外文翻译-城市的流动性和城市形态：不同模式的城市扩张产生的社会和环境成本

毕业设计外文资料翻译题目城市流动性和城市形态：不同模式的城市扩张产生的社会和环境成本学院土木建筑学院专业建筑学班级学生学号指导教师二〇一一年三月二十八日EcologicalEconomics40(2002)199–216Urbanmobilityandurbanform:thesocialandenvironmentalcostsofdifferentpatternsofurbanexpansionRobertoCamagni,MariaCristinaGibelli,PaoloRigamontiAbstract：Thequestionoftheenvironmentalorsocialcostsofurbanformisincreasinglyattractingattentioninspatialpolicy,butscientificdebateinthisfieldisoftenmarredbyprejudicesandabstractvisions;empiricalanalysesareveryrare.Thepresentstudyaimsatestablishing,inthemetropolitanareaofMilan,whetherdifferentpatternsofurbanexpansioncouldbeassociatedwithspecificenvironmentalcosts—inparticular,forlandconsumptionandmobilitygeneration.Differenttypologiesofurbanexpansionweredefined,andanimpactindexweightingdifferentlyjourney-to-worktripswithreferencetomodeandtimelengthwasbuiltatthemunicipalitylevel.Thestatisticalanalysisconfirmedtheexpected‘‘wasteful’’characterofsprawlingdevelopmentpatternsintermsoflandconsumption,thoughsuggestingthatrecenturbandevelopmentisbecomingrelatively‘virtuous’withrespecttothepast.Withreferencetothemobilitygenerated,higherenvironmentalimpactswereprovedtobeassociatedwithlowdensities,sprawlingdevelopment,morerecenturbanisationprocessesandresidentialspecialisationofthesinglemunicipalities.Publictransportseemstobestronglyinfluenced,bothintermsofefficiencyandcompetitiveness,bythestructuralorganisationofanurbanarea:themoredispersedandlessstructuredthedevelopment,theloweritslevelofefficiencyandcompetitivenessandconsequentlyitsshareofthemobilitymarket.Onthecontrary,triptimesforprivatetransportappeartobecorrelatednotsomuchtourbandimensionordensityastothepresenceofrecenthousingdevelopment,indicatingtheemergenceofnewmodelsoflifestyleandmobilitywhichareverydifferentfromthoseofthepast.©2002ElsevierScienceB.V.Allrightsreserved.Keywords:Urbanexpansion;Urbanform;Urbansustainability;Publictransport1.IntroductionTogetherwithtechnologiesandconsumptionstyles,theformofsettlementsandthewayhumanactivitiesareorganisedingeographicalspacerepresentcrucialresearchfields—andsourcesofpreoccupation—asfarasecologicalequilibriaareconcerned(Camagnietal.,1998).Infact,inprinciple,theresource-efficiencyofdifferentsettlementpatternsissubjecttowidevariationswithreference,atleast,totwoscarcenaturalresources:landresources(forresidentialuses)andenergyresources(formobilityuses).Landconsumptiondependsdirectlyontherelativecompactnessofhumansettlementsandonresidentialdensity;energyconsumption,ontheotherhand,dependsindirectlyonthesamevariables,viatheirlinkagewithmobilitypatterns:triplengthandmodalchoicebetweenprivateandpublicmeans.Thestudyisdividedintotwomainparts.Inthefirstpartweanalysethetypicalfeaturesofcurrenturbandevelopmentandlookattheresultsofsomerecentinternationalempiricalanalysesonthecomparativecostsofdifferenttypologiesofurbandevelopment(Section2);inthesecondpartwepresentthemainfindingsofourempiricalanalysescarriedoutintheprovinceofMilan:wedefineanumberofarchetypalformsofurbandevelopment(Section3.1),measuretheassociatedconsumptionofland(Section3.2)andthencarryoutadetailedanalysisofthemobilitygeneratedanditsenvironmentalcosts(Section3.3).2.Developmentattheurbanfringe:dynamics,interpretationsandempiricalanalysis2.1.Emergingurbanformanditsrele
anceforsustainablede
