[Homogenization of plant diversity in Shanghai residential areas]

Residential area' s vegetation will become an important component of China's urban vegetation, and the distribution pattern of its diversity will affect urban vegetation diversity. Based on the residential area's vegetation investigation in the urban, suburban, and rural areas of Shanghai, the plant diversity and species composition in the residential areas along the urban-rural gradient were compared in terms of ornamental plants (OP), spontaneously occurring ornamental plants (SOOP), and weeds. There was no significant difference in the species richness of OP and weeds along the gradient, but the richness of SOOP was the highest in suburban area. The species compositions of OP, SOOP, and weeds were similar in the residential areas along the gradient, with 40-50% of all species occurring in more than one location. The main causes inducing the homogenization of plant diversity in Shanghai residential areas were the almost identical residential building styles and greening patterns, which limited the planting of greening plants and the construction of heterogeneous habitats.