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简介：ThehydrodynamicandthesedimenttransportpatternswithintheestuaryoftheYangtzeRiverarecomplexbecauseofinteractionoffluvialandthetidalforces,dependingonfreshwaterdischargeandtidalrange.Basedonthedatameasuredinrecentyears,thispaperdiscussesthecharacteristicsofflowandsedimentmovementintheYangtzeRiverEstuaryandtheirinfluencesontheevolutionoftheestuary.

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简介：ThisarticleaddressessedimentresearchcarriedoutfortheThreeGorgesProjectsince1993,whentheconstructionoftheprojectwasformallystarted.Emphasisoftheresearchhasbeenplacedonthesolutionofrelevantproblemsarisingfromdesignandconstructionofvariousstructures,includingsedimentationproblemsintheChongqingreach;layoutoftheupperlockapproachchannelandwaysandmeanstomitigateitsdeposition;increasingreservoircapacitybyoptimizingreservoiroperation;compensatingdepthofflowrequiredbynavigationbelowtheGezhoubaProjectcausedbyscouring;mitigationofadverseeffectsoferosiononthereachfromZhichengtoJiangkou;andevaluatingscouroftheJinjiangreachcausedbyreleasingflowsoflowconcentrationsfromtheTGP.Inaddition,reductionofthesedimentloadenteringintothereservoirareaoftheTGPintherecentyearsaswellasthatexpectedoftheprojectedconstructionoflargehydropowerstationsontheJinshaRiverupstreamoftheTGPreservoirisalsonotedanddiscussed.

简介：推迟的沉积在河和存款里从流动的水吸附污染物质到床上。然而，在河床沉积积累的污染物质可以为时间的一个长时期通过食物链影响简历社区。学习这个问题重金属的集中(Cr，Cd，Hg，Cu，Fe，Zn，Pb并且作为)在2006-2007期间在长江的中间、更低的活动范围在水，沉积，和鱼/无脊椎动物里被调查。重金属的集中比在水里在沉积更高是100-10,000时间。Benthic无脊椎动物由于他们的最近在他们的纸巾有重金属的相对高的集中到污染沉积。而phytoplanktivore鱼例如银鲤鱼，积累了重金属的最低集中，Benthicinvertivore鱼有重金属的中等高的集中。Cu，Zn，和Fe的集中比Hg高，Pb，Cd，Cr，并且作为在织物样品。重金属的集中比在湖沉积在河沉积是更低的。相反地，重金属的集中比在湖水里在河水里是更高的。当进水身体的一个污染事件经常是临时的时，污染物质的效果可能由于他们全神贯注于沉积的趋势是长寿的然后释放进食物链。重金属在下列顺序被集中：底部材料>居于水底的鱼和benthic动物志>中间降低的层鱼>上面中间的层鱼>流水。

简介：Basedonhydrographsof"81.7"floodandtopographiesof1980and1993,a1-DmathematicalmodeloffloodisdevelopedtostudytheeffectsoftheGezhoubaProjectonfloodpropagationalongtheYichang-JianliriverreachesintheYangtzeRiver.Calculationsandanalysisshowthat,after13years'operationoftheGezhoubaProject,thefloodpeakstageshavebeenlowered,thefloodcurvesofstage-dischargerelationshiphavebeenmoved,however,theeffectsontheflooddischargesandstoragescanbeneglectedrelatively.

