简介:TheaimofthispaperistostudytheREEgeochemistryoftheShenzhenBay(SZB)andDapengBay(DPB)modernsediments,discusstheirREEdistributionpatterns,revealtheREEgeochemicaldifferencebetweenthetwobayswhichsharethesamematerialsourcebutaredepositedindifferentsedimentaryenvironments,andexpoundtheirdynamicchanges.ItcanbeconcludedthattheSZBandDPBsedimentsareessentiallyofcontinentalsource.TheirREEdistributionpatternsarequitedifferentfromthoseofPacificpelagicsediments,butareverysimilartothoseofSouthChi-nagranites.BecauseofdifferentsedimentaryenvironmentsprevailingintheSZBandDPB,someREEfractionationwouldhavetakenplaceinthesedimentsofthetwobays.
简介:Eightsetsofcoastalacoustictomography(CAT)systemsweredeployedduringNovember29toDecember10,2002atthecoastsonbothsidesofTokyoBaytomeasuretidalcurrentstructuresat15-mininterval.SoundtransmissionacrosstheTokyoBay(betweenYokohamaandChiba)wassuccessfullytraced,evenundersevereinterferencefromshipgeneratedwakesandbubbles.Tidalcurrentfieldschangingfromnorthwardtosouthwardflowarewellreconstructedbytheinverseanalysisoftravel-timedifferencedataforaperiodwiththebestsoundtransmissioncondition.ItissuggestedthattheCATisthemostpowerfultooltocontinuouslymaptidalcurrentfieldsinthecoastalseaswithheavyshippingtrafficandfisheriesactivity.
简介:Usingmeteorologicaldataoffieldobservationin1990~2000,especiallypolarorbithighresolutionNOAAsatellitecloudmapsreceivedfromtheAntarcticexpeditionvesselsince1997,theformationanddevelopmentofthePrydzBaycyclonearestudiedinthispaper.Somenewviewpointsaresuggestedsuchas:whensurround-polarcycloneentersthePrydzBay,itcanalsointensifyanddevelopinsummer;cyclonecanalsodevelopintheeasterliesinthisbay.TheseviewpointsreviseolduncompleteviewpointthatthePrydzBayisaburialgroundofcyclone,andalsofurtherconsummateformation-developmenttheoryofsurround-cycloneintheAntarcticwesterliesandcycloneintheAntarcticeasterlies.Inthispaper,themechanismofice-air-seainteractioninthePrydzBayisstudied,andthephysicalprocessofcycloneformation-developmentisexplained.Byuseofwhollydynamictransportationmethod,anenergyexchangecaseofacyclone,whichexplosivelydevelopedafterenteringthePrydzBay,iscalculated.Intheopenwaterarea,momentumfluxis-2.205N/m2,sensibleheatfluxis486.69W/m2,andlatentheatfluxis261.84W/m2.ItislargerthanvaluesofwesterliesburstoverthePacific.Theheattransferredfromoceantoatmosphereinformofsensibleandlatentheatpromotescyclonedevelopmentrapidly.Inthiscasewindforcewasasstrongas12grade,with10minutesaveragewindspeedof38m/s,andinstantaneouswindspeedof100m/swhichbrokethewindspeedrecordof96m/sintheAntarctic(WendlerandKodama).
简介:AcomprehensivefieldstudyhasbeenundertakentoinvestigatesedimentresuspensiondynamicsintheMoretonBay,alargesemi-enclosedbaysituatedinSouthEastQueensland,Australia.Aninstrumentedtripod,whichhousedthreecurrentmeters,threeOBSsensorsandoneunderwatervideocamera,wasusedtocollectthefielddataontides,currents,wavesandsuspendedsedimentconcentrationsatfoursites(Sites1,2,4,and5)inthebay.Site1waslocatedatthemainentrance,Site2atthecentralbayindeepwater,andSites4and5attwosmallbaysinshallowwater.Thebedsedimentwasfinesand(d50=0.2mm)atSite1,andcohesivesedimentattheotherthreesites.Basedonthecollectedfielddata,itisfoundthatthedominantdrivingforcesforsedimentresuspensionareacombinationofoceanswellandtidalcurrentsatSite1,tidalcurrentsatSite2,andwind-wavesatSites4and5.Thecriticalbedshearstressforcohesivesedimentresuspensionisdeterminedas0.079PainunidirectionalflowatSite2,and0.076Painwave-inducedoscillatoryflowatSite5.