elopementInEurope,theareassurroundingmostlargecitieshavebeenradicallytransformedoverthelast20years.Notonlyhastherebeenanincreaseingamountofbuiltdevelopment,butthishasspreadextensivelyinformswhichareverydifferentfromthosecharacterisingtraditionalsuburbanisation,i.e.expansionthatoccurredaroundadenseurbannucleus,prevalentlythroughextensionand/orrelativelycompactdevelopment.Manyurbanareas,althoughdemographicallystatic,oratthemostshowingweaksignsofpopulationgrowth,havespreadoutand‘diluted’overspaceinaformofdevelopmentwhosefeatureshavebeenveryeffectivelydescribedwiththetermsprawl:lowdensitydevelopment,extendingtotheextremeedgeofthemetropolitanregionandlocatedinarandom,‘leapfrog’fashion,segregatedinspecialisedmono-functionallanduses,andlargelydependentonthecar(Mayetal.,1998;OECD,2000).Therearemanycloselyinterrelatedreasonsforthesuccessofthe‘diffusedmetropolis’.Asfarasresidentiallocationisconcerned,themainreasonsappeartobe:thedeclineinenvironmentalqualityofthedenselybuiltcitycentre,duetotrafficcongestion,pollution,degradationofpublicspacesandreductionofsafety;changeinlifestyles,dueinparttotheincreaseinincomes,infavourofmorespaciousdecentralisedhousing;thereplacementofresidentiallanduseinthecitycentrebytertiaryactivities;thefactthathousingimprovementinthecitycentrecostsmorethannewconstructionoutsidethecity;andthehousingsupplystrategiesofrealestateagents,whichfindlessresistanceinthemorespaciousout-of-townareas.Thosewhotakethesecondapproachmaintainthatitiscrucialtointervene,throughtheadoptionofsectoralandspatialplanningpolicies,tocontainurbansprawl.Theyconsiderthecurrent,andaboveall,theprobablefuturecostsundesirable,maintainingthatthesearelikelytogrowexponentiallyintheabsenceofcorrectivemeasures.Theemergenceofthethemeofurbansustainabilityisanelementwhich,inrecentyears,hasstrengthenedthissecondview,stimulatingavarietyofreflectionsandalsooperativeindications.ThefirstapproachiswellrepresentedintheEuropeancontextbythe‘theoreticians’ofthevillee´mergente(ChalasandDubois-Taine,1997),convincedopponentsofanylargescaleplanningaimedatcontrollingurbansprawlorrestrictingthemobilityandlocationpreferencesofindividualsoreconomicactivities.Theyarguethatitisimpossible(duetothegrowingcomplexityofthespatialinteractionspermittedbycarmobility),pointless(asnewtechnologieswillallowincreasingfreedomoflocation),butaboveallsociallyundesirablesincethe‘villea`lacarte’,orthe‘villeauxchoix’willofferanincreasingfreedomforpeopletodesigntheirown‘life-spaces’andinterpersonalrelations,aprocessinwhichitisnotacceptabletointerfere.EvenmoreradicalistheviewoftheNorthAmericanfree-marketeers,whoclaimthattheproblemscausedbyextensivesuburbanisationareoverestimated,emphasisingthatthenewinformationtechnologiesaresettoacceleratethedispersionofpopulationandjobsuntilphysicalproximitywillbecomeirrelevant.Theyargue(GordonandRichardson,1997):·thatonlyunacceptablepoliciesof‘commandandcontrol’couldconsiderinterferingwiththeevidentindividualpreferenceforlowdensityhousing;·thattherelationshipbetweenurbandensificationandreductionofenergyconsumptionisnotscientificallyproved;·thatspontaneousprocessesofself-correctionarepossibleintheshorttomediumtermtoreducethehome-to-workdistance,asshownbytheedge-cityphenomenon;·thattheefficiencyofmorecompactsuburbandevelopmenthasyettobedemonstrated,bothintermsofcostsandsocialre-equilibrium;·andfinallythattop-down,largescaleplanningwouldrisktakingawayresponsibilityfromlocalauthoritiesinaperiodofglobalisationandgrowingcompetitionbetweencitiesinwhichanyplanningerrorisimmediatelypunishedbythemarket.Thismetaphorhasbeenputinquestionbysomescholarsastoobroad,genericandideological(Breheny,1992;Banister,1992;Jenksetal.,1996).Inparticular,theurbanscaletowhichitshouldapplyremainsuncertainand,beyondcertainlevelsofdensityandsize,itcouldproduce‘towncramming’andscalediseconomieswhichareamongthemaincausesofpresentsuburbanisationtendencies(Elkinetal.,1991;Fouchier,1998).Asufficientagreementexists,though,aboutthedesirabilityofapolycentricurbanstructure,organisedonsmallandmedium-sized,compactcentres,wellconnectedthroughanefficientnetworkofpublictransport(BrehenyandRookwood,1993;Blowers,1993;Breheny,1996;HallandLandry,1997),wesometimescalleda‘wiselycompact’urbanstructure(CamagniandGibelli,1996).2.2.DemandformobilityanditsrelationshipwiththeformofcityexpansionThedemandformobility,andinparticularthegrowingdependenceonprivatevehiclesforintra-metropolitantrips,iscurrentlyacrucialcomponentinthedebateonsustainableurbandevelopment,giventheeconomic,socialandenvironmentalimpactforwhichitisresponsible.Adiffusedpatternofurbandevelopment,almostbydefinition,cannotbeadequatelyservedbythepublictransportinfrastructuresincethedemanddensityislow,thescatteringofthedemandovertheterritoryishighandthedispersionofdestinationsisalsogrowingbecauseofthesuburbanisationofjobs.Thisisthereasonwhysomanyanalysesofthesocial,economicandenvironmentalcostsofurbanexpansionhaveconcentratedonthepervasivepresenceoftheautomobile:atechnologycapableof‘bringingplacesnearer’byprovidingaccesstotheincreasinglydispersedandspecialisedurbanfunctions(Cervero,1998;NewmanandKenworthy,1999).ThesubjecthasalreadybeenwidelyinvestigatedinNorthAmerica,andisnowbecomingthefocusofdebateinEurope,too,giventheemergenceofthephenomenonofsprawlingurbandevelopmentanditsincompatibilitywiththeobjectivesofsustainability.Onequestionposedbymanyresearchers,andalsoexaminedinthepresentinvestigation,iswhetheritispossibletodemonstrateasignificantrelationshipbetweenmobilityconsumptionandthemorphologyofurbandevelopment.Inthisconnection,itisinterestingthatanempiricalanalysisundertakenrecentlyintheParismetropolitanareashowsadirectrelationshipbetweentherateofcarownershipanddistanceoftheareaofresidencefromthecentre,andalsoanindirectrelationshipbetweenthedemographicdensityoftheareaofresidenceandvariablessuchastherateofcarownership,thedistancetravelledeachdayandthepercapitaconsumptionofpetrol(Fouchier,1998).2.3.Thecostsofsprawlininternationalsurveys:landconsumptionandpubliccostsWenowcometothecentralthemeofourresearchprogrammeonthecommunitycostsofsuburbandevelopment,inordertounderlineimmediatelyadifficultythatouranalysisshareswithotherinvestigationsattheinternationallevel.Althoughgoodevidencehasalreadybeenprovidedoftheeconomic,socialandenvironmentalcosts,findingsrelatingtothepubliccostsofsprawlaremodest,duemainlytotheobjectivedifficultiesoffindingsignificantandreliableperformanceindicators.ThespecificresultsavailablerelatetostudiescarriedoutpredominantlyinNorthAmericaandthereforerefertoratherdifferentsuburbanisationpatternsandaverydifferentinstitutional/administrativecontext