简介：TheYangtzeRiveristhelargestriverinChina,about6,300kilometreslongwithadrainageareaandpopulationaccountingfor18.8percentand33percentrespectivelyinChina.AimingatincreasingforestandvegetationareasonthemiddleandupperreachesoftheYangtzeRivertocontrolwaterandsoilerosion,theChinesegovernmentin1989decidedtocommenceaconstructionprojectfortheprotectionoftheforestsystemonthemiddleandupperreachesoftheYangtzeRiver.Theprojectcovers645counties(citiesanddistricts)in13provinces,

简介：<正>WiththerecentannouncementofthewaternowrisingbehindthemassiveThreeGorgesDam(SanxiaBa),IwasremindedofmyjourneydowntheLongRiveratatimewhenthedamwasunderconstructionandthemanycommunitiesalongtheriverstillexistedastheyhaddoneforhundredsofyears.TodaytheregionisattheheartofChina’smodernisationdriveandwillplayWiththerecentannouncementofthewaternowrisingbehindthemassiveThreeGorgesDam(SanxiaBa),IwasremindedofmyjourneydowntheLongRiveratatimewhenthedamwasunderconstructionandthemanycommunitiesalongtheriverstillexistedastheyhaddoneforhundredsofyears.TodaytheregionisattheheartofChina’smodernisationdriveandwillplay

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简介：ThecharacteristicsoftheTriassicsequencesdevelopedintheLowerYangtzeareadisplaysomegreatchangesinbothenvironmentandclimate.Thechangeofenvironmentwasatransitionfrommarinetocontinentviaalternatingenvironments.Thechangeofclimatewasatransitionfromtropic(torrid)towarmandwetclimateviasubtropicdryclimate.Thetypevariationsofthesequenceswerefromthemarinesequencestothecontinentalsequences,correspondingtothechangesofenvironmentsandclimates.Sequence1isatypeⅡofsequenceofmixedclasticandcarbonatesediments;sequence2isatypeⅠofsequenceofcarbonateplatform;sequence3isatypeⅠofsequenceofcarbonatetidalflat-saltlagoon,sequence4isatypeⅡofsequenceoflacustrinewithinmarinelayers,andsequence5isasequenceoflacustrine-swamp.Thedevelopment,distributionandpreservationofthosesequencesrevealthetectoniccontrolsandtheirchangesinthebackground.ThecollisionbetweentheYangtzeplateandtheNorthChinaplatewasagreatgeologicaleventinthegeologicalhistory,butthetimingofthecollisionisstilldisputed.However,thecharacteristicsofTriassicsequencestratigraphyandsealevelchangesintheLowerYangtzearearespondedtothiscoliision.ThecollisionstartedatthebeginningofmiddleTriassicandthegreatregressionintheLowerYangtzeareastarted22Maearlierthanthoseintheworld.Thetectonicconditionsoccurredbeforeandduringthecollisioncontrolledthedevelopmentofsequencesandtypechanges.

简介：Theexploitablepotentialofhydropowerresourcesinthe1,800,000km~2Yangtzebasinis197GW,correspondingtoanannualelectricitygenerationof1030TWh,whiletheupperYangtzeupstreamofthecityYichangwithdrainageareaof1,000,000km~2possessesanexploitablepotentialofhydropowerresourcesof170GWor85%ofwhatisinthewholeYangtzebasin,asriverchannelsofthemainstemandtributariesinuppeYangtzepassthroughhighmountains,plateausandhills.

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简介：ThehydrodynamicandthesedimenttransportpatternswithintheestuaryoftheYangtzeRiverarecomplexbecauseofinteractionoffluvialandthetidalforces,dependingonfreshwaterdischargeandtidalrange.Basedonthedatameasuredinrecentyears,thispaperdiscussesthecharacteristicsofflowandsedimentmovementintheYangtzeRiverEstuaryandtheirinfluencesontheevolutionoftheestuary.

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简介：Theso-called“Yangtze-type”copperdepositsinclude:（1）Cu-bearingmassivepyritebed,(2)Cu-bearingskarnandmagnetite-typeoredeposits,withreplacementCu-vein-typedepositsnearthemetasomaticzone,and(3)mineralizedintrusivebodiesandbrecciapipes,someofwhichareknownasporphyrycopperores(e.g.Chengmenshan).ThistypeoforedepositsisatypicalexampletoverifythepolygenesisofinostofthedepositsinChina,ashasbeenpromotedbyProf.TuGuangchiinviewofthepolycyclicdevelopmentofthegeologicalhistoryinChina.Thispaperiscon-cemedwithonesub-typeofsuchdeposits.

简介：<正>NanjingNO.2YangtzeRiverBridgewasanationalkeyconstructionprojectduringtheNinthFive-YearPlanperiod(1995-2000).Itislocated11kilometresupstreamfromthefirstYangtze

简介：BasedonthebiogeochemicalstudiesonnutrientelementsintheChangjiangestuary,themainresultsandrecentprogressesarereviewedinthispaper,suchasthenutrientfluxesintothesea,themixingbehaviors,thedistributioncharacteristicsandtransportationaswellasthebiogeochemicalbehaviorsofnutrientsintheplumefrontalregion.Theexploringdirectionsandresearchemphasesinthefutureareproposed.

