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

简介：Thehydrauliccharacteristicsattheconfluencereachofriverandlakeareinfluencedbymultiplefactorssuchasinflow,topographyandvegetationresistance,andareverycomplicated.Inthisarticle,theconfluencereachofYangtzeRiverandDong-tingLakeisselectedasaspecialexampleandahybridmodelisbuilttostudytheflowatthisconfluence,withtheconsiderationoftheinteractionsbetweenaquaticvegetationandflow.Validationtestsandcalculationsshowthatthemodeliseffectiveandhighlyaccurate.Thesimulationsshowthattheseparationleveeattheconfluencereachmaychangethedischargecapacityinthefloodplain,whichwouldbeenhancedintheupperreachofthelevee,hardlychangedinthemiddlereachandreducedatthelowerplace.Moreover,theseparationleveealsolimitsthewaterexchangebetweentheYangtzeRiverandDong-tingLake.

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简介：WiththecontrolofpointsourcepollutioninDianchiLakebasin,andtheexpansionofKunmingcity,non-pointsourcepollutionhasbecomethemainsourcepollutionofurbanwaterenvironmentandDianchiLake.Torevealthenitrogenpollutioncharacteristicsinwatershed,thisresearchselectedkeymonitoringpointsandsectionsatBaoxiangriverbasininrainyseasonwhichisthepeaktransportedtimeofnon-pointsourcepollution,thenitrogenandhydrologicalindicatorsaremonitoredsystematically.Thedifferentformsofnitrogenareanalyzed,thepollutionloadofnitrogenarecalculatedandstudiedatcardinalsections;combinedwiththeliteraturedata,wecomparedthewaternitrogencharacteristicsofDianchibasinandTaihubasin,themainresultsareasfollows:(1)Insummer,waternitrogenformofBaoxiangriverintheCaoheareaisdominatedbynitratenitrogen,whileinotherareasitisdominatedbyammonianitrogenwhichisaccountedfor31%-50%oftotalnitrogen;(2)ThewaterpollutionloadsofBaoxiangrivertendedtoincreasefromupstreamtodownstream,fromJunetoAugustthetotalnitrogenpollutionmainlycomesfromurbanareasandthepollutionloadis166.408t;(3)InDianchiLakewatershedandTaihuLakewatershednitrogenconcentrationofinflowriverishigherthanthatofthelake,nitratenitrogenconcentrationbetweeninflowriverandlakeshowsalittledifference,whileammonianitrogenconcentrationofinflowriverishigherthanthatofthelake.TheresultscanprovidethetheoreticalbasisfornonpointsourcepollutioncontrolandurbanwaterenvironmentplanningandimprovementinDianchiLakeBasin.

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：Thirteensedimentcoresamples(0-10cm)weretakenfromthesevenlakesinthemiddleandlowerreachesoftheYangtzeRivertodeterminethecontentsanddistributionsoforganicphosphorus(P)fractionsinthesedimentsoftheshallowlakesinthearea.TheorganicPfractionsinthesedimentswereintheorderofmoderatelylabileorganicP(MLOP)>moderatelyresistantorganicP(MROP)>highlyresistantorganicP(HROP)>labileorganicP(LOP),withaverageproportionalratiosof13.2:2.8:1.3:1.0.LOP,MLOP,andMROPweresignificantlyrelatedtothecontentsoftotalorganiccarbon(TOC),water-solubleP(WSP),algal-availableP(AAP),NaHCO3-extractableP(Olsen-P),totalP(TP),organicP(OP),andinorganicP(IP).However,HROPwassignificantlyrelatedtoOPandweaklycorrelatedwithTOC,WSP,AAP,Olsen-P,TPorIP.ThissuggestedthatorganicP,especiallyLOPandMLOPinsediments,deservedevengreaterattentionthanIPinregardstolakeeutrophication.IntermsoforganicP,sedimentsweremorehazardousthansoilsinlakeeutrophication.AlthoughOPconcentrationswerehigherinmoderatelypollutedsedimentthanthoseinheavilypollutedsediment,LOPandMLOPwerehigherintheheavilypollutedsediment,whichindicatedthatheavilypollutedsedimentwasmorehazardousthanmoderatelypollutedsedimentinlakeeutrophication.

