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1.
I.INTRODUCTIONItisgeneralyacceptedthatthedegradationofrenewableresourcesandfragileenvironmentsindevelopingcountriesisbecomin...  相似文献   

2.
INTRODUCTIONAccumulatedevidencessuggestedaclosecorrelationbetweenneoplasticdiseaseofaquaticor ganismsandtheincreasingreleaseofgenotoxinsbyanthropogenicactivitiesintoaquaticenvironment(Mix ,1 986;Gardneretal.,1 991 ;GESAMP ,1 991 ) .Ithas,therefore,becomenecessarytoe…  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.
刘塔URBANRENEWALANDDEVELOPMENTOFSHANGHAICITY¥LiuTa(NanjingInstituteofGeographyandLimnology,theChineseAcademyofsciences,Nanjing2...  相似文献   

5.
INTRODUCTIONAxeniccultureofalgaeisrequiredformanyexperimentalstudiesandcellsuspensioncultures,andisessentialforgainingunderstandingoftherelationshipbetweenthealgaeandtheirepiphyticfloraandmicroorganisms,andforstudyingthegrowthanddevelopmentofalgae (Tat…  相似文献   

6.
1INTRODUCTIONJianghanPlainisoneoftheimportantbasesofChina′sagriculturalproductivitylocatedinthemiddleChangjiangRivervalleyofcentralChina.TheJianghanplainapproximately6.6×104km2inareaandover30millioninpopulationistherenowned“countryoffishandrice"in…  相似文献   

7.
INTRODUCTIONThemainpurposeofthisstudywastodeterminethemagnitudeandfrequencyofharmfuldiatomanddinoflagellateoutbreaksinHongKong’swesternandeasternwaters (e .g.LammaStraitsandPortShelterrespectively)fortheperiodJanuary 1 997toDecember1 999.Thiswasdoneinordertod…  相似文献   

8.
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   

9.
INTRODUCTIONThevariousphysicalandchemicalreactionsthatoccurbetweenthesuspendedparticles,sediments,etc.andheavymetalsinanaturalaquaticsystemplayextremelyimportantpartsincontrollingthedistributionpattern,migrationandtransformationofheavymetalsthere.Since…  相似文献   

10.
1INTRODUCTIONNoonecandoubtthatoneofthemostexcitingsoundsinnineteenthcenturyAmericawasthewhistleofalocomotive.ThroughoutthewholecenturyespeciallyinthesecondhalfrailroadsplayedadramaticroleintransformingtheAmericanwestfromabarrenlandintoapopulatedone…  相似文献   

11.
INTRODUCTIONTheHuangheRiverwellknownworldwideforitshighsedimentdischargeisChina’ssecondlargestriver,whoserunoffismainlysuppliedbyprecipitationovertheupperreaches.However,thematerialfromsoilerosionintheLoessPlateauinthemiddlereachesisamajorcontributort…  相似文献   

12.
THEEFFECTSOFTHETHREEGORGESPROJECTONECOLOGYANDENVIRONMENTXiaYicheng(夏宜铮)(InstituteofHydrobiology,theChineseAcademyofSciences,W...  相似文献   

13.
I.INTRODUCTIONCitiesarethesymbolsofhuman’scivilization,thespatialcariersofeconomyandthesourcesofregionaleconomicactivities(Gu...  相似文献   

14.
Elementscyclingandenergyflowaretheimportantresearchcontentsinecosystemfieldsandresiduade-compositionisthekeyprocessofnutrimentalelementscirculationSWIFTetal.1979.Theresiduade-compositionrateplaysanimportantroleindecidingtheproductivityandbiomassof…  相似文献   

15.
INTRODUCTIONFromthe1990’s,thescallop,C.farreri,culturedinthenorthernChinaSea,deterioratedinsize,healthandoutputbecauseofhighstockingdensities,shortageofnaturalfoodanddiseases.Massmortalityof50%-90%occurredinJiaozhouBay,Qingdao,andSishiliwanBay,Yantai,fromJulyto…  相似文献   

16.
INTRODUCTIONLimnodrilushoffmeisteri,aubiquitoustubificid ,isapredominantbenthicinvertebrateinmostshalloweutrophiclakesinChina (Liang,1 979) .Sofar,therearenodataonthesecondaryproduc tionofthiswormandfewdataonthatofotherzoobenthosreportedinChina .Withthefisher…  相似文献   

17.
1 INTRODUCTIONBothresourceandenvironmentarerelativeconceptions,whicharerelativetothesystemstheyreferto.Theenvironmentofacertainarea(oracertainbusiness)ispossiblytheresourcesofthesurroundingareas(oranotherbusiness).Theatmosphere,waterbodiesandsoilont…  相似文献   

18.
1INTRODUCTIONAtpresent,theresearchofnaturaldisastershasgotadvancesintimesequence,butitdevelopsslowlyinspacesequence,especialy...  相似文献   

19.
INTRODUCTIONTheeffectsofhumanactivitiesonshorelineprocesseshavebeenconsiderable,particularlyoverthelastcentury.Themostsignificanteffectsarethosefromharbourconstructionandrivermouthtrainingwall.Inmanyinstances,majorinterruptionoflittoraldriftresultedfro…  相似文献   

20.
1 IntroductionAlongwiththearrivalof2 3rdsolaractivepeakandthedevelopmentofthespacesci ence ,thescientistsaremoreandmoreinterestedintopicsofgeospaceeffectscausedbytheintensesolaractivities.Thegeospaceeffectsofseveralextremesolaractiveevents,suchasthe 1 993No…  相似文献   

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