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1.
1 INTRODUCTIONTherecentandfuturedevelopmentofspacebasedremotesensingtechnologyhasbroughtareformationtoresearchworkaswellasformulatingsuitablepolicyforpopulation,resources,environmentanddevelopment.Throughrealtimeandperiodicobservationsofalargear…  相似文献   

2.
Urbanlandisthemaincarrierofhumandevelopment.Atthesametimelandisabasicmeansofproductivity.Urbanlandevolutionsensitivelyreflectstheprocess,tendencyandcontradictionofdevelopment.Thispaperfirsttheorizesthegeneralinterpretationonurbanlandevolution.The…  相似文献   

3.
CulturalgeographyinChinaisasubjectthathasevolvedfromtheancienttimesthroughmoderntimes,anddistinguishedachievementshavebeenaccomplishedduringallthisperiod(Wang,1991).Yetitisa“newlyestablished”inquiryinChinainthesensethatnosubstantialprogresshasbeenm…  相似文献   

4.
TheYarlungZangboRiver,alargeriverwithhighestaltitudeintheworld,2057kminlength,flowsthroughthesouthernpartoftheQinghaiXizang(Tibet)Plateaufromwesttoeastanddrainsanareaof240480km2beingasensitiveareatotheenvironmentalchanges(Guanetal.,1984;Yangetal.,…  相似文献   

5.
INTRODUCTIONAlthoughdescriptionoflifehistoryandestimatesofanimalproductionhavealonghistory (Lin degaard ,1 989) ,fewstudiesontheproductionrateofbenthicmacroinvertebrateswerecarriedoutinChinesewaters (Liang ,1 984 ) .Withthedevelopmentoffisheriesandthedeterioratio…  相似文献   

6.
I.INTRODUCTIONItisgeneralyacceptedthatthedegradationofrenewableresourcesandfragileenvironmentsindevelopingcountriesisbecomin...  相似文献   

7.
1INTRODUCTIONWiththerapiddevelopmentandapplicationofnewtechniquessuchascomputercartographyhasenteredthe21stcentury′sdigitalperiodfromcomputerassistmappinginthe1970straditionalmaprepresentationhastransformedfrom2Dmonomediumstaticinto3Dmultim…  相似文献   

8.
1 INTRODUCTIONBothresourceandenvironmentarerelativeconceptions,whicharerelativetothesystemstheyreferto.Theenvironmentofacertainarea(oracertainbusiness)ispossiblytheresourcesofthesurroundingareas(oranotherbusiness).Theatmosphere,waterbodiesandsoilont…  相似文献   

9.
Socalledfreeeconomicregionisaspecialregionwithoutjurisdictionofcustoms,delimitedbyonecountry.Inthisregionvariouspreferentialpoliciesofreducingorremittingtaxationareimplemented.Itcanprovidemanyconvenientconditionsforfreeflowofinternationalcommodity…  相似文献   

10.
I.INTRODUCTIONAtpresent,globalclimatechangehavebeenwidelypaidatentiontointernationaly.Climaticandenvironmentalchangesfromloc...  相似文献   

11.
TheintenseupliftoftheQinghaiXizang(Tibet)Plateauinthelastseveralmillionyearshasgivenrisetodrasticchangesofnaturalenvironmentanddistinctdifferentiationoftheplateauproperandtheneighborregions.Recentprogressinstudiesonpalaeogeographicalevolution,diff…  相似文献   

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

13.
The steps forward of GIS in China   总被引:2,自引:0,他引:2  
1 HISTORICALSTEPS—ATEMPORALANA LYSISResearchesofGISinChinacandatebacktotheearly 1980s .Atthattime ,aremotesensingapplica tionprojectwascarriedoutinSouthwestChinausingGISmethodintegratedwithremotesensingdatatosolvetheareameasurementautomatically .Afterthefir…  相似文献   

14.
1 CHANGESOFINDUSTRIALSTRUCTURE1.1 ChangesofStructureofThreeEconomicSectorsSincethereformofeconomicsystemandopeningtotheoutsideworldinthelate1970s,theindustrialstructureofGuangdongProvincehasbeenexperiencinganobviousprocessofnonagriculturalizationw…  相似文献   

15.
Dynamic variation of nitrogen content in the Second Songhua River   总被引:1,自引:0,他引:1  
ThewaterpollutionintheSecondSonghuaRiverhasbeenpaidmuchattentiontoforalongtime.Manyenvironmentalscientistshavedonealotofresearchworkonit,butmostofresearchcontentsweretofocusonheavymetalpollutionandorganicpollutioninwater,andlittleaboutnitrogen(Fuet…  相似文献   

16.
Landscape ecological construction and biodiversity protection   总被引:1,自引:0,他引:1  
Landscapeecology,producedbyaGermannamedC.Trollin1939,wenttoresurrectioninthe1980safterhavingwaveredforoverfortyyears,andnowithasbeenanimportant,complicatedandcomprehensivecrossdiscipline.Inthe21stcentury,thesocialsustainabledevelopmentwillbethemajo…  相似文献   

17.
1 INTRODUCTIONNowadaysthedevelopmentofworldindustriesandeconomyischaracteristicofafewconspicuoustrendswhichmaychallengetraditionaleconomicdevelopmentmodelsandtheories.Firstofall,theeconomyoftheworldhasbeenbecominginglobalspace,ofwhichtheremarkablei…  相似文献   

18.
Geothermalanomalyisaphenomenonthatundergroundtemperatureandgeothermalgradientincreasesmuchmoreintheareathanitssurroundings(Xia,1979).Abruptgeothermalanomalymeansthatundergroundtemperatureonsomespotsaswellastheaffectedtemperatureofsurroundingareaabr…  相似文献   

19.
1INTRODUCTIONSeverewaterpolutionandwaterresourcesshortageshavebecometwokeyobstructionstorealizesustainableutilizationofwate...  相似文献   

20.
Marriageisoneofthemostcommonestandoldestculturalphenomena,andalmostallmarriagesinvolvethemigrationofindividuals.Fromthispointofview,marriageisoneofthemostimportantfactorsthatresultinpopulationmigration.Afterreviewingallpreviousresearchesonpopulatio…  相似文献   

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