Mechanisms Driving Ground-Dwelling Animal Diversity Responses to Urbanization Gradients: A Case Study From the Chuhe River Riparian Zone in Nanjing, China.

Urbanization is a major driver of global ecosystem change and biodiversity loss. Ground-dwelling animals, due to their reliance on near-ground resources and sensitivity to human disturbance, serve as important indicator taxa in urban ecosystems. Understanding the responses of ground-dwelling animals to urbanization is therefore critical for the design and management of urban green spaces. In this study, we evaluated the responses of ground-dwelling animal communities to urbanization along the Chuhe River riparian zone in Nanjing, China. Using camera trap data and a set of urbanization-related variables, we examined community patterns across taxonomic, functional, and phylogenetic dimensions of diversity. The results showed that: (1) no significant differences in α diversity were detected among urban, suburban, and rural sites; (2) generalized linear models indicated that different urbanization-related factors exerted significant and taxon-specific effects on diversity metrics, with building height, building density, road density, and distance to the government site being key variables; and (3) RLQ analysis revealed significant associations between urbanization and functional traits, with more urbanized areas favoring species characterized by larger body size, carnivorous diets, ground-dwelling habits, and solitary behavior. Overall, urbanization did not lead to significant changes in local diversity across categorical urbanization gradients, but influenced ground-dwelling animal communities through specific urbanization-related factors and trait-based filtering processes. These findings highlight the importance of integrating multiple diversity dimensions and trait-based perspectives into urban ecological research and planning.