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1 IntroductionArcticclimateandenvironmentareveryimportantintheglobalchangesystems(WMO/UNEP 1 990 ;WMO 1 991 ) .Observationsandmodelingresultsindicatethattheglobalwarmingwillbeenhancedinthepolarregions ,especiallyintheNorthHemi sphere ,withapredictedwarmingofabout… 相似文献
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INTRODUCTIONItisknownthatthereareseveraltypesofpigmentationmutantswithdifferentcolorascomparedwiththewildtypeinsomespeciesofPorphyra (Aruga,1 974 ;Miuraetal.,1 974 ;Miura,1 985) .InP .yezoensis,theyellowtypemutantwasobtainedinlaboratorybycrossingredandgreentypepigm… 相似文献
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1 MathematicModelofTidalVibrationSupposethat 3semi -axesofaellipsoidarea ,bandc (a >b >c) ,latitudeisθ ,longitudeisψ(changingfrom 0°to 90°) , 相似文献
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利用SSR标记分析广西凡纳滨对虾育种中心选育的凡纳滨对虾品种中抗传染性皮下及造血组织坏死病毒(IHHNV)家系的遗传多样性,为凡纳滨对虾抗IHHNV育种亲本材料的选择提供参考。通过体外攻毒试验,从育种中心构建的凡纳滨对虾家系中筛选出抗IHHNV的家系,然后利用SSR标记对筛选出的抗IHHNV品种的遗传多样性进行分析。结果表明,6对引物在上述抗病毒品种中共检测到162个等位变异,每对引物平均为3个,引物的多态信息含量(PIC)在0.372 8~0.479 7之间,平均为0.434 1;抗病品种间的遗传相似系数平均为0.894 2,表明筛选出的抗病品种遗传多样性较高。 相似文献
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INTRODUCTIONAccumulatedevidencessuggestedaclosecorrelationbetweenneoplasticdiseaseofaquaticor ganismsandtheincreasingreleaseofgenotoxinsbyanthropogenicactivitiesintoaquaticenvironment(Mix ,1 986;Gardneretal.,1 991 ;GESAMP ,1 991 ) .Ithas,therefore,becomenecessarytoe… 相似文献
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INTRODUCTIONMyxosporeansareverycommonparasitesoffish .Theirseasonalfluctuationsinprevalenceandintensityofinfectionweredescribedbysomeauthors (Mitchell,1 989;Sitja BobadillaandAlvarez Pellitero,1 990 ;Cone ,1 994 ) .However,almostnorelatedinformationisavailableinChin… 相似文献
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INTRODUCTIONMorethanadecadehaspassedsincebacteriawasrecognizedasquantitativelyimportantcon sumersoforganiccarboninmarinefoodwebsandmarineecosystems (Fuhrman ,1 992 ) .ThebasicinformationonthesignificanceofthemicrobialfoodwebwaspresentedbyPomeroy ( 1 974 ) ,whopie… 相似文献
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PRELIMINARY STUDY ON THE FORMATION MECHANISM OF COUNTER WESTERN BOUNDARY UNDERCURRENTS BELOW THE THERMOCLINE——A CONCEPTUAL MODEL 总被引:1,自引:0,他引:1
INTRODUCTIONThewesternboundarycurrents(WBC),counterundercurrentsobservedbelowthethermoclineincludetheMindanaoUndercurrent(MUC)beneaththeMindanaoCurrent(MC)(HuandCui,1989,1991;WangandHu,1998a,b;Wangetal.,1998)(Fig.1a),thesouthwardflowbelowtheKuroshio(hereinafter,KUC)(Huan… 相似文献
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INTRODUCTIONTaoandChen (1 987)werethefirsttopointoutthattheAsiansummermonsooniscomprisedoftwosystems:EastAsiansummermonsoon (EASM )andSouthAsiansummermonsoon (SASM) .Theyaredistinctlydifferentfromeachotherinbothlarge scalestructureandconstituentsubsystems.Ther… 相似文献
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INTRODUCTIONThelargeyellowcroakerPseudosciaenacroceaoncewasoneofthefourimportantmarinefish eryobjectsinChina (Hongetal.,1 983;HuangandCarl,1 983;ChenandGong ,1 983) .TheproductionofthewildP .croceain 1 974reached 1 971 78metrictons (MT)inChina (Li,1 998) .Becauseofoverfishing ,th… 相似文献