简介:Analysisofmagneticpropertiesofmarinesurfacesedimentshasbeengraduallyprovedtobeoneoftheeffectivemeansforresearchingthesourceofmarinesediments.Inthispaper,samplesfrom39sitesinLiaodongBaywerecollectedtoanalyzethemagneticcharacteristicsofthesurfacesediments.MagneticstudyindicatedthatthesurfacesedimentsoftheLiaodongBayarecharacterizedbymagnetite.InthemiddleandeasternpartandthesouthwestcorneroftheBay,themainmagneticgrainswerecoarsemulti-domainandpseudo-single-domainparticles,whileinotherareassingle-domainandpseudo-single-domainparticlesconstitutethemajority.Basedongrainsizeandenvironmentalmagnetismdata,thecontentofmagneticmineralshasapositivecorrelationwiththehydrodynamicenvironmentwhenthemagneticmineraldomainisfiner.However,thecontentofmagneticmineralsisinacomplexrelationshipwiththehydrodynamicenvironmentinthecoarsemagneticdomainofmagneticmineralsfoundincentralLiaodongBayandplacesoutsidetheFuzhouBay,implyingthatthestronghydrodynamicenvironmentacceleratesthesedimentationofcoarsemagneticminerals.Basedongeographicpatternofmagneticproperties,itcanbeinferredthatthemainprovenanceofthesurfacesedimentsoftheLiaodongBayisthesurroundingrivers,andthecomparativeanalysisindicatesthatYellowRiversubstancesmaybealsoexistinthebay.
简介:在Bohai海湾的热带以外的暴风雨巨浪和淹没的一个二维的数字模型基于不稳定的流动海军司烧方程被造。模型包括了二节,一个人为暴风雨巨浪的模拟为在沿海的区域的暴风雨巨浪淹没的模拟的潮汐的水平和其它。当模仿暴风雨时,澎湃潮汐的水平,轮流出现的方向含蓄(ADI)方法被用于驱散并且解决2D暴风雨巨浪方程。在暴风雨巨浪淹没的模拟,2D不稳定的流动方程被驱散并且解决了使用有限体积方法(FVM)的无结构的格子。淹没和暴风雨巨浪的过程的Acoupling计算模式潮汐的水平变化被建议,当模仿并且预报暴风雨巨浪的过程时,因此,暴风雨巨浪淹没过程和区域能被计算潮汐的安装。而且,在Bohai海湾的热带以外的暴风雨巨浪和淹没用这个数字模型被模仿。模拟结果在对测量数据的好同意,它证明这个数字模型提供在Bohai海湾模仿并且预报暴风雨巨浪和淹没的一个新方法。
简介:Carbonmonoxide(CO)playsasignificantroleinglobalwarmingandatmosphericchemistry.GlobaloceansarenetnaturalsourcesofatmosphericCO.COatsurfaceoceanisprimarilyproducedfromthephotochemicaldegradationofchromophoricdissolvedorganicmatter(CDOM).Inthisstudy,theeffectsofphotobleaching,temperatureandtheorigin(terrestrialormarine)ofCDOMontheapparentquantumyields(AQY)ofCOwerestudiedforseawatersamplescollectedfromJiaozhouBay.Ourresultsdemonstratthatphotobleaching,temperatureandtheoriginofCDOMstronglyaffectedtheefficiencyofCOphotoproduction.Theconcentration,absorbanceandfluorescenceofCDOMexponentiallydecreasedwithincreasinglightdose.Terrestrialriverineorganicmattercouldbemorepronetophotodegradationthanthemarinealgae-derivedone.TherelationshipsbetweenCOAQYandthedissolvedorganiccarbon-specificabsorptioncoefficientat254nmforthephotobleachingstudywerenonlinear,whereasthoseoftheoriginalsampleswerestronglylinear.Thissuggeststhat:1)terrestrialriverineCDOMwasmoreefficientthanmarinealgae-derivedCDOMforCOphotoproduction;2)aromaticandolefinicmoietiesoftheCDOMpoolwereaffectedmorestronglybydegradationprocessesthanbyaliphaticones.WatertemperatureandtheoriginofCDOMstronglyaffectedtheefficiencyofCOphotoproduction.ThephotoproductionrateofCOinautumnwasestimatedtobe31.98μmolm-2d-1andthetotalDOCphotomineralizationwasequivalentto3.25%-6.35%ofprimaryproductioninJiaozhouBay.OurresultsindicatethatCOphotochemistryincoastalareasisimportantforoceaniccarboncycle.