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简介：训练策略的一条河的选择为更低的黄河(LYR)是极其重要的。当前，宽河的训练策略在训练LYR适用。然而，在在黄河盆的水文学过程的显著变化，以及从在黄河盆的社会经济的开发的立即的压力，使如果有可能性改变从到狭窄河的训练的宽河的训练训练策略的河，考虑必要。这研究调查通过数字模拟在LYR上训练策略的不同的河的影响。一一个维(1-D)模型被用来为未来模仿河的过程50年并且一三维(3-D)模型被使用学习典型洪水。学习集中了于河形态学，结果看那在两水分泌物的在场减少趋势和沉积负担是否坚持，在LYR的免职率将进一步减少不管什么策略被使用。特别，狭窄河的训练能达到目的与宽河的训练相比在LYR增加沉积运输能力。如果到来的水和沉积负担恢复到最后世纪的吝啬的水平，主要隧道收缩不管多么不可避免地由于沉积发生为宽河、狭窄河训练。最重要地，这研究证明狭窄河的训练在整个LYR上减少免职数量，但是它几乎不在减轻推迟的河的发展提供很少帮助。相反，狭窄河的训练能在河模式从高度漫步到蜿蜒地流变化的过渡活动范围引起沉积，进一步的变得更坏在那里的驼峰免职。因为关于在在可行工程的黄河盆，和缺乏的水文学过程的未来变化的无常，测量在LYR减轻推迟的河和驼峰免职问题，小心应该在为LYR训练策略的河里关于变化被行使。

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简介：【学习目标】Ⅰ知识目标:1.能理解运用以下词组短语:gothrough,goaround,goover,godown,goaroundabend,gopast,gounder并能简单介绍行进方向;2.能理解运用词组短语的过去式。Ⅱ能力目标:1.通过听力练习,口语练习,能够用英语说明行进方向,并能运用到实际中;2.能在过去式中简单运用词组短语来表达。Ⅲ情感目标:通过对新知识的学习,能够表达自己的想法,能够在实际中用英语说明行进方向;养成合作与共享的习惯。

简介：YamzhogYumcoLakeisoneofthethreesacredlakesinTibetansnowarea,locatedinNangarzeCountyofShannanPrefecture.NangarzeCountyisasemi-agriculturalandsemi-pastoraldistrict,andbecausethehusbandryprioritizestheagriculture,itwasnamed"Yamzhog(meadowlandinhighmountains)".TheYamzhog

简介：OnJuly20,2002,theStatePostalBureauissuedasetofthreestampspicturingtheQinghaiLakeshore,BirdIsland,andthedistantview.LocatedonthenortheasternQinghai-TibetPlateau,inWestChina’sQinghaiProvince,QinghaiLakeis3,196metersabovesealevel,andthebiggestinlandlakeinChina.Oilshavebeenusedtocaptureitsmagnificence.BirdIslandonQinghaiLakeisa

简介：Itiswell-knownthattheUnitedStates,ahighlydevelopedcountrywhetherinhigh-tech.orhighereducation,isinaleadingpositionintheworld.BasedonthecomparisonandanalysisofhighereducationbetweenChinaandtheU.S.,thisarticlehighlyaffirmstheadvantagesofAmericanhighereducation,offersanobjectivecommentonChina'shighereducationreforminrecentyears,andearnestlyindicatesthatChina'shighereducationneedstobeimprovedinordertofacilitategreaterdevelopment.

简介：Thereisalongrivernearmyhouse.Asmallboatisintheriver.Mysisterissittingintheboat.Sheiswearingayellowdress,thedressisnewandvery.nice.Amanisswimmingintheriver.That'smydad.Heisfreetoday,becausetodayisSunday.

