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1.
INTRODUCTIONTherearealotofpublishedpapersdescribingtheannualorseasonalendocrinechangesassoci atedwithreproductiveactivityinteleostfishes (Scottetal.,1 980 ;Louetal.,1 984 ,1 986;Suzukietal.,1 997;Hou 1 998;Yaronetal.,1 986) ,andevidencethatthegonadalmaturationofsalmo nidfishw…  相似文献   

2.
GAMMA-RAYS INDUCTION OF MUTATION IN CONCHOCELIS OF PORPHYRA YEZOENSIS   总被引:3,自引:0,他引:3  
INTRODUCTIONItisknownthatthereareseveraltypesofpigmentationmutantswithdifferentcolorascomparedwiththewildtypeinsomespeciesofPorphyra (Aruga,1 974 ;Miuraetal.,1 974 ;Miura,1 985) .InP .yezoensis,theyellowtypemutantwasobtainedinlaboratorybycrossingredandgreentypepigm…  相似文献   

3.
INTRODUCTIONContinentalshelfareasarereportedtohavehighproductivity (GuoandPan ,1 992 ;Furuyaetal.,1 998.,Ningetal.,1 988) .Eventhoughtheycompriseonlyasmallpartoftheworld’stotaloceanicarea ,theirproductivityaccountsforalargeproportionofthetotalprimaryproductivity(Wol…  相似文献   

4.
INTRODUCTIONRedtidesoccurredinXiamenHarborin1986and1987.Thelocalmarinescientistscloselyobservedtheseredtidesandobtainedmuchusefuldata(Zhangetal.,1988;Du,1989;Zhuang,1991;Chengetal.,1993).Butsimultaneoustransientwatermovementalwaysmadeitdifficulttoinvestigatetheseredti…  相似文献   

5.
INTRODUCTIONIntestinalparasitecommunitiesinfisharefoundnormallytobepoorintermsofspeciescompo sitionswhencomparedwiththoseinbirdsandsomeotherhighervertebrates (Kennedyetal.,1 986;Eschetal.,1 990 ) .However,ectoparasitecompositionsongillsoffishareconsideredasspec…  相似文献   

6.
INTRODUCTIONIncreasingattentionwasfocusedontheneedtostudythebacteriologyofmarinefishinChina ,becauseofbacteriaassociationwithhighmortalityinmarinefishcultureandconsequenteconomiclosstofishfarms (Dengetal.,1 996;Linetal.,1 999) .Vibriogenusbacteriahaveemergedast…  相似文献   

7.
INTRODUCTIONStudyofagreatquantityofsedimentsandhigh resolutionseismicprofiles (3 .5kHz)datacon firmedtheexistenceofalargeareaofmuddysedimentswhosedistribution ,formationenvironmentandoriginhadbeenstudiedbyvariousresearchers (Liuetal.,1 987;ParkandKhim ,1 990 ;Alexa…  相似文献   

8.
INTRODUCTIONCiliates,alwaysdominatingalltheprotozoans,arethecommonandimportantmembersoffreshwaterzooplanktoncommunities.Asmainconsumersofbacteria,picoplanktonandnannoplankton(Finlay,1978;Porteretal.,1985;Taylor,1984,1987;Simeketal.,1996)compriseanimportanttrophiclinka…  相似文献   

9.
INTRODUCTIONInmoststudies,growthrateoffishwasfoundtodecreasewithincreasingdensity ,especiallywhenthedensitywasaboveacriticalpoint (RefstieandKittlesin ,1 976;Refstie,1 977;Trzebia towskietal.,1 981 ;VijayanandLeatherland ,1 988) .However,inacold watercarnivorousfish ,theA…  相似文献   

10.
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   

11.
INTRODUCTIONThewesternboundarycurrents(WBC),counterundercurrentsobservedbelowthethermoclineincludetheMindanaoUndercurrent(MUC)beneaththeMindanaoCurrent(MC)(HuandCui,1989,1991;WangandHu,1998a,b;Wangetal.,1998)(Fig.1a),thesouthwardflowbelowtheKuroshio(hereinafter,KUC)(Huan…  相似文献   

12.
INTRODUCTIONAccumulatedevidencessuggestedaclosecorrelationbetweenneoplasticdiseaseofaquaticor ganismsandtheincreasingreleaseofgenotoxinsbyanthropogenicactivitiesintoaquaticenvironment(Mix ,1 986;Gardneretal.,1 991 ;GESAMP ,1 991 ) .Ithas,therefore,becomenecessarytoe…  相似文献   

13.
INTRODUCTIONWhiteSpotSyndromeVirus (WSSV)inPenaeuschinensisisthecausativeagentofaverysevereepizooticdiseasewhich,startingfrom 1 993 ,hadresultedinmorethan 80 %mortalitythroughoutshrimpculturefarmsinChina (Zhanetal.,1 995;1 998) .Now ,fiveyearslater,thevirusdiseaseissti…  相似文献   

14.
INTRODUCTIONItwasgenerallyconsideredpreviouslythatthecorrosionofsteelinseamudwasnotserious.However,itwaslaterfoundthatthecorrosionrateofsteelinsomeseamudwashigherthanthatinseawater(King,1980;Sehmide,1982;Guoetal.,1997;Hou,1998).Therearesomereportsthatthecorrosionr…  相似文献   

15.
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   

16.
INTRODUCTIONMuchefforthasbeenmadetowardsimulationoftheecosystemevolutionincoastalzone.Thefirstmathematicaldescriptionoftheseasonalplanktondynamics(Rileyetal.,1949)wasadvancedbytheecologicaltheoryontheregulationofpopulationsbycompetitionandpredatorpreyint…  相似文献   

17.
INTRODUCTIONEmpiricalorthogonalfunction (EOF)isastatisticalmethodwidelyusedtoquantitativelyexam inemeteorologicalandoceanicdata (PreisendorferandBarnett,1 977;Rasmussonetal.,1 981 ;KnappenbergerandMichaels,1 993 ;LeeandCornillon ,1 995) .Themethodseeksoutthefirstfeworth…  相似文献   

18.
1 INTODUCTIONWetlandcanperformenormousfunctionsinre sourceandenvironmentadjustment ,anditisoneoftheimportantecologicalenvironmentsthathumanbe ingsrelyon .Internationalcommunitieshavealreadypaid greatattentiontothewetlandresearch ,andsomeforeignershavedone…  相似文献   

19.
INTRODUCTIONThesinglecellsandprotoplastsofPorphyragametophytebladescoulddevelopintoplantletsdi rectlyorintocallus likecells (ZhaoandZhang ,1 981 ;Polne Fulleretal.,1 984 ;Chen ,1 989;WangandYan ,1 990 ;Galletal.,1 993;Chen ,1 997;MeiandFei,2 0 0 1 ) ,andtheirgrowthanddevelopmentunder…  相似文献   

20.
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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