简介:Thevariationsinnutrients(molarratios)andchlorophyllaintheJiaozhouBaywereexaminedbeforeandafteradiatombloominaperiodthatlastedfromNovember2003toMarch2004.Negativerelationshipsbetweennutrientconcentrations,Si/P,Si/Nratiosandchlorophyllacontentwerefoundduringthebloom,whichreflectedtherelationshipbetweennutrientconcentrations,phytoplanktonbiomassandgrowth.Largeincreaseinnutrientconcentrations,particularlySiO3-Siafterthelateautumn,isoneofmajorreasonsinducingthediatombloominwinter,andthebloomwasfinallycontrolledduetoSiO3-Sidepletionbyphytoplankton.ThebloomwasmainlycontrolledbySiO3-Si.Before1998,relativelylowlevelofSiO3-SikeptecologicalbalanceofeutrophicationwatersintheJiaozhouBay.Inrecentyears,however,humanactivitieshaveincreasedSiO3-Siconcentration,whichislikelyoneoftheprimarycausefortheincreaseddiatombloomsintheJiaozhouBay.Therefore,itisnecessarytocontrolSiO3-SiconcentrationintheJiaozhouBay.
简介:Themethodhasbeenestablishedtocalculatetheenvironmentalcapacity(ECo),surplusenvironmentcapacity(SECo)ofwaterwithrespecttomarinepetroleumhydrocarbonsassociatedwithoil(PHAOs)andtheself-purificationcapacity(SPCo)ofmainself-purificationprocesstoPHAOsintheJiaozhouBay,China,accordingtothedynamicmodelfordistributionofmarinePHAOsamongmultiphaseenvironments.ThevariationofconcentrationofPHAOsintheJiaozhouBayiswellsimulatedbythedynamicmodel.Basedonthemodel,theEC.,SEC.ofwaterwithrespecttoPHAOsintheJiaozhouBaywerecalculatedduringthelast10yearsunderthefirst-classandsecond-classqualitystandardrequirement,accordingtoSPCoofmainself-purificationprocesstoPHAOs.Theresultsshowthatabout200tonsofPHAOscouldbedischargedintotheJiaozhouBayformaintainingthefirstclassseawaterqualitystandard,andabout600tonsofPHAOsforthesecondclassseawaterqualitystandardlater.
简介:Basedonthedataobtainedduringthe15thAntarcticExpeditionofChinabetweenNovember1998andFebruary1999,thepaperdiscussesthewatermassesdistributedonbothsidesoftheContinentalWaterBoundary(CWB)aswellasthespacialvariabilityofthephysicalcharacteristicsofthecentrallocation,thefrontalwidth,thefrontalstrength,theverticaldepth,andtheverticalthicknessforCWB,Theaboveresultsarecomparedwiththeresultsfromthedataobtainedduringthe9thAntarcticExpeditionofChinabetweenDecember1992andFebruary1993,andthetemporalvariabiltiyofthosecharacteristicsisdiscussed.Inaddition,theinhomogeneityofthekinematiccharacteristicsandthepattermsofthedynamicheightsforthosewatermasseslocatedonbothsidesofCWBareillustrated.Asitispointedoutinthepaper,thetroughinthedynamicheightfieldisidentifiedwiththefrontallocationofCWBandtheoceaniccurrentshear.Furthermore,thedynamicreasonfortheupwellingofthecircumpolardeepwatercanbeunderstoodbytheexplanationdescribedinthepaper.