简介：TheThreeGorgesProject(TGP)isaworldknownprojecttoutilizeandmanagethewaterresourcesoftheYangtzeRiver.Thereservoirstoreswaterattheendofthefloodseason,andreplenishesdownstreamreacheswithwaterindryseasons.Inadditiontosuchbenefits,theTGPhasirreversiblychangedthehydrologicalprocessandtheriver-lakerelationofthemiddleandlowerreaches.Inthispaper,ahydrodynamicmodelwasestablishedtoquantifytheimpactoftheTGP'soperationonthewaterexchangebetweenDongtingLakeandtheYangtzeRiverduring2009–2013.Theresultsindicatedthat:theoperationoftheTGPhasconsiderablyreducedthepeakdischargeandthefloodvolumeofthemainstreamandtheDongtingLakearea.TheinflowvolumefromtheYangtzeRivertoDongtingLakeviathreeoutletsdecreasedby1.9–3.5billionm3/yr,whiletheoutflowvolumefromDongtingLaketotheYangtzeRiveratChenglingjiincreasedby0.3–1.6billionm3inSeptemberand0.4–0.6billionm3inOctober,respectively.Thisresearchprovidesvaluableinformationforfloodcontrol,irrigation,andwaterallocationinthemiddleandlowerreachesoftheYangtzeRiver,andservesasatypicalcaseforinvestigatingtheimpactofotherhydropowerprojectsaroundtheworld.&2017InternationalResearchandTrainingCentreonErosionandSedimentation/theWorldAssociationforSedimentationandErosionResearch.PublishedbyElsevierB.V.Allrightsreserved.

简介：Preferentialflowistheordinaryphenomenonofrapidandnon-equilibriumtransportofwaterandsolutesoccurringinmostsoil.Itcauseslatentpollutionofgroundandsurfacewatersandaffectsrunoffyieldandflowconcentration.ThispaperstudiespreferentialflowforadarkconiferousecosystemintheupperreachareaoftheYangtzeRiver,establishesaclassificationforthepreferentialflowanddiscussestypesofpreferentialflowwithasoilcolumnexperimentusingahomemadeapparatusanddye-traceranalysis.Thepreferentialflowismainlyunsaturatedgravitationalflowintheupperlayeroftheslopedepositformatureforestsoil,whichisdominatedbyawetnessfront,andtheflowgraduallytransformstomacroporousflowasthesoillayerdeepens.Theobservedpreferentialflowintheyoung,middle-agedandover-matureforeststhathavegrownonglaciallateralmorainesismacroporousflow.ThepurposeofthisresearchistoanalyzesystemicallythebehaviorofsoilwatermovementforadarkconiferousforestecosystemintheupperreachareaoftheYangtzeRiverandtoprovideatheoreticalbasisforeffectivewatershedmanagement.

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简介：AfteroperationoftheThreeGorgesProject(TGP),thereisanewevolutiontendencyforriversandlakesinthemiddlereachesoftheYangtzeRiver(i.e.theChingRiverreaches).Inrecentyears,theweakeningconnectionrelationshipbetweentheYangtzeRiverandDongtingLakehasresultedinaseriesofproblemsforfloodregulation,waterresourcesutilization,andaquaticecosystemprotectionintheriver-lakejointarea.Inthispaper,thehydrologicalcharacteristicsandfluvialprocesseswithintheriver-lakejointareaarestudied,andpossiblemanagementstrategiestomaintaintheconnectedriver-lakerelationshipareproposed.Toachievethisobjective,theevolutiontendency,suchasthezero-flowproblemandriverregimeforthreemajoroutlets(i.e.theSongziOutlet,TaipingOutlet,andOuchiOutlet)toDongtingLakefromtheYangtzeRiver,isanalyzed.ItisbelievedthattheSongziOutlethasacomparativeadvantageinflowdiversionovertheothertwooutlets.TheRangeofVariabilityApproachisintroducedtoidentifyhydrologicalcharacteristicsattheSongziOutlet.Severalcharacteristicvaluesofflowdiversionfromthisoutletduringdroughtperiodsaredetermined.Then,thefluvialprocessesintheriver-lakejointareaarestudiedbycomparingtopographicmapsandusingcontrolgaugestationdataofvariousyears.ThewaterandsedimentfluxareanalyzedbeforeandafteroperationoftheTGP.Finally,basedontheresultsobtained,twopossiblemanagementstrategiesarerecommendedandcorrespondingparametersareestimatedtostrengthenandmaintaintheconnectedriver-lakerelationship.ThisanalysistakesintoaccountoperationoftheTGP,mainstreamshiftandincreasingriverbedscourintheChingRiverchannel.Torestoretheflowdiversionconditiontothatinthe1950sor1960s(i.e.140m3/sofflowdiversioncorrespondingto5500m3/sofflowattheZhichengstation),itisestimatedthattheriverchannelaroundtheSongziOutletshouldbedredged1.4munderthecurrentriverbedsituatio