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1.
INTRODUCTIONVariouscausativefactors,suchasincreasedscientificawareness,utilizationofcoastalwatersforaquaculture,eutrophicationandcysttransportation (Hallegreaffetal.,1 995)hasledtoextens ivestudiesontheglobalincreaseinHAB (HarmfulAlgalBloom) .YettheHABmechani…  相似文献   

2.
INTRODUCTIONMicrocystisaeruginosawasthemainbloom formingspeciesinDonghuLake;occurredonlysporadicallyinthe 1 950s,increasedrapidlyinnumberinthe 1 960s.Fromthemiddleofthe 1 970stothemiddleofthe 1 980s,thicklayerofitsbloomcoveredthelakesurfaceeverysummer,attract ingfo…  相似文献   

3.
INTRODUCTIONIncreasingattentionwasfocusedontheneedtostudythebacteriologyofmarinefishinChina ,becauseofbacteriaassociationwithhighmortalityinmarinefishcultureandconsequenteconomiclosstofishfarms (Dengetal.,1 996;Linetal.,1 999) .Vibriogenusbacteriahaveemergedast…  相似文献   

4.
INTRODUCTIONAccumulatedevidencessuggestedaclosecorrelationbetweenneoplasticdiseaseofaquaticor ganismsandtheincreasingreleaseofgenotoxinsbyanthropogenicactivitiesintoaquaticenvironment(Mix ,1 986;Gardneretal.,1 991 ;GESAMP ,1 991 ) .Ithas,therefore,becomenecessarytoe…  相似文献   

5.
INTRODUCTIONStudiesonphosphorusmetabolisminfarmedspecieshavebecomeapopularresearchsubjectrecently ,duetotheincreasedpublicconcernontheimpactofphosphorusdischargefromlivestockandaquaculturesystemsontheenvironment (Skonbergetal.,1 997;EyaandLovell,1 997) .Phosph…  相似文献   

6.
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   

7.
THE RESUSPENSION RATE OF SEDIMENTS IN 32°N SECTION ON THE EAST CHINA SEA   总被引:1,自引:0,他引:1  
INTRODUCTIONThe“greenhouseeffect”resultingfromtheincreasingcarbondioxideintheatmospheresignifi cantlyaffectstheglobalaveragetemperature (Deter,1 978) ,hasdrawntheattentionofscientistsaroundtheworld .Scientistsconsiderthatknowledgeoftheocean’scapacitytoabsor…  相似文献   

8.
I.INTRODUCTIONTheglobalaveragesurfaceairtemperatureoftheearthhasincreasedbyabout0.5℃sincethemid19thcentury(Houghtonetal.,19...  相似文献   

9.
INTRODUCTIONInrecentyears,scientistspaidincreasingattentiontopolyploidybreedingofaquaticanimals.Studiesontriploidybreedingoffishandmolluschavemadenoticeableprogress.Therearereportsoflargescalecommercialcultureoftriploidsinducedinsomespecies.Thereported…  相似文献   

10.
INTRODUCTIONBiogenicsulfideproducedbybacterialsulfatereductionisoneofthemostimportantindicatorsinanoxicmarineenvironments,particularlyinconfiningbays,pollutedestuariesandaquaculturear eas.Theincreaseofitsconcentrationusuallyindicatesworsenedconditions.…  相似文献   

11.
1INTRODUCTIONGeothermalanomalyisaphenomenonthatunder-groundtemperatureandgeothermalgradientincreasesmuchmoreintheareathanitssurroundingsXIA1979.Thisisanormalglobalphysicalphenomenonintheactiveandthelatentvolcanicarea.Duringthewarningsignperiodofan…  相似文献   

12.
1 INTRODUCTIONInrecentyearstheecoenvironmentoftheChangjiangRiverbasinsufferedfromseveredestruction,sedimentcontentintheriverwatergreatlyincreased,thedownstreamcoursewasseriouslysiltedupandfloodcontrolcapacitywasweakened.Thesimilarsituationalsooccu…  相似文献   

13.
INTRODUCTIONBiofoulingcancauseroughnessofsubmergedsurfacesofmarinestructures(Chakrabarti,1991),increasehydrodynamicloadings(WolframandTheophanatos,1985),acceleratecorrosionprocess(Patiletal.,1988),andimpedeunderwaterinspectionandmaintenance(Houghton,1978).Thelackofd…  相似文献   

14.
I.POPULATIONDISTRIBUTIONCHARACTERISTICSBytheendof1994,thepopulationofGuangzhouCityhadincreasedto3.803milion,apopulationsizera...  相似文献   

15.
1 IntroductionInthepastdecadesnumberofstudiesinvestigatedmicrocracksinrockshasrapidlyincreased .MicrocrackhasbeendefinedbyRichter  相似文献   

16.
1 IntroductionArcticclimateandenvironmentareveryimportantintheglobalchangesystems(WMO/UNEP 1 990 ;WMO 1 991 ) .Observationsandmodelingresultsindicatethattheglobalwarmingwillbeenhancedinthepolarregions ,especiallyintheNorthHemi sphere ,withapredictedwarmingofabout…  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.
INTRODUCTIONColloidsareabundantinseawater(Koike,1 990 ;WellsandGoldberg,1 991 ;1 992 ) ,andalargefrac tionofdissolvedorganiccarboninseawateriscolloid.Thisfractionofdissolvedorganiccarbonplaysanim portantroleinthebiogeochemicalcyclingoforganiccarbonandtracemetalsin…  相似文献   

19.
INTRODUCTIONTheproxyofstableoxygenisotopeinlakecarbonateisidealforthereconstructionofpastcli mate (Gasseetal.,1 991 ;Wu ,1 996;Zhangetal.,1 994 ) .Asidefrombeingimpactedbylake watertemperature ,thevalueofδ18Oinlakecarbonateisalsocontrolledbythatofambientlakewa ter.High…  相似文献   

20.
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   

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