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1.
I.IntroductionWeatheringbehaviourofrockmustbeviewedasbeingtheresultofinteractionbetweentheintrinsicpropertiesandexternalclimaticconditions[45].Mostreferencestofrostshatteringhaveemphasisedthedisruptiveforcesassociatedwiththephasechangesofwatertoice[1,26,34,3…  相似文献   

2.
I.TheTerracesoftheUpperYellowRiverTheterracesoftheupperYellowRiveraremostlydispersedalongthewidercoursesinseveralMesozoicCenozoicbasins(Figure1).1.TerracesbetweenNgoringLakeandGyaringLakeThesurfacelayersofthesedimentinthewideandshallowbasinswheretheYell…  相似文献   

3.
I.IntroductionTheacademic,scientificandpolicy-makingcommunitieshavefocusedconsiderableattentionontheconceptofsustainabledevelopment.FAO(1988)definessustainabledevelopmentas”themanagementandconservationofthenaturalresourcebase,andtheorientationoftechnologi…  相似文献   

4.
TheYarlungZangboRiverCanyon,whichencompassesMountNamjagbarwa,isoneofthefewmysticalforbbidenareasremainingonearthandishometomanyprofoundgeologicalandbiologicalmysteriesawaitingexploration.Inrecentyears,scientistsfromtheInstituteofGeographyandInstituteof…  相似文献   

5.
IntroductionBeijingisacityapartfromothers.Clearness,itsstatusastheChinesecapitalhasprovideditwiththisstandingfornearlyeightcenturiesinbothChinaandtheworld.However,explainingallthereasonsforthisremainsinherentlydifficult.Theobjectiveherethen,istounderlin…  相似文献   

6.
Atpresent,theMiddleEastisaregionoverwhichmanykindsofcontradictionsexist.Itisobviousthattherootcauseliesinitsimportanceinthestrategicgeographicalpositionandrichresourcesofoilandnaturalgas.Ithasalwaysbeenahotspotintheworld,andconflictshaveoccurredthereco…  相似文献   

7.
I.IntroductionDrylandcoverslargeareasinnorthernChinawithaboutonethirdofthecountry’stotalfarmlands,amongwhichrainfedfarmlandwithoutirrigationcovers2.3(107hm2.TherearethreekindsofdryfarmingareasinnorthernChina[9],i.e.subhumidandslightdryarea(aridity1.31.6,annualpr…  相似文献   

8.
I.ThePositiveRoleofBrown’sArticleAsaforeignscholar,Mr.L.Brownhasknownaseriesofdataandmaterialsonpopulation,foodproductivityandrelevantfactorsofChina,hadmaderatherdeepanalysisandgivenaforecastoffoodsecurityofChina.Hehasshownthepossibleserioussequenceinfo…  相似文献   

9.
IntroductionLanduserelatestohumanactivitiesinvolvingtheutilizationandmanipulationoflandandlandrelatedresourcestomeetthelivingdemandsofhumanbeingsforfood,fuel,shelter,etc.Landuse/landcoverchangesaretheimportantpartsofglobalwarming,aswellasthegapofintegra…  相似文献   

10.
I.Background1.NaturalconditionsTheirrigatedareaofnorthwestShandongProvincebychannelingYellowRiverisaveryimportantirrigatedregioninthelowerreachesofYellowRiver,including27countiesandcitieswithanareaof29,700km2,or19.3percentofthetotalofShandongProvince.Amongwhi…  相似文献   

11.
1 BackgroundXishuangbannaDaiPeopleAutonomousPrefectureislocatedinthesouthernpartofYunnanProvince,China.Thetotallandareais19223km2withpopulationof817772ofwhichareDai,Hani,Bulan,Lahu,Jinuo,Yao,Wa,andHanpeoplein.Theforestcoverageis63%.Thereareabout40000…  相似文献   

12.
ProfessorHuangBingweiwasbornin1913inthecityofHuizhou,GuangdongProvince.Geographyishischosendiscipline.AftergraduationfromtheSunYatsenUniversityinthesummerof1934,hewasgrantedaRockefellerFoundationfellowshipandjoinedtheGeologicalSurveyofChinatocarryoutstudie…  相似文献   

13.
ThevisitorsgivethecaveenvironmentagreatdealofCO2.AverageCO2contentofthevisitorsis13,00015,000ppminthebreedingandonevisitorbreeds40litreofCO2perhour.ThevisitorsstronglyinferencetheCO2contentinthecaveatmosphere.Inspring,CO2contentwas500-600ppminNo.1andNo.2chambersat8:008:…  相似文献   

14.
InChina,desertsmovingnorthwardduetotheupliftingoftheQinghai-TibetPlateauaredistributedinarid,semi-aridanddrysub-humidareasof35°-50°Nand75°-125°E.Deserts,GobianddesertificationaffectedareashorizontallycrossedNorthwest,NorthandNortheastChinainalengthof4,500km.Thev…  相似文献   

15.
I.LandDegradationDistributionandItsCharacteristicsThefarmingpastoraltransitionalregioninsemiaridlandofnorthernChinaisthemosttypicalregionoflanddegradation,andalsotheregionwithextensivelydevelopingsandydesertification.TheextentisfromHorqinSandyLandinth…  相似文献   

16.
I.ProgressofUrbanizationinChinaExperiencedFourStages1.19491957activeurbanizationperiodWhenthePeople’sRepublicofChinawasfoundedin1949,therewereonly132citieswithatotalurbanpopulationof39,490,000throughtoutthecountry.Thelevelofurbanization(referringtoratiosofthetotalp…  相似文献   

17.
Withanareaof1.2millionkm2,andanaltitudeof4000m,theTibetanAutonomousRegionconstitutesthemainpartoftheQinghaiTibetanPlateau,oneofthethreenaturalrealmsinChina.Itconsistsofaseriesofhighmountainsandhighlandswithmanywidevalleysandbasinssandwitchinginbetween.TheH…  相似文献   

18.
ThedeteriorationofecologicalenvironmentwhichhappenedinthemidstreamofNantingRiverhasseriouslyaffectedthepeople'slivingandworkingthere,sorestoring,protectingtheecologicalenvironmentandenvironmentsounddevelopmentandequitablyuseofthelocalresourcesofNanti…  相似文献   

19.
ThesupportingcapabilityofwaterandlandresourcesforsustainableincreaseofyieldinNorthChinaPlainZHANGHongyeInstituteofGeography,...  相似文献   

20.
ThemostprominentsignoflandscapeinirrigationoasesandnaturaloasesonriverbanksandalluvialfansindesertzoneofwesternChinaisthelushcultivatedornaturalwoodsinvividlygreencolor,whichisinremarkablecontrastwithyelloworgraycolorinotherdesertzones.Besidesshowingt…  相似文献   

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