Page 101 - 2022年第53卷第10期
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coordinatesystemofwater - energypartitioningwasestablishedtoquantifyeffectsofclimateandunderlyingsurface
                  variationonevapotranspirationseparately.Thentheoptimizedwater - energypartitioningframeworkwasappliedto
                  makeattributionofactualevapotranspirationin83typicalwatershedsin1900 - 2008.Itisdetectedthatvariationof
                  evapotranspirationinhumidbasinswithlowwaterholdingcapacityismainlydrivenbyunderlyingsurfacefactors
                  whileinhumidwatershedwithhighwaterholdingcapacity ,climatefactorscontributemoretoevapotranspiration.
                  Thetrajectoryofhydro - thermalstateinsemi - humid,aridandsemi - aridbasinswithlowwater - holdingcapacity
                  mainlymovesalongthearidityindexline,indicatingthatevapotranspirationismainlydrivenbyunderlyingsurface
                  factors.ComparingcalculationresultsbythismethodwiththosebasedonBudyko - Fudecompositionmethod,it
                  showsthattheattributionmethodbasedonthewater - energypartitioningframeworkhasagoodreliability.Inaddi
                  tion ,comparingtothetraditionalBudyko - Fudecompositionmethod,thespatialcoordinatediagramofwater - ener
                  gypartitioningisabletointuitivelyanalyzebothcontributionanddirectionofclimateandunderlyingsurfacechanges
                  toevapotranspirationinriverbasins ,aswellasthechangetrackofwater - energystateinthebasinunderdifferent
                  periods,whichmightmakeastrongpracticabilityinthefuture.
                  Keywords:spatialcoordinatesystem ofwater - energypartitioning;ecohydrologicalframework;Budyko - Fude
                  compositionmethod;attributionanalysis;globalbasins


                                                                                    (责任编辑:于福亮)


              (上接第 1228页)
                           Researchonthedynamicsoftheupliftandtransportcharacteristicsof
                                       sedimentintheLowerYellowRiverChannel

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                               CAIRongrong,ZHANGHongwu,ZHANGYu,ZHANGLuohao
                   (1.InternationalEconomic&TechnicalCooperationandExchangeCenter,MinistryofWaterResources,Beijing 100038,China;
                                   2.YellowRiverResearchCenter,TsinghuaUniversity,Beijing 100084,China;
                           3.StateKeyLaboratoryofHydroscienceandEngineering,TsinghuaUniversity,Beijing 100084,China)
                  Abstract:Inthispaper,thedynamicsoftheupliftandtransportcharacteristicsofsedimentintheriverchannel
                  oftheLowerYellowRiver (LYR)areinvestigatedonthebasisofpreviousstudiesusingalargeamountofhydro
                  logicaldata.AnupliftflowvelocityformulawithaclearconceptionandsuitablefortheLYRischosenbasedon
                  thegrainsizedistributiondata.Forthefinesediment ,thefourcandidateformulas(derivedbyShaYuqing,Dou
                  Guoren ,ZhangLuohao,andLuoShiqi)areallapplicabletotheYellowRiver.Forcoarsesediment,theformu
                  lasderivedrespectivelybyZhangLuohaoandLuoShiqiaremoresuitablethantheothertwo.Theupliftcharacter
                  isticsofsedimentintheLYRareinvestigatedbasedontheformuladerivedbyZhangLuohao,whichindicatesthat
                  coarsesedimentupliftalsooccursinthechannelofLYR underthemoderatefloodcondition.Then ,theHua
                  yuankoustation,theGaocunstation,andtheLijinstationintheLYRareselectedastherepresentativehydrolog
                  icalstations.Thediagramsoftheflowdischargeversustheratioofsedimentinsuspendedstatusareplottedre
                  spectivelybasedonthemeasureddatalowerthanthebankfulldischargeinthefloodseasonofthethreestations.
                  Theresultsshowthatthesedimenttransportcharacteristicsofthethreestationsaresimilarafterintroducingthe
                  conceptofupliftcriticalflowdischarge.Furthermore ,byanalyzingthesedimenttransportcharacteristicsofeach
                  station,therelationshipbetweenthesedimentparticlesizeandthefactorsrelatedtotheprobabilityofthesuspen
                  dedmovement,i.e.,theupliftcriticalflowdischarge,upliftprobabilitycoefficient,andthesedimenttransport
                  indexisgiven,basedonwhichtheequationbetweentheratioofsedimentinsuspendedstatusandtheflow - sedi
                  mentfactorsisfinallyestablished.Withtheproposedequation ,itshowsthatthecoarseparticlesinthecomposi
                  tionofsuspendedsedimentcanstillmaintainthesuspendedstatusaslongasthedailyaveragedischargeofthe
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                  LYRexceeds971m ?s(obtainedfromtherequireddischargetomatchthepredictedreductionofannualaverage
                  sedimenttransportinthenext30years ),whichindicatesthatincreasingthedischargeisaneffectiveapproachto
                  directlyenhancethesedimenttransportcapacityoftheLYR.
                  Keywords: TheLowerYellow River; sediment; upliftflow velocity; sedimenttransportdynamics; flow-
                  sedimentfactors

                                                                                    (责任编辑:李福田)

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