关键词: 香港, 广州, 城市树木, 行道树群落, 城市生态

Abstract: As the major cities of the south China, Hong Kong and Guangzhou have nearly with simi-lar geographical and physical conditions. However, there are significant differences in the char-acteristics and composition of their magnitude of domination have their respective unique fea-tures. As a cosmopolitan city, Hong Kong has introduced more tree species and resulted in a roadside tree stock of richer species diversity and higher percentage of exotic composition than those of Guangzhou. With a different urban history and resulting city morphology , the aver-age density of roadside trees in Hong Kong is less than that in Guangzhou. Comparing with Guangzhou, Hong Kong’ s roadside trees are dominated by species with small final-dimen-sions. The confined and high-density habitats in Hong Kong have limited more significantly the formation and growth of its roadside trees than those in Guangzhou.

Key words: Key words Hong Kong, Guangzhou, urban trees, roadside-tree communities, urban ecology