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简介:IntroductionAlongwithintegratedregionalcooperation,interegionalasociationhasbenthemainpartofregionaleconomicdevelopmentinsome...
简介:Basedupontheformationandevolutionofoasisandthefactorsrestrictingthecoordinateddevelopmentofoasiseconomyandenvironment,thispaperpresentsagoalofthedevelopmentincoordination.Itsuggeststhatthesustainablesurvivalanddevelopmentofoasiscouldbeensuredonlyiftheoasis-desertandwatersourceecologyaremanagedinacombinedwaytoformamacrosystem.Inlightwiththeabovementioned,theapproachtothedevelopmentofeconomyandenvironmentofoasisinaridareashoulddependupontheestablishmentofanoasisecologicalandeconomicsystem,whichsuitsthearidenvironmentandpromotestheefficiencyofresourceconfiguration,stabilizeseconomicincrementandbenefitsecologicaldevelopment.
简介:在Bashang区域的自然条件被容易被自然灾难影响并且加强了人的活动的带的转变描绘。极其易碎的eco环境也是容易的把desertification形成并且发展。在从1978~1996的18年里,在地图的范围以内的Bashang的desertified陆地区域将近加倍,2199.11km的全部的增加,每年平均122.17km2的增加。而且,严重,desertified区域很快增加。在Bashang的陆地desertification是自然因素和荒谬的人的经济活动的联合结果。栽培陆地扩大,人口生长,和过度放牧的aggrevatedesertification开发。
简介:I.DevelopmentSituationTheregionalongtheYangizeRiveristhenationalmajorexploitationbeltandthebondoftheeasternandwesternpartsofC...
简介:I.InternationalRiversandtheLancangMekongRiverInternationalriversaredefinedastheriverswhichflowacrostwoortwomorecountries.Upt...
简介:ThispaperexaminestheexperimentalstudyoninfluenceofmaterialcomponenttononlinearrelationbetweensedimentyieldanddrainagenetworkdevelopmentcompletedintheLab.Theareaofflumedrainagesystemis81.2m2,thelongitudinalgradientandcrosssectionslopearefrom0.0348to0.0775andfrom0.0115to0.038,respectively.Differentmodelmaterialswithamediumdiameterof0.021mm,0.076mmand0.066mmcoverthreeexperimentseach.Anartificialrainfallequipmentisasprinkler-systemcomposedof7downwardnozzles,distributedbyhexagontypeandagivenrainfallintensityis35.56mm/hr.cm2.Threeexperimentsaredesignedbyprocess-responseprincipleatthebeginningtheψshapedsmallnetworkisdugintheflume.Runningtimespansare720m,1440minutesand540minutesforRunsⅠ,ⅣandⅥ,respectively.Threeexperimentsshowthatthesedimentyieldprocessesarecharacterizedbydelayingwithavibration.Duringnetworkdevelopmenttheenergyofadrainagesystemisdissipatedbytwoways,ofwhichoneisincreasingthenumberofchannels(rillandgully),andtheotheroneisenlargingthechannellength.Thefractaldimensionofadrainagenetworkisexactlyanindexofenergydissipationofadrainagemorphologicalsystem.Changeofthisindexwithtimeisanunsymmetricalconcavecurve.Comparisonofthreeexperimentsexplainsthatthevibrationandthedelayingratioofsedimentyieldprocessesincreasewithmaterialcoarsening,whilethenumberofchanneldecreases.Thelengthofchannelenlargeswithmaterialfining.Thereexistsnon-linearrelationshipbetweenfractaldimensionandsedimentyieldwithanunsymmetricalhyperboliccurve.Thebsolutevalueofdelayingratioofthecurvereduceswithtimeunningandmaterialfining.Itischaracterizedbysubstitutionofsituationtotime.