.Nevertheless,itissignificantthatthefindingsrevealasignificantcorrelationbetweendifferentformsofurbangrowthandpubliccosts.Pioneerresearchwascarriedoutinthisfieldin1974bytheRealEstateResearchCorporationoftheUSGovernmentinordertoestimatetheeconomicandenvironmentalcostsofdifferenttypesofurbandevelopmentanddifferentformsofgrowthontheurbanfringe.Theempiricalanalysesconsiderthepubliccostsrelatingtotheconstructionandmaintenanceofschools,housing,greenspace,roadsandshoppingcentres,andestimatethecoststothecommunityintermsofthenegativeenvironmentaleffects(landconsumption,air,waterandnoisepollution)andsocialeffects(carjourneytime,accidents,psychologicalandsocialcosts).Themainresultofthisresearchwastheidentificationofurbandensityasthefundamentalvariableoftheoverallcostssustainedbythecommunity(RealEstateResearchCorporation,1974),thoughtheseconclusionsdidnotgounchallenged:see,amongothers,Altshuler(1977)andWindsor(1979).Thisresearch,whichmadeuseofstatisticalanalyses,casestudiesandsurveysoflocalauthorities,examinesfivetypesofdevelopment:thedensificationofthecitythroughre-useandinfill,urbanextension,keyvillageextension,multiplevillageextension,andnewsettlement.Theadvantagesanddisadvantagesofeachtypewereassessedintermsoftheeconomic,socialandenvironmentalcosts,bothpublicandprivate,withtheaimofformulatingrecommendationsandsuggestionsforactionaimedatvariousadministrativelevelswithresponsibilityfortownandcountryplanning.Theauthorsthemselvesdeclarethefindingstobelargelyinconclusiveastothepreferablemodel.3.Socialcostsofdifferenttypologiesofurbanexpansion:landconsumptionandmobilitypatterns3.1.TypologiesofurbanexpansionFollowingthegeneralreflectionsoutlinedabove,thepurposeofourempiricalanalysis,carriedoutintheprovinceofMilano,wastoidentifythecharacteristicsofurbandevelopmentandthesocialcostsoftheurbanexpansionwhichoccurredduringtheten-yearperiod1981–91.ThevariablesexaminedincludetheconsumptionoflandforhousingdevelopmentandUsingasastartingpointthemapsdrawnupbyCentroStudiPIMonlandconsumptionintheMilanoareain1991,thepatternsofresidentialdevelopmentovertheperiod1981–91ineachofthe186communeswithintheprovincewereanalysedusingadescriptive/intuitiveapproach.Atthemacrolevel,itwaspossibletodistinguishfivetypesofurbanexpansion:·infilling(T1),·extension(T2),·lineardevelopment(T3),·sprawl(T4),and·large-scaleprojects(T5).TypeT1ischaracterisedbysituationsinwhichthebuildinggrowthoccursthroughtheinfillingoffreespacesremainingwithintheexistingurbanarea;T2occursintheimmediatelyadjacenturbanfringe;T3isdevelopmentwhichfollowsthemainaxesofthemetropolitantransportinfrastructure;T4characterisesthenewscattereddevelopmentlots;T5concernsnewlotsofconsiderablesizeandindependentoftheexistingbuiltupurbanarea.Allthecombinationsamongthesetypeswerethenidentifiedand,finally,byeliminatingandre-assigningtheleastsignificantcombinations,aselectionof10prevalenttypologieswasarrivedat.Thesetypologieswereusedinthestatisticalanalysisonlandconsumption;inthesubsequenteconometricanalysistheywerereducedtofourmaintypologiesandusedasindependentdummyvariables,togetherwithothervariablesreferringtosettlementstructure,intheinterpretationoftheenvironmentalimpactofmobility.Beforegoinganyfurther,weshouldspecifyanimportantcaveat.Giventhelevelofsubjectivityinherentintheattributionofthevariouscommunestothedifferentcategories,theresultswhichwenowanalysemustbetakenasapreliminaryapproximation.3.2.Asfarastheanalysisoflandconsumptionisconcerned,thefirstsurveywecarriedoutcomparesthelandareadevelopedforresidentialandserviceusebetween1981and1991ineachcommunetothenumberofdwellings.Thisindicatorwaspreferredtothepercapitaconsumptionoflandbecausethelattermayincreaseincaseswherethepopulationofacommunedeclines,givingafalseindication.Threemaincategoriesemerged(Fig.1):·therelatively‘thrifty’types,whereconsumptionwasbelow450m2perdwelling,whichcorrespondedasexpectedtothecategories‘pureinfilling’and‘largescaleprojects’;·therelatively‘land-greedy’types,whichbelonged,againasexpected,tothecategories‘puresprawl’,‘lineardevelopment-sprawl’,and‘extension-sprawl’,whereconsumptionwasabove600m2perdwelling,plus‘extension-linear’developmentwith
550m2perdwelling;·anintermediategroup,whichincludedthecategories:infilling-extension,infilling-sprawl,pureextensionandpurelineardevelopment,withconsumptionaround500m2perdwelling.Ifweobservetheratiobetweenthenewbuiltupareaandnewdwellingsintime(1981vs.1991),anunexpectedlypositivetrendemerges.Infact,foralltypesofdevelopment(exceptinfilling),theconsumptionoflandperdwellingisslightlydecliningintime.Thissuggeststhatnewurbandevelopmentoverallisrelativelyland-sparingcomparedwiththepast.3.3.Thedemandformobilityanditssocialcosts3.3.1.MethodologyItemergesclearlyfromtheliteraturethatthedemandformobilityisanimportantcomponentoftheenvironmentalimpactofurbandevelopment,asillustratedinSection2.Forthisreason,inthepresentstudyitwasdecidedtoestablishwhetheritispossibletoidentifysignificantdifferencesofbehaviourwithinthestudyareaasfarasmobilitywasconcernedand,ifso,toascertainwhetherthereisanysignificantcorrelationbetweenthesedifferencesandvariablesdescribingtheformofdevelopment.Theintentionistoprovideabasisfororientingplanningpolicies.Theworkinghypothesisisthatwithinarelativelyhomogeneousarea(intermsofincomelevelandgeneralsocio-economicconditions),suchastheprovinceofMilano,thelocaldifferencesinthemobilitypatterns(timeandmode)can,atleasttoacertainextent,beattributedtotheforminwhichurbangrowthhasoccurred.Mobilitythereforehastheroleofdependentvariable,whiletheformofdevelopmentanditsdynamicsrepresenttheindependentvariables.Fourtypesofindependentvariableswereadopted(seeAppendixAforstatisticaldetailsanddefinitionofvariables):·geographicalvariables:distancefromMilan;·socio-economicvariables:populationdensity,sizeanddynamics,ageofbuildings,ratioofjobstoresidentpopulation(Emp/Res);·morphology:i.e.thetypologiesofurbandevelopmentpreviouslydescribed,reducedtofourclasses:infilling-extension;extension-linear;sprawl;large-scaleprojects(seeAppendixA);·accessibilityandtransportefficiency:competitivenessofpublictransport,shareofpublictransport,averagetriptimeforpublictransporttrips(Publictime)andprivatetransporttrips(Privatetime).3.3.2.FactorsdeterminingtheintensityofthemobilityimpactThespatialdistributionoftheindicesofimpactintensitywasexaminedusinganeconometricanalysistoascertainwhethertherewasasignificantcorrelationwithanyoftheselectedindependentvariablesdescribingthecharacteristicsoftheurbanform..ItisimportanttonoteherethatusingthesetechniquesinsteadofOLSdidnotinvolve,forourmodelandforouraims,bigdifferencesintheresults(Table2).Therefore,