafO止tsehdnatobr mfoesu

1990 64 0．96 56 0．5 7．6
thelake．Anal1timehighannualcatchof18，000tons
WaSreCOrdedin1978・Recentlythefisheryindustryhas 1991 71 1．3
58 0．6 6．8
facedmanyproblems，andthenumberof且shermenhave
1992 77 0．94 77 0．5 7．4
decreased．

In山e12years餌Im1978−1990

thepopulationinthewatershedincreased
byabout200，000peOpleandthemmberof
reglSteredfactoriesincreasedbyabot）t
2，000，with a300％incresaseinindustrial
PrOduction・Apublicseweragetreatment

Plantopenedin1979，withservicesbeing
providedtosome200，000peoplein1988．

Pigfamlinghasbeenacliveinthisarea，and
abotlt400，000headsofpigswererearedin
1991・Carpcultureinpenswasstartedin
i963andincreasedraI）idlyinthelake．

AnnualcatchofpenculturedcarPreaCheda

51
42
45

F＝・沌（・り〃両川斤l、（リJh
Kasumlgaura 95

CorrespondenceAddress：
Secretariat ofthe6thInternationalConfeTenCe On the

6thIntemationalConference on the ConserYation and

COnSeIYadonandmanagementoflakes

ManagementofLakes−HarmonizingHumanLifewith
Lakes−Towards the Sustainable Use ofLakes andl−5−38Sannomaru，Mito，Ibaraki310Japan
Phone：＋81−292−24−6905

Reservoi柑−

触： ＋81−292−33−2351

Dale：23−270ctober1995
Venue：TsukubaandTsuchiura，Ibaraki，Japan
Orga血沈rS：払∬abP陀飴ctⅣe狛dmEC
O踊cialLanguage：JapaneseandEnglish
Sessions：
1，UtilizationofLakesandReservoirs，andConservation
OfLakeEnvironments
2．PreservationandManagementofFreshwater
Resources
3．Mechanism，ControlandPrediclionofEutrophication

Forum for Inland Lakes
ForumOnCaspian，AJalandDeadSea
Date：27−29March1995
Venue：UnitedNationsUniversity（Tokyo，Japan）
on27March
LakeBiwaResearchInslitute（Shiga，Japan）
On28＆29M訂ChOrganizers：TheUnitedNationsUniversity，UNEP−
IntemationalEnviTOnmentalTechnology
Center，KyotoUniversity，LakeBiwa
ResearchInstitukandmEC

4．SourcesofChemicalPollutantsandTheirFatewithin
Lakes

A FoTumOnCaspian，AralandDeadSea wi11

5，AdministradveAspeCtSOfLakeEnvironment
Conservation
6．RoleofCitizeTISandEnte7PrlSeS，andEnvironmental
Education
7．intem釦ionalCoo匹radon
8．Kasumlga11raSession

beheldinvoIvingresearchersandassistamceorganizations
thathavestudiedenvironmentalproblemsregardingtheseinlandlakes．Theforumwi11includepresentationof
Studiesanddiscussionsonrelevantthemes．Althoughthe
entireForumisopentothegeneralpublic，theyare
espeCial1ylnvitedtoparticlpateinthesessionsheldon28
March

ハノ、上Jハl／／り＼、1JJIJ、J・J・、＼l、〃い＼、l什＼Jl・′l川／／、／ソイ、J・川＼ハIJT＝＼3−1325Kusa仁Su，Kusalsu−City，Shi卵525．Japa爪Te】：＋8l−775672155．Fax：＋81−775−67−2156

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