Cross-Scale Mapping of Blue-Green Infrastructure: A Case Study of the Guangdong-Hong Kong-Macao Greater Bay Area

The deepening understanding of coupled human and natural systems demands a rethink in the concept and construction methods of blue-green infrastructure (BGI) during spatial development and governance. Aiming to understand and identify the development and change of the coupling relationship among multi-scale blue-green systems, this research introduces a cross-scale mapping method for territorial spatial planning and design. From the perspective of complex adaptive systems, it analyzes and compares the spatial relationship between landscape substratum, infrastructure networks, and human settlements with multiple-scale spatial data and morpho-typological knowledge. Taking the Guangdong-Hong Kong-Macao Greater Bay Area as an example, the research adopts the aforesaid cