Abstract: Urban green spaces are important for maintaining urban biodiversity. From April 2022 to January 2024, we employed the transect method to investigate bird communities in two representative urban green spaces of Nanjing City, Laoshan National Forest Park located in the suburbs and Zijinshan National Forest Park situated in the city center. A total of 117 bird species and 7833 individuals were recorded, with 103 species (3987 individuals) being observed in Laoshan and 89 species (3846 individuals) in Zijinshan. We quantified species diversity and functional diversity of birds in both parks using the Shannon index, Simpson index, Pielou’s evenness index, Rao’s quadratic entropy, functional evenness, and functional divergence. We analyzed the differences in bird community composition at the functional group level across different seasons between the two parks. Results showed significant differences in species diversity and functional diversity between the two parks. Overall, Laoshan exhibited higher bird diversity during summer, whereas Zijinshan showed greater diversity in autumn and winter. Species composition differed significantly between the two parks, with the highest BrayCurtis dissimilarity in spring. In spring, the proportion of functional groups nesting in shrubs, cliffs, or walls, and those foraging on water surfaces, was significantly higher in Zijinshan. These findings demonstrate that the configuration of urban green spaces has a profound impact on bird communities. We recommend enhancing the effectiveness of urban biodiversity conservation through rational planning of urban green spaces, such as increasing habitat types suitable for various bird species.

Key words: suburban area, urban center, bird diversity index, community structure, seasonal difference