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简介：WaterandsedimentqualitiesarestudiedbyanalyzingsamplestakingfromthemouthsoftheHaihe,Duliujian,NewZiyaandBeipairiversintheHaiheriverbasininnorthChinain2005and2001,inordertofindthechangesofwaterandsedimentpollutions.Theconcentrationsofheavymetals,arsenic,totalnitrogen(TN)andtotalphosphorus(TP)areanalyzedandresultshavebeencomparedforthetwotimes.Thein-situmeasurementforDissolvedOxygen(DO)andSedimentOxygenDemand(SOD)rateswerecarriedattheHaiheandDuliujianrivermouthsin2006.Theresultsshowthatthewatersofthe4rivermouthsarestillseriouslypolluted,thoughmuchimprovedinthecaseoftheHaiheandDuliujianrivers.ThemainpollutantsareTPandTNintheNewZiyaandBeipairiversandmercury(Hg)atall4rivermouths.Comparedwiththosein2001,theconcentrationsofalmostallmetalsandarsenicinthe4rivermouthshavedecreased.WaterqualityatHaiheandDuliujianshowsanimprovingtrend,whilethewaterqualityatBeipaiissimilartothatof2001.Incontrast,waterattheNewZiyarivermouthismoreseverelypolluted.Thesedimentsinthe4rivermouthsarenotseriouslypollutedbyheavymetalsbutarepollutedbynitrogenandphosphorus.Mostofthepollutantcontentsinthesedimentsshowlittlechangebetween2001and2005.Thein-situDOandSODmeasurementshowsthatthewatersattheHaiherivermouthisinthestateofoxygendepletion,andSODisimportantconsumerofDOattherivermouths.Theoverallanalysisshowsthatincreasingwaterpollutionandeutrophicationinwatersfarfromcitiesareongoingcausesofconcern.

简介：Palaeoflood水文学学习是全球变化学习的一个正面的题目。用标明日期方法的沉积科学，地形学和OSL，典型palaeoflood呆滞水存款在Qishuihe河山谷被学习。结果证明分别地，有21个palaeoflood事件的五泛滥事件在Holocene时期期间发生在43004250一B.P，42504190一B.P，41904100一B.P，41004000一B.P和31003010一B.P期间。palaeoflood山峰分泌物与水文学模型一起被计算。与计量洪水，历史的洪水和palaeoflood水文学数据的联合，洪水事件的档案在Qishuihe河山谷，和洪水频率山峰分泌物关系被扩大到超过10,000年曲线精确地被建立。在减轻的起的重要角色充满的这些研究结果冒险，水力的工程并且另外在半干旱的Weihe河盆的水资源的发展。

简介：TheJinshaRiver-LancangRiver-NujiangRiverareaisoneoftheimportantprospectareasfornoblemetalandnonferousmetaldepositsofChina.Ofagreatvarietyofgolddepositspresentinthisarea,thefollowingtypesseemtobeeconomicallymostvaluableandpromising:tectonicalterationtypeinophioliticmelange;polymetallicquartzveintyperelatedtointermediate-acidintrusions;finelydisseminatedtypeinfracturezones;mixedhydrothermaltypeintectonicfracturesofcarbonaterocks;hydrothermaltyperelatedtosubvolcanicrocks;volcanic-hotspringtype;submarinevolcanoexhalation-sedimentary-hydrothermalreformationtype.MetallogenicepochsareexclusivelyMesozoicandCenozoic,andoredepositsandorebodiesarecontrolledbylinearstructures.Magmaticactivityhasaffectedgoldmineralizationinvaryingdegrees,andgolddepositsarebasicallyofmesothermal-epithermaltypewithubiquitousandintensealterations.Ore-formingmaterialsandhydrothermalsolutionsshowmulti-sourcecharacter.

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