Abstract: Residential area’s vegetation will become an important component of C hina’s urban vegetation, and the distribution pattern of its diversity will aff ect urban vegetation diversity. Based on the residential area’s vegetation inve stigation in the urban, suburban, and rural areas of Shanghai, the plant diversi ty and species composition in the residential areas along the urban-rural gradi e nt were compared in terms of ornamental plants (OP), spontaneously occurring orn amental plants (SOOP), and weeds. There was no significant difference in the spe cies richness of OP and weeds along the gradient, but the richness of SOOP was t he highest in suburban area. The species compositions of OP, SOOP, and weeds wer e similar in the residential areas along the gradient, with 40〖KG-*2〗-〖KG-*7 〗50% of all species occurring in more than one location. The main causes induci ng the homogenization of plant diversity in Shanghai residential areas were the almost identical residential building styles and greening patterns, which limite d the planting of greening plants and the construction of heterogeneous habitats .

Key words: Dianchi Lake, wetland plant, degraded wetland, plant community, species invasion.