What are the key and catalytic external factors affecting the vitality of urban blue-green space? a case study of Nanjing Main Districts, China

In recent years, urban blue-green space has received increasing attention as an important carrier of urban spatial vitality. It has become increasingly clear that urban blue-green spaces both cities and citizens, though these concepts of spatial vitality and the underlying mechanisms influencing spatial vitality have yet to be explored in depth. Using blue-green spaces in the Nanjing Main Districts as an example, this study employs precise Location Based Services (LBS) data as a proxy for spatial vitality to explore the influence of external factors and their interaction(s) on spatial vitality. The results demonstrate that (1) functional mixing and walking accessibility are the dominant external factors affecting blue-green spatial vitality; (2) the interaction of external factors has a significant impact on spatial vitality, and finally (3), that public transportation accessibility and regional economic conditions are the catalytic factors affecting spatial vitality, explaining the contradictory research results discovered by other scholars. This study provides a foundation for the planning and construction of urban bluegreen spaces.