itispossibletosaythattheinferencebasedonthesimplerOLSestimators,whilenotcompletelyaccurate(aboveallasfarasthestandarddeviationoftheestimatorsisconcerned),isnotmisleading.Forthisreason,intheremainderofthepaperonlyOLSestimatorswillbedisplayed,eventhoughweacknowledgethatmoreefficientestimatorscouldbefound,inparticularifwewereinterestedintestinghypothesesaboutthevalueoftheparameters.Theoutcomeissummarisedbrieflyasfollows:·asignificantinverserelationshipwasfoundbetweentheindexmeasuringthemobilityimpactandnetpopulationdensity(densityofthebuiltuparea),inlinewiththeexpectationsexpressedintheinternationalliterature.Togetherwiththesizeoftheurbanareasintermsofabsolutepopulation,densityappearstohavemainlyanindirecteffectonthemobilityimpact,throughitsinfluenceontheaveragetriptimeofpublictransportandhenceonthemodalsplitofcommutertripsinfavourofpublictransport;·asignificantrelationshipalsoexistswiththevariablesrepresentingdemographicgrowthrateandtheaverageageofhousing.Inbothcases,theimpactindexincreasedwiththedynamismofthecommunesconcerned:inotherwords,highvalueswereassociatedwithcommuneswitharapidgrowthofpopulationoverthetenyearperiod1981–1991andalsothosewithnewerhousing,i.e.areasofrecentexpansion;·thecoefficientrelatingtothedistancefromthecentreofMilanissmallintermsofabsolutevalues(0.006pointsperkm),butissignificantlylessthanzero,indicatingthegreaterautonomyofthetownsinthemostexternalpartsoftheprovinceandaspatialstructureofsettlementssimilartothatofaself-contained‘industrialdistrict’;·followingthesubdivisionintogroupsproposedinthepreviousparagraph,threedummyvariableswereintroducedtoallowforinterceptshift.Theanalysisoftherelativecoefficientsmakesitpossibletoestablishthefollowingranking(inincreasingorderofimpact):infillextension,extension-lineardevelopment,sprawl,large-scaleprojects;·finally,ananalysiswasmadeoftheroleoftheemployment/residentsratio,avariabletowhichtheliteratureattributesconsiderableimportanceinconnectionwithmobilitydemand.Thisrelationshipcanbeconsideredanindicatoroftheleveloffunctionaldiversification–integration–segregation,the‘functionalmix’ofeachcommune.Asignificantandnegativerelationshipemergedinthemultipleregressionanalysis,indicatingthatthemobilityimpactwashigherwhentheproportionofemploymentwaslower,i.e.inareasofspecializedresidentialnature.3.3.3.Componentsofthemobilityimpact:modalchoiceandtriptimeAswehaveseeninSection3.1andTable1,themobilityimpactindexistheresultoftwocomponents:transportmodeandtriptime.Thesetwocomponentsdeterminetwodistinct‘logicalchains’throughwhichitispossibletohypothesiseacausalrelationshipbetweenthephysicalstructureofurbandevelopmentandthesocialcostsrepresentedbythemobilityimpact(Fig.2).Ontheonehand,wehave:·settlementsofrelativelycompactstructure→greatercompetitivenessofpublictransport(intermsofjourneytoworktime)→greateruseofpublictransport→lowermobilityimpact(lefthandlogicalchaininFig.2);ontheother:·settlementsofrelativelycompactstructure→greaterefficiencyofbothpublicandprivatetransport→lowercommutingtime→lowermobilityimpact(right-handlogicalchaininFig.2).Beforemovingtowardstheeconometricanalysis,itseemsnecessarytomakeamethodologicalpoint.Acausalinterpretationofthemodelspresentedinthefollowingcannotbederivedfromastatisticalestimationprocess,butcanbemaintainedonlyonthebasisofaprioritheoriesorknowledgeregardingthephenomenonunderconsideration.Itthenfollowsthatalltheestimatesreportedbelowcangiveonlyanideaofthestrengthofthecausalconnectionsbetweentheinvolvedvariablesandnotoftheirdirection.4.ConclusionsThewidedispersionofmetropolitanpopulationandthespreadofsettlementpatternswithahighconsumptionofscarceornon-renewableresources(especiallylandandenergy)arerelativelyrecentphenomenainEurope.Theyhavetriggereddebate,innewformsandwithnewpolicyoptions,ofanissuealreadywellrootedinthetownplanningtradition,thatofurbancontainment.Neologismssuchas‘villee´clate´e´’,‘villee´mergente’,‘citta`diffusa’,‘ubiquitouscity’andsoon,haveallbeenusedtoexpressthisrenewedinterest,thoughrepresentingdifferentanalyticalapproachesandinterpretations.Itwasinthiscontextthatthepresentempiricalanalysiswasdeveloped,withtheaimofestablishing,inthemetropolitanareaofMilan,whetherdifferentpatternsofurbanexpansioncouldbeassociatedwithdifferentsocialandenvironmentalcosts—inparticular,forlandconsumption,and,aboveall,mobilitygeneration.Asfaraslandconsumptionisconcerned,threemaincategoriesemerged:acategoryofrelatively‘virtuous’patterns(pureinfillandlarge-scaleprojects),anintermediatecategory(infill-extension,infill-sprawl,pureextensionandpurelineardevelopment),andfinallya‘wasteful’categoryofdevelopment(encompassingpuresprawl,lineardevelopment-sprawl,extension-sprawl,andextension-lineardevelopment).Thiswasinlinewithexpectations.Ananalysisofthedynamicaspects,however,revealedanunexpectedtrend:overtheperiod1981–91theconsumptionoflandperdwellingdecreasedslightlyforalldevelopmenttypes,suggestingthatrecenturbandevelopmentisbecomingrelatively‘virtuous’withrespecttothepast.Secondly,withreferencetothequestionofmobility,anindexofenvironmentalimpactofthemobilitygeneratedineachmunicipalitywasbuilt,weightingdifferentlythedifferentmodesandtimelengths.Urbandensity,demographicgrowthrates,ageofthebuildingstockandfunctionalmix(economic-residentialbalance)wereprovedtobestatisticallysignificantinexplainingmobilityimpact.Higherimpactsareassociatedwithdiffused,sprawlingdevelopment,morerecenturbanisationprocessesandresidentialspecialisationofthesinglemunicipalities.Publictransportseemstobestronglyinfluenced,bothintermsofefficiencyandcompetitiveness,bythestructuralorganisationofanurbanarea:themoredispersedandlessstructuredthedevelopment,theloweritslevelofefficiencyandcompetitivenessand,consequently,itsshareofthemobilitymarket.Onthecontrary,triptimesforprivatetransportappeartobecorrelatednotsomuchtourbandimensionordensityastothepresenceofrecenthousingdevelopment,indicatingtheemergenceofnewmodelsoflifestyleandmobilitywhichareverydifferentfromthoseofthepast.Intermsofmobility,theleastenvironmentallyacceptablesituationsarerepresentedbytwooppositetypesofdevelopment(sprawland‘large-scaleprojects’),whichshowaverydifferentbehaviourwithrespecttothemodalsplit.Sprawlisassociatedwiththelowestshareofpublictransport,whilelargeprojectshavethelowestshareoftripsmadeonfoot.Inconclusion,ourresultsconfirmthefarsightednessofthestrategicguidancesandinnovationsattheurbandesignlevelthataimtowardsa‘wiselycompact’andpolycentricpatternofurbandevelopment.ReferencesAltshuler,A.,1977.ReviewoftheCostsofSprawl,JAIP43,April,207–209.Blowers,A.(Ed.),1993.PlanningforaSustainableEnvironment.AReportbytheTCPA.Earthscan