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简介：Ｔｈｒｅｅｆｕｎｄａｍｅｎｔａｌｔｈｅｏｒｉｅｓａｒｅｒａｉｓｅｄｆｏｒ“ｃｏｍｐｌｅｘｉｔｙａｎｄｓｅｌｆ－ｏｒｇａｎｉｚｅｄｃｒｉｔｉｃａｌｉｔｙ（ＳＯＣ）ｏｆｍｅｔａｌｏｇｅｎｉｃｄｙｎａｍｉｃｓｙｓｔｅｍｓ”（Ｙｕ，１９９８）：（１）Ｎｏｎｌ...

简介：ThecircumfluencearoundtheJiuduanSandbankisthoroughlystudiedbymeansoftheprinci-pleofleastresistanceinfluiddynamics.ThediversionratiooftheNorthChannelfor1998iscalculated,whichisalmostthesameasthefieldsurveydata.ThenormalandminimumdiversionratiosoftheNorthChannelafterstagesⅠ,ⅡandⅢregulationworksaswellasthefuturephaseareobtained.Thenumeri-calresultsandpredictedvalueareaccurate.

简介：-ThispaperdescribesaradioactivetracerexperimentcarriedoutatthelandwardspoilsiteoftheNorthPassageintheYangtzeEstuaryinJune,1991.Scandium-46wasselectedasthetracer,thetotalactivityreleasedwas179.45GBqandtheamountoftheSandium-46glasswas495g.Thepurposeoftheexperimentwastodeterminethesedimentmovementdirection,path,velocityandtransportrate,andtherefore,toprovidedirectevidenceforusingthelandwardspoilsiteinthefuture.Theexperimentalresultsshowedthatthesedimentmovementwasgovernedbytheebbtidecurrentduringtheperiodofmeanandneaptideswhentheradioactivetracerwasinjectedbothonthefloodandebbtides,andthesedimentmovedfromthereleasepointtothemiddleoftheNorthPassagenearnavigationbuoyNo.269.Thedirecitonofthesedimentmovementwas110°,theparticlevelocitywas758m/d,andthesedimenttransportrateperunitwidthwas47.8m3/md.

简介：MultistagesuperimposeddeformationhasbeendiscussedsystematicallybasedontheprogressofthestratigraphicsequencesofthenortheasternmarginofYangtzeBlock.Thenew-discoveredfirststagedeformationofthosesequencesoccurredfromthemiddleTriassictotheendofearlyJurassictogetherwithdevelopmentofregionalfolding,whichwasresultedfromthedeepdetachmentshearingtendingtowardNW-WNW.Thefoldsdiptoeastandfalldowntowardwest,andweresuperimposedbythemainstagefolding.Thereafter,aseriesoffoldsweredevelopedwithaxestrendingtowardnortheast.Consequentlynormalfoldsoccurredonthenormallimbswhileoverturnedfoldontheoverturnedlimbsduringthefirststagefolding.ThedetachmentorthrustwasformedfromlateJurassictoearlyCretaceous.DuetotheupliftingofDabieandtheWannanMountainsinthenorthandsouthsides,thebi-directionalthrustingbeltwasformedbygravityflowingfromtheMountainstowardthecenterofthebasinalongthenorthsideofXuanchengandsouthsideofGuichi.Thedeformationgeodynamicswasdiscussedsimplybasedonthenewlyrecognizedinformationaboutthetectonicevolution.

简介：Throughoneandhalfyearcontinuousin-situmeasurements,thedistributionsandvariationsofsurfaceozoneanditsprecursorsatatypicalmixedagriculturalandmetropolitanarea-Changshu,YangtzeDeltaregion,werestudied.Thepreliminaryanalysisontheconcentrationlevelsandvariationsofsurfaceozoneindicatedtheobviousseasonalanddiurnalcyclesduringtheexperiment.Thehourlyaveragedconcentrationsofsurfaceozonewerehigh,inabout17%oftotalvalidhoursthesurfaceozoneconcentrationexceeded50ppb,andin22daysthehourlyaveragedozoneconcentrationwasgreaterthan100ppb.Therewereabout40%ofthedaysinthatthedailymaximum8-hourozoneconcentrationwasgreaterthan50ppb.Thedayswithdailymaximum8-hourozoneconcentrationgreaterthan80ppbwereabout33daysthataccountedforabout8%oftheobservationaldays.Thevariationsof5-daymovingaveragedozoneconcentrationsdependedbothontheweatherconditionsandonthechangesofozoneinbackgroundatmosphere.Photochemicalprocesshadthesignificantimpactsonozoneproductions.

简介：BasedonanalysesofsurfaceandcoresedimentsinthetidalflatsoftheYangtzeEstuaryandcoastalareas,thepresentstudyrevealsphosphorousformsexistinginsedimentsandtheirdistributions.Theresultsshowthatphosphorusintidalflatsedimentsinthestudyareamainlyconsistsofinorganicphosphorousforms,involvingDP,Fe-P,Al-P,andCa-Pandorganicphosphorousforms,inwhichCa-PandOParedominantcompositions.Thisfindingindicatesthatspatialdistributionsofvariousphosphorousformsarerelatedtosedimentaryenvironmentsinwaterandgrainsizesofsediments,andareinfluencedbysewagedischargesandeffluentsfromaquacultivationinthecoastalareas.

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