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ZOOPLANKTON COMMUNITY STRUCTURE OF THE SEA SURFACE MICROLAYER NEAR NUCLEAR POWER PLANTS AND MARINE FISH CULTURE ZONES IN DAYA BAY 总被引:1,自引:0,他引:1
INTRODUCTIONTheseasurfacemicrolayer (SM)withspecialphysical,chemicalandbiologicalproperties,hadbeenwelldescribedasasiteofintensiveaccumulationofdissolvedandparticulateorganicmat terinvolvingphytoplanktonandbacteria (Hardy,1 982 ) .Thisenvironmenthasgreatimpor… 相似文献
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INTRODUCTIONEmpiricalorthogonalfunction (EOF)isastatisticalmethodwidelyusedtoquantitativelyexam inemeteorologicalandoceanicdata (PreisendorferandBarnett,1 977;Rasmussonetal.,1 981 ;KnappenbergerandMichaels,1 993 ;LeeandCornillon ,1 995) .Themethodseeksoutthefirstfeworth… 相似文献
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INTRODUCTIONTheSouthChinaSea(SCS)isapartly enclosedoceanbasinoverlaidbyapronouncedmonsoonsurfacewind .Paststudies (Chenetal.,1 991 ;DingandMurakami,1 994 ;Yan ,1 997;LiangBiqi,1 991 ;LiangJianyin ,1 991 )indicatethatahugewarmwaterpooljointlycontributedbythewesternPacific ,ea… 相似文献
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1 IntroductionTheafternoonregion (approximately 1 4 0 0to 1 60 0MLT)hasaspecialsignificanceforavarietyofmagnetosphericphenomena.Itsproximitytomagneticnoonsuggeststhattheauroralphenomenaobservedmayberelatedtodaysidemagnetosphericprocesses ,andindeedavarietyofstu… 相似文献
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INTRODUCTIONPenaeusjaponicusisaneuroxybioticpenaeidprawn ,whosepropersalinityrangeforgrowthis2 0 -30andoptimalsalinityrangeis 2 5-30 (WangandLiu ,1 991 ;WangandYu ,1 999) .Ithasgreatosmoregulatiorycapacity (MantelandFamer,1 983) .Butitsbestenvironmentforreproductionanddevel… 相似文献
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INTRODUCTIONColloids (orsub micrometerparticles)areoperationallydefinedasparticlesbetween 1nmand1 μm (Vold ,R .D .andVold ,M .J.,1 983) .Thedistributionbetween“dissolved”and“particu late”phaseinaquaticchemistryusedtobedefinedbyafiltrationwith 0 .45 μmporesizefilters.Th… 相似文献
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1 INTRODUCTIONTheterm“anastomosingriver”wasfirstappliedbySCHUMM ( 1968) ,referredtostable ,lowbed load ,multiplechannelsystemwithlow gradient,highsinuosityandseparatedvegetatedislands .Thisspecificmeaningon“anastomosis”whichwasfirstusedbyJacksonin 1834endedthesy… 相似文献
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PRELIMINARY STUDY ON THE DISSOLVED AND COLLOIDAL ORGANIC CARBON IN THE ZHUJIANG RIVER ESTUARY 总被引:3,自引:0,他引:3
INTRODUCTIONEstuariescompriseamajorbiogeochemicalinterfaceconnectingthelandandthesea (Man toura,1 987) .Thebehaviorandfateofaparticularriver bornesubstanceintroducedintoanestuaryisdeterminedtoalargeextentbythebiogeochemicalpropertiesofthesubstanceaswellasp… 相似文献
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INTRODUCTIONUrechisanimalsareoftenpresentinH2 Srichseaareawheremostanimalscannotlive .ItcantoleratethestrongtoxicityofH2 S .ManyscholarswereinterestedinthetoleratingmechanismofH2 SintheUrechisanimal (PowellandArp ,1 989;Arpetal.,1 992 ) .Arpetal.(1 992 )indicatedthatthe… 相似文献