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1.
TlleupheavaloftheQingl1ai-XizangPlateauisolleoftl1ein1poltanteventsinnaturall1istoryd[lri11gthc1astsevcrall11illio11years.Correspondil1gx`ntl1t11euP]iftinaconsiderablelnagllitude,thePlateaul1asbeel1subjectedtodrasticchangesfrol11subtropica1el1vironn1entatlowaltitlldetofrigid/aridenvironmentatl1ig11altitude.Thecold/Wrmamplitudeofglobalclimatebringsaboutel1orl11ouschal1gesil1tllenatura1el1viro11l11el1t.Tl1efrigid-desiccatio11tel1del1cyhasbeenqlliteobvioussil1celaterperiodof1atePleistocene.The…  相似文献   

2.
TheLoessPlateauarealocatedinti1eMiddleReachesoftheYellowffiver(MRYR)isti1ecradleoftheCltinesenationandthesourceoftheancientcivilization.However,dun11galongpenodoftime,unreasonablelanduse,rapidpopulationgrowthandsenousmptiol1damagemadetheoriginalcriticaIenvirorunentevenworsened,deePlyichuencingtheeconowhcdeveloPmrmandtheimProvementoflocalpeople'slivingstandard.Thege0graplticalenvirorul1entisaco11unonandnecessaryextemalcondition.Wthsocialprogressandsciatificandtechnicaldevelopn1Cnt,theconn…  相似文献   

3.
I.Introductionl.BasicfcatUresofportcitiesandthcirwhuencingfactorsTl1elhstoricalexperiencesofdevelopedcowtrieshavewitnessedtheessel1tialro1eplayedbyseaportsinpromotingdevelopn1entofnationaleconomy.Manyportcities,emergodfron1marinetransportation,supportedbyseaandlandroLrtesandflourishedn1ainlythroughindustryandtrade,oftenbecomendonalornationalecononhccenters.fu11ongti1eworld's2Omeqalopolesofmorethan6ntilIionpopulation,l2areportcities.AlmosteverycoUntrywiti1coastalline,longorshort,roprdsoneors…  相似文献   

4.
ComparativehydrologyisthesciencedealingwithdifferentiationofhydrologicalphenomenaandinherentlawsofhydrologicaltyPesonthebasisofgnograPhy.Tllecomparativestudiesonstrea1llrunoffofEuropeandCl1ina11avebeendoneinthispaPerinordertodeepentheunderstandingofregionaldifferentiationandthecauseofforll1ationofstrea111nlnoffinbothregio11s.ThecomparisonbetweenChineseandEuropeanstreamrunoffcanalsogiveafurtl1erknoWedgeonChinesestreamrtl1offcl1aracteristic5andtheirinfltlenceo11l1u111a11.I.ComparisonorNatura…  相似文献   

5.
The Third National Assembly and Aid to Agricultural Comprehensive Scientific Annual Meeting of the Geographical Society of China was held in the latter half of November 1963 at Hangchow. More than 110 geographical workers from all over the country took part in the meeting. 343 scientific papers were received embracing achievements of studies in the fields of agricultural regionalization, physical regionalization, land  相似文献   

6.
WestCl1ina,includingSl1aallxi,Gansu,Qingl1ai,Sicl1uan,GuizhoualldYunnanprovinces,alol1gwitl1Xil1jial1g,NingXia,WesternlnnerMongolia,Tibetand'Gual1gxiautonon1ousregi0l1s,isintl1ei11teri0roftheEurasiancontinentandfarfromtllesea.ltcoversanareaof6.8lnilli0nsquarekl11,constitutillg69PercentofCl1ina'stotallal1darea.ltl1asapopulati0nofab0ut3OOl11illiol1,acco[lntingfor27Percent0ftllecountry'stotal,about5llllin0ritiesbesidesHansliveincompactc0l11l1lul1itieshereandthePOpulatiol1ofl11inoritiesis7…  相似文献   