简介:Anobjectiveanalysisoftropicalcyclonetracksisperformed,withwhichthetracksof131tropicalstorms(TSs)in1972-2011areseparatedintothreetypesthatmovewest-,north-andnorthwestward,denotedasTypesA,BandC,respectively.TypeA(21TSsand16%oftotal)hastheorigininthesouthwesternBayofBengal,withtheTSinaunimodaldistributionasitsseasonalfeature,occurringmainlyinautumn;18ofthe21TSs(takingup90%)landmostlyonthewesternBaycoast(westof85°E);5%ofType-ATSsattainsthewindspeedof>42.7to48.9m/s.TypeAhaslittleornoeffectonTibet.TypeB(74TSs,56.6%ofthetotal)hasitspreferableorigininthecentralBayofBengal,withtheTSinabimodaldistributionasitsseasonalpattern.Thistypedenotesthetravelinthenorthinspring,withthelandfallof67ofthe74TSs(accountingfor91%)mainlyonthemiddlecoastoftheBay(85°to95°E),and19%oftheTSsreachingthewindvelocityof>42.7to48.9m/s,whichexertgreateffectonTibetanditisthisTStrackthatgivesstrongprecipitationonitswaythroughthisregion.TypeC(36TSs,27.5%ofthetotal)hasitsmainorigininthesouthernpartofthebay,andtheseTSsareformedlargelyinautumn,movinginthenorthwestdirection,and23ofthe36TSs(64%)landmostlyonthewesternBaycoast,lastingforalongertime,withalmostnoimpactuponTibet.
简介:Recentobservationssupportanemergingparadigmthatclimatevariabilitydominatesnutrientenrichmentincostaleco-systems,whichcanexplainseasonalandinter-annualvariabilityofphytoplanktoncommunitycomposition,biomass(Chl-a),andprimaryproduction(PP).Inthispaper,wecombinedobservationandmodelingtoinvestigatetheregulationofphytoplanktondynamicsinChesapeakeBay.Theyearwechoseis1996thathashighriverrunoffandisusuallycalleda’wetyear’.A3-Dphysical-biogeochemicalmodelbasedonROMSwasdevelopedtosimulatetheseasonalcycleandtheregionaldistributionsofphytoplanktonbiomassandprimaryproductioninChesapeakeBay.Basedonthemodelresults,NO3presentsastrongcontrasttotherivernitrateloadduringspringandthehighestconcentrationinthebayreachesaround80mmolNm-3.Comparedwiththenormalyear,phytoplanktonbloominspringof1996appearsinlowerlatitudeswithahigherconcentration.Quantitativecomparisonbetweenthemodeledandobservedseasonalaverageddissolvedinorganicnitrogenconcentrationsshowsthatthemodelproducesreliableresults.Thecorrelationcoefficientr2forallquantitiesexceeds0.95,andtheskillparameterforthefourseasonsisallabove0.95.
简介:JellyfishfishingisaspecialtypeoffisherythatmainlyexistsinsomecountriesofEastandSoutheastAsia.Chinahasthelargestjellyfishfisheryyieldintheworldwithanannualharvestofaround300thousandtons.LiaodongBayisthemostimportantjellyfishfisherygroundinChina.However,duetothehighbenefitsofjellyfishfishery,whichleadstoillegalandout-of-seasonjellyfishfishingoccurringeachyearinLiaodongBay.IllegaljellyfishfisheryinLiaodongBayisatypicalexampleofthetragedyofthecommons.Thekeyproblemisthatfishermenseektoanillegallyinitiatejellyfishfishingasearlyaspossible.Inthispaper,basingonthedataofediblejellyfish’sbiologyandecology,wemainlyanalyzedthehistoryofjellyfishfisheryinChina,especiallyinLiaodongbay,andthenwecalculatedthecarrycapacityofediblejellyfishinLiaodongBaywhichisabout300thousandtonsoneyear.ThisnumberisequaltotherecentannualyieldofediblejellyfishinChina.Furthermore,basingonthecarrycapacityandreasonablequotaspriceanalysis,wesetupaJellyfishfishingquotasanddeficitquotasbuybacksystemwhichcouldbeasuitableandeffectivesolutionforjellyfishfisherymanagementanddevelopmentinLiaodongBayattheunderlyingroots.AlthoughChinaisthefirstcountrywithediblejellyfishaquaculture,theannualyieldofjellyfishaquacultureisonlyonefifthofjellyfishfishing.So,thereisaverybrightdevelopingprospectaboutediblejellyfishaquacultureinChina.
简介:Oneearlymorningintheearlyspring,greetingtherisingsun,wesetoffbycarfromHaikou,capitalofHainanProvinceanddroveabout90kmtoreachQinglanPortandthenbumpedalongadirtroadtowardsthesecludedCoconutPalmBay.