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1.
1 Introduction18Oinmarineenvironmentplaysanimportantroleinoceanographicalstudy .Asastableisotopeofoxygen ,18OtogetherwithhydrogenatomsconstituteswatermoleculeH218OandmoveswithalargeamountofH2 Omoleculesinseawater.Sothatδ18Obecomesanidealtracerforthemovemento…  相似文献   

2.
Global ocean tides from Geosat altimetry by Quasi-Harmonic analysis   总被引:2,自引:0,他引:2  
INTRODUCTIONOceantidesplayaveryimportantroleinthedynamicsoftheEarthandhaveattractedmanypeople’sattentionsinceancienttimes.Beforethelate 1 970s,tidesweremeasuredmainlybycoastalgauges .Directmeasurementsaswellasnumericalsimulations,canprovidefairlyaccurateu…  相似文献   

3.
INTRODUCTIONInrecentyears,co culture (integratedculture )ofmarinespecies (algaeandanimals)hasreceivedgreatattention .Inco culturesystemthealgaeactivelyuptakeCO2 andthemetabolicwastes(suchasNH4 +,NO2 - ,NO3- etc)asnutrientsources,andreleaseO2 tothesurroundingenviron …  相似文献   

4.
INTRODUCTIONInrecentyears,scientistspaidincreasingattentiontopolyploidybreedingofaquaticanimals.Studiesontriploidybreedingoffishandmolluschavemadenoticeableprogress.Therearereportsoflargescalecommercialcultureoftriploidsinducedinsomespecies.Thereported…  相似文献   

5.
INTRODUCTIONAtpresentgiantfreshwaterprawn (Macrobrachiumrosenbergii) ,Chineseshrimp (Penaeuschinensis)andgianttigerprawn (P .monodon)arethemainshrimpsforcultureinChina.Asweknow ,feedstuffcostisamajorexpenseiteminculturepractice.Overfeedingwillnotonlywastefee…  相似文献   

6.
INTRODUCTIONThevariousphysicalandchemicalreactionsthatoccurbetweenthesuspendedparticles,sediments,etc.andheavymetalsinanaturalaquaticsystemplayextremelyimportantpartsincontrollingthedistributionpattern,migrationandtransformationofheavymetalsthere.Since…  相似文献   

7.
A coupled interannual oscillation system   总被引:4,自引:0,他引:4  
INTRODUCTIONElNi no SouthernOscillation (ENSO)istheinterannualinteractionofocean atmosphereinthetropical(especiallyequatorial)Pacific .Itisalsorecognizedasbeingthedominantmechanismoftheearth’sinterannualclimatechange.Severalconceptual (simple)modelswereprop…  相似文献   

8.
INTRODUCTIONPhosphorusisakeynutritiveelementforthegrowthofmarinephytoplankton .Recently ,be causeofenvironmentalpollution ,theeutrophicationproblemsincoastalandoceanicwatershavebe comemoreandmoreserious.Theenvironmentecologicalresponseinthelong termtothef…  相似文献   

9.
1 INTRODUCTIONItisveryimportanttorealizethedistributionsofpollutantsbeforethepollutioncanbecontrolledsuc cessfully .Owingtothelackofsystematicalobserva tionsinabroadarea ,numericalsimulationhasbe comeapowerfultooltounderstandthedistributionsofpollutantsa…  相似文献   

10.
INTRODUCTIONTheeffectsofhumanactivitiesonshorelineprocesseshavebeenconsiderable,particularlyoverthelastcentury.Themostsignificanteffectsarethosefromharbourconstructionandrivermouthtrainingwall.Inmanyinstances,majorinterruptionoflittoraldriftresultedfro…  相似文献   

11.
INTRODUCTIONTheproductionofphytoplanktonisthefirsttacheintheproductionbymarineorganismsandinthemarinefoodchain .Knowledgeofprimaryproductioninmarinewatersisprerequisiteforexploitationandmanagementoftheocean’slivingresources.Theprimaryproductioninmarin…  相似文献   

12.
INTRODUCTIONRaninoidesfoundbyH .MilneEdwards,1 83 7,nowincludessixspeciesinIndo PacificOceans:R .personatusHenderson ,1 888,R .seratifronsHenderson,1 888,R .hendersoniChopra,1 93 1 ,R .barnardiiSakai,1 974 ,R .crosnieriRibes,1 989andR .intermediusDaietXu,1 993 .RecentlyreportedR .perso…  相似文献   

13.
1 INTRODUCTIONAsanimportantcomponentoftheglobalterres trialecosystems ,forestlinkstheatmosphere ,soilandwatertogetherthroughitspowerfulecologicalfunc tion .Inrecentyears,owingtotheglobalwarmingandhumaninfluence ,forestfireoccurmuchmorefrequently .Theannualf…  相似文献   

14.
INTRODUCTIONChlorinehastwonaturallyoccuringstableisotopes, 35Cland 37Cl.Severalstudiesreportedthevariationsintheisotopiccompositionofchlorineinnature.However,intheearlyyearsOwenandSchaeffer(1955)reportednoobservabledifferenceinthe 37Cl35Clratiosintensamplesex…  相似文献   

15.
1 IntroductionArcticclimateandenvironmentareveryimportantintheglobalchangesystems(WMO/UNEP 1 990 ;WMO 1 991 ) .Observationsandmodelingresultsindicatethattheglobalwarmingwillbeenhancedinthepolarregions ,especiallyintheNorthHemi sphere ,withapredictedwarmingofabout…  相似文献   

16.
INTRODUCTIONBiogenicsulfideproducedbybacterialsulfatereductionisoneofthemostimportantindicatorsinanoxicmarineenvironments,particularlyinconfiningbays,pollutedestuariesandaquaculturear eas.Theincreaseofitsconcentrationusuallyindicatesworsenedconditions.…  相似文献   

17.
INTRODUCTIONPollutionofmarineecosystemposesaseriousthreattomarineorganismsandultimatelytheentireecosystem.Inrecentyears,organophosphorous(OP)pesticideshavelargelyreplacedorganochlorinepesticidesbecauseoftheirrapidbreakdowninwaterandtheirlowenvironmenta…  相似文献   

18.
INTRODUCTIONTheBohaiSeawaschosenasthesiteofthefirstphaseoftheChina GLOBEC (GlobalOceanEcosystemDynamics)programfrom 1 997to2 0 0 0 ,inwhichthedynamicsofzooplanktonpopulationswasoneofthefourprincipalfoci.Smallcopepodscompriseanimportantcomponentofzooplanktonesp…  相似文献   

19.
INTRODUCTIONTraditionally,thecontinentalshelfcirculationisjudgedonthebasisofthewatersalinityandtemperaturedistribution,massanalysisandobservedcurrentvelocitybykinemometer.Limitedobservationaldatamakesitdifficulttodemonstratethecirculationmechanism.With…  相似文献   

20.
INTRODUCTIONJohannes (1 965)firstshowedtheimportanceofprotozoaasremineralizersinmarineenvironments.Thesignificanceofprotozoainthefreshwaterfoodwebhasbeenknownforthepast2 0years.Protozoaisamainpredatorofplanktonicbacteriaandphytoplankton ,andalsoafoodsourceo…  相似文献   

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