Heterogeneity and pattern of tree in Shenzhen special economic zone's urban forest, China

The adverse impacts of urbanization on urban sustainable development and biodiversity have attracted attention. The study aims to fully understand the associations between the composition, structure and diversity of green space and functional type of urban land. The result shows that (1) the urban forest is composed of 337 species in 203 genus of 78 families. CUFT has the highest species richness, but Acacia mangium and Eucalyptus citriodora have covered a relatively high proportion as exotic species, especially Eucalyptus citridora, is overwhelmingly dominant in CUFT than that in other urban forest type. The phenomenon, rarely seen in the similar study of other cities and the long-history forests, reflects that the natural forest and native species have suffered serious damage in the primary phase of the Shenzhen SEZ's development. (2) RSFT has the highest exotic species, followed by ROFT, INFT, REFT and CPFT. The result reflected human-controlled characteristic. Exotic species, mainly originating from tropical Asia, Australia and tropical America, vary widely amongst different land functional types. Acacia mangium is the dominant species in CUFT, REFT and ROFT. (3) Evergreen broadleaf species are prominent, whereas palms also play a very important role. Native species, mainly remnant spontaneous growths, mostly exist in CUFT.