美国绿道理论研究

jackahern3

GreenwaysintheUSA:theory,

trendsandprospects

3.1Introduction

DevelopmentinEuropeandtheUSAhavecommonroots,buttoagreatextenttheywenttheirownwayowingtogeographical,politicalandscienti cdifferences.WhereasecologicalnetworksarecommoninEurope,greenwaysaremuchmoreanAmericanproduct.

Thischapterisorganisedtoaddressseveralobjectives:

rrtocompareclassicandemergingde nitionsofgreenways

toarticulategreenwaytheory,andtolinkde nitionswiththeoreticalrprinciples

rtoreviewtheoriginandevolutionofgreenwaysintheUSA

todiscussfutureprospectsandresearchneedsforgreenways

Greenwaysisa‘new’wordwithmanymeanings.Muchconfusionstillexistsarounditsde nition,yetitcontinuestogaininpopularityandtoappearregu-larlyinpopularlanguageandplanningpolicyintheUSAandinternationally(FabosandAhern1995).Themanydifferingperspectivesongreenwaysarere- ectedinthesede nitionsandservetoemphasisethecomplexityofthegreen-wayconcept.Abriefreviewofthesede nitionsprovidesausefulintroductiontothesubjectofgreenways,andunderscorestheneedforacommonde nitionandtaxonomy,tosupportinternational,interdisciplinarycommunicationandcollaboration.

Perhapsthemostwidelyacceptedcontemporaryde nitionorstatementongreenwaysintheUSAwasincludedinthereportofthePresident’sCommis-siononAmericansOutdoorsintheUSA(1987).TheCommissionadvocatedagreenwaysnetwork:

toprovidepeoplewithaccesstoopenspacesclosetowheretheylive,

andtolinktogethertheruralandurbanspacesintheAmerican

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