7.
The Third National Assembly and Aid to Agricultural Comprehensive Scientific Annual Meeting of the Geographical Society of China was held in the latter half of November 1963 at Hangchow. More than 110 geographical workers from all over the country took part in the meeting. 343 scientific papers were received embracing achievements of studies in the fields of agricultural regionalization, physical regionalization, land  相似文献   

8.
LIntroductionThenorthwestemTibotanPlateaulvingbetweenWestKunlunandKarakorumMtsisoneoftl1eltigl1est(witi1meanelevationof5OOOm)anddriest(lessti1an2Olnna-'ofarulualprecipitation)areasofthePlateau.Itisalsoaunrecognizableplaceontl1ePlateau.Sincel973,ti1ell1tegratedScientificExpeditiontotheQinghai-Xizang(Tibetan)Plateau(ISEQP)organizedbytl1eCltineseAcademyofScienceshasmadegreatprogessinti1estudyoftl1euPliftingllistoryoftl1ePlateauanditsimpaCtontheenvirorunwtalchanges.Beforel982,ti1emainr…  相似文献   

9.
Mountain research is a comprehensive work. Its main contents are:1. the theory and the method of mountain rescarch;2. the comprehensive development. utilization and protection ofmountain resources:3. mountain calamities and their prevention and control:  相似文献   

10.
Over the past 15 years the linear learning machine has been applied to a large number of chemicalproblems.The learning machine approach is conceptually simple and does not require knowledge aboutthe statistical distribution of the data.However,there are problems associated with this approach.Oneproblem which has not been investigated is the influence of mislabeled samples on the positioning of thehyerplane in feature space.If a few samples in a data set are incorrectly tagged prior to training(i.e.thesamples are labeled as members of class 2 even though they are actually members of class 1),it is stilIpossible using the linear learning machine to achieve a classification success rate of 100% for the trainingset.However,unfavorable results will be obtained for the prediction set.The magnitude of this effect andits potential implications regarding the proper use of the linear learning machine are discussed.  相似文献   

11.
1.IntroductionThevaStterntoryandlongllistorymakeCllinaacountrypossessingnchtounsn1resource.Thelast15yearswitnessedarapiddevelopmentintounsmindustryofthecoUntry.Alotofhotelsandoti1erfacilitieshavebeenbuiltinthecoastalcitiesaswellasinil1einlandattraCtivesites.However,tounsminChina,asti1oseintheoti1ercotu1tries,isstillconfrcntedwiti1son1eproblemsWhiCh,ifnotproperlysolved,willhinderitsfutri1erdevelopinentlntbe,future.TheCO2-inducedglobalclimatechangeisoneoftheproblemsfacil1gh1efLturetounsm8ft…  相似文献   

12.
l.Introducti0nIntheseveraldecadestilltheendofthe1970s,therewasnoanyleastd0ubtthatChinahadbeenfollOwingabalancedregi0naldevelopmentstrategy.0bligedtotlledolnesticandinternationalsituationofthattime,capitalinvestlnentxvasn1ost1yf0rcedt0beputintotheundevel0pedarea(westeconomiczone),thisstrategyprovedtobelesseffectiveandincurredahugelossofinvestmentbenefit.Althoughthewestzoneisabundantinnatllralresources(mineral,energyresourcesetc.),thelevelofregionaldevel0pmentfromeastzonet0westzoneisgradua1lydec…  相似文献   

13.
I.ASurveyofNaturalConditionsKarakon1l1i-WestKul1l1l11Mtsissituatedi11thel1orthwesternpartoftheQinghai-Xizang(Tibetan)Plateau.Therearel1igl11llountains,deepandnarrowgorqe5.brondplateausandothercomplicatedlandforms.Characteristicsoflal1dfor1115nreaccountablefortl1eforl11atio11ofvario[1sverticaldistributiol1ofsoilspectrun1.1nthisrcgiol1,theclimatcisf;lgidaiidd1:Yi4it1ilitt1eprecipitatioi1.Gc,,c,d11,.pl'ecipitatio11i11plainareaatfootofthemountainsislessthanlOOmmbutitchangesalongwttl1variatio…  相似文献   

