③首都公园协会成立于1882年，首任主席是布拉巴宗勋爵，其宗旨是为公众使用而保护花园、废弃墓地、教堂、开敞空间等，参见该协会网站：http://www.mpga.org.uk/。
    ④指植物所具有的抵抗不利环境的某些性状，如抗寒、抗旱、抗盐、抗病虫害等。
    ⑤相关研究参见Henry W.Lawrence,"The Greening of the Squares of London:Transformation of Urban Landscapes and Ideals",Annals of the Association of American Geographers,Vol.83,No.1,1993,pp.90-118; Henry W.Lawrence,City Trees:A Historical Geography from the Renaissance through the Nineteenth Century,Virginia:University of Virginia,2006,p.77.
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