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1.
Elementscyclingandenergyflowaretheimportantresearchcontentsinecosystemfieldsandresiduade-compositionisthekeyprocessofnutrimentalelementscirculationSWIFTetal.1979.Theresiduade-compositionrateplaysanimportantroleindecidingtheproductivityandbiomassof… 相似文献
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INTRODUCTIONAxeniccultureofalgaeisrequiredformanyexperimentalstudiesandcellsuspensioncultures,andisessentialforgainingunderstandingoftherelationshipbetweenthealgaeandtheirepiphyticfloraandmicroorganisms,andforstudyingthegrowthanddevelopmentofalgae (Tat… 相似文献
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毛连菊 《中国海洋湖沼学报》2000,18(3):283-288
INTRODUCTIONTheintracellularsurfaceofacellcouldbeobservedbyusingscanningelectronmicroscope(SEM)andthefreezefracturetechnique .Exposingthecellsurfaceisthemostdirectapproach .Inthistechnique,allexposedsurfacescutopenduringsectioningcouldbeviewedbySEM (Russ… 相似文献
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SUMMARY OF STUDIES ON CLOSED-POLYCULTURE OF PENAEID SHRIMP WITH FISHES AND MOLUSCANS 总被引:1,自引:0,他引:1
INTRODUCTIONTheworld’sshrimpcultureindustryhasbeensufferingfromviralepidemicdiseasesandfellintoadif ficultpositionforyears.Itisgenerallyacceptedtodaythatthediseaseswerecausedmainlybywaterpollu tioncreatedbyshrimpcultureitself,bothinshrimppondsandincoas… 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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INTRODUCTIONVariouscausativefactors,suchasincreasedscientificawareness,utilizationofcoastalwatersforaquaculture,eutrophicationandcysttransportation (Hallegreaffetal.,1 995)hasledtoextens ivestudiesontheglobalincreaseinHAB (HarmfulAlgalBloom) .YettheHABmechani… 相似文献
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1INTRODUCTIONWiththeaccelerationoftheeconomicglobaliza-tionthegradualshapingofthenewinternationaldivi-sionoflaborandthedevelopmentofthetransnationalcorporationstheworldurbansystemshavebegunanewroundofintegration.Ononehandthecitiesallovertheglobeare… 相似文献
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INTRODUCTIONTheKuroshioisthewesternboundarycurrentintheNorthPacificandisthecounterpartoftheGulfStreamintheNorthAtlantic.TheoriginoftheKuroshioisthenorthwardflowingbranchoftheNorthEquatorialCurrentwhichisdividedintotwocurrentsonapproachingthewesternbo… 相似文献
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INTRODUCTIONBillard ( 1 986)studiedthespermatozoonultrastructuresinteleostsandfounddistinctdifferencesa mongdifferentspecies.Studyonspermatozoonmorphologyandfunctionisachallengebecauseofthesperm’sspecialenvironment (Gageetal.,1 998;WangandZhang,1 999) .Sinceleft ey… 相似文献
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Todaysustainabledevelopmentiscurentlypromoted,butprohibitedbyfragileenvironment.Soinrecentyears,thestudyincludingformationre... 相似文献
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INTRODUCTIONKnowledgeofgametogenesisinvaluablemarineanimalsisveryimportanttocommercialfish ery.Gametogenesisinbivalveswasextensivelystudiedatdifferentlevels (Dohmen ,1 983 ;DorangeandLePennec ,1 989a,b) .Scallopsandothermarinebivalveshavesimilarreproductivecycle… 相似文献
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IMPACT OF WATER ENVIRONMENTAL CHARACTERISTICS IN DRY-HOT VALLEY OF JINSHA RIVER ON SOIL DESERTIFICATION 总被引:1,自引:1,他引:0
Withthesocialdevelopment,humanbeingshadtopaymuchatentiontothecrisisofenvironmentastotheeconomiccrisis.Waterdeficiencyanddeser... 相似文献
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EFFECTS OF HARVEST STAGE ON THE TOTAL LIPID AND FATTY ACID COMPOSITION OF FOUR CYLINDROTHECA STRAINS
INTRODUCTIONPeopleshowedgreatinterestsinmicroalgaeduetotheirgoodcharacteristics,suchashigheffi ciencyofusingsolarenergy,smallsize ,nutritionalvalue ,rapidgrowthandmultiplicationrate .Mi croalgaehaveanimportantroleinmaricultureasfoodforlarvalstagesofcrusta… 相似文献
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INTRODUCTIONJohannes (1 965)firstshowedtheimportanceofprotozoaasremineralizersinmarineenvironments.Thesignificanceofprotozoainthefreshwaterfoodwebhasbeenknownforthepast2 0years.Protozoaisamainpredatorofplanktonicbacteriaandphytoplankton ,andalsoafoodsourceo… 相似文献
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1INTRODUCTIONInecosystemfragileecoenvironmentisdefinedasthe“interface"betweentwoormoresystemsofmatterenergystructureorfunctionandthetransitionregionextendingfromthisinterfaceNIU1989.ThefragileecoenvironmentoftheSongnenPlainissitu-atedonsuch… 相似文献
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INTRODUCTIONFromthe1990’s,thescallop,C.farreri,culturedinthenorthernChinaSea,deterioratedinsize,healthandoutputbecauseofhighstockingdensities,shortageofnaturalfoodanddiseases.Massmortalityof50%-90%occurredinJiaozhouBay,Qingdao,andSishiliwanBay,Yantai,fromJulyto… 相似文献
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INTRODUCTIONTheproductionofphytoplanktonisthefirsttacheintheproductionbymarineorganismsandinthemarinefoodchain .Knowledgeofprimaryproductioninmarinewatersisprerequisiteforexploitationandmanagementoftheocean’slivingresources.Theprimaryproductioninmarin… 相似文献
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INTRODUCTIONJiaozhouBayisashallowsemi closedbaywithtotalareaofabout 40 0km2 andaveragewaterdepthof7m .Themaximumwaterdepthisover 5 0matthecenterofthestraitconnectingtotheYellowSea.Thisstraitcenterwateriscalledbaymouthwater,thewaterinthenorthernpartofthestrai… 相似文献
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张新长 《中国地理科学(英文版)》1999,9(3):265-273
1 INTRODUCTIONGuangdongProvincehasbeenwidelyknownasoneofthemostimportantindustrialbasesforexportinChina.IthasplayedanimportantroleineconomicreformanddevelopmentinChina.Inrecentyears,ithasattainedasustainableeconomicgrowthandkeptthefirstpositioninecon… 相似文献
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1 INTRODUCTIONItisveryimportanttorealizethedistributionsofpollutantsbeforethepollutioncanbecontrolledsuc cessfully .Owingtothelackofsystematicalobserva tionsinabroadarea ,numericalsimulationhasbe comeapowerfultooltounderstandthedistributionsofpollutantsa… 相似文献