14.
TheNanshalslandsarethesouthetnmostterritoriesinChina.TheIslandsconsistof230islands,redandbeaches.Inthehistoricalperiod,theChineseancestorsovercamedifficutiesandfOundtheIslands2,0OOyearsago.Agreatmanyofhistoricalliteraturesindicatethatheeariiestrecords,mpa…  相似文献   

15.
I.Intr0ducti0nl.Backgr0undWenzhouisoneofthemostraPidlydevelopingcitiesinsouthernpart0fChina.Theoldcity0fWenzhou,whichhasahistoryofl600years,islocatedinthenorthernpart0fthecityalongOujiangRjver.Itc0versanareaofabout892hectares,including1lneighbourhoodswitl1atotalPOpulation0f340,959(l988).ItisoneofthehighlypoPlatedareasinChinawithaPOpulationdensity0f38,220peOPlePersquarekilometre.TheoldcityofWenzhouistl1ecommercialcentreofthenewWenzhoucity.Allldndsofactivitiesarelocatedonthelimitedlandwi…  相似文献   

16.
I.DynamicStI.uctureofRegioIlalUl.baIlizati0llRegionalurbanizationa11dregionaleconol11icdevelopl1lel1tarecloselyrelated.Tl1eprocessofregionaleconol11icdevelopmentisactuallytheprocessofurbangroWthandurbansystel11developn1ent.Regiol1alurbal1izatiol1isl1otonlythespatiall11anifestati0nofregionaleconolllicdeveloplllent,butalsothespatialmeanstofosterregiol1aleconon1icdevelopment.Tl1el11ajortheoriesofdeveloplnentec0nomicsanddeveloplllel1ttheoriesofregiollaleconon1icsaftertl1eSec0l1dWorldWarareall…  相似文献   

17.
1.IntroductionEnvironmentalrisk'isamajorenvirotunedlthreattothesustainabilityoftheropon.ItsanalysishasbecomeafOcusofenvironmentalstudyinthepastl0years.0win8torapideconothecdeveloPmentinChina,manykindsOfpotatialriskshavegreatlyhamPeredtheroponalsustainable…  相似文献   

18.
1.lntroduchollTllewte1prisesasanopensystel11iscol1nectedtoandil1teractswltI1nnextel11alenviIDnlnent.Allil1dustrialOIgnnizatiol1sexistinanenvi1-onl11entthatisbothcol11Plexanddynan1ic.Sincethelatel97Os,aseliesofecono111icreforl11shavebeeninitiated,andoPen-d…  相似文献   

19.
I.IntroductionTheuseofquantitative111odeIstodevelopUnderstanding,prePareforecastsandexplorepolicyoptionsinthecontextofurbanandroponaldevelpl11entremainsapopularaCtivlty,althouglrathermoresointheacadel11iccol11n1unitythanintl1epIanningprofession.However,thehistoryoftheapplicationoffon11aln1odelstopolicyproblemsdoesnotproducegreatconfidence.objeCtiveevaluationoftheuseofl11odelsinpolicyn1akingiscomplicatedbythefaCtthat,asafonl1ercolleagueoncesaid,con1puter111odeIsarelikecl1ildrenfmostpeopleten…  相似文献   

20.
I.IntroductionTlleYangtzeXiveroriginates0nthenorthernsideoftheTananlaMoulltail1ns0lltheQinghai-TibetPlateauinsouthwesternpartofQinghaiProvince,traversingacrosseightprovincesandanautonomousregionandfinallyPOuringintotheEastChinaSea.The638O-kilollleter-l0ngYallgtzeXivercoversadrainagearea0fl.8mi1lionkin'.0fthe53firstclasstributaries,26haveadrai1lageareaexceedinglO,OO0km2each.lnthevastdrainageareaoftheYangtzemver,tl1eeco-envir0nmentalconditi0nsdiffergreatlyfr0m0neregiontoan0ther.Topograp…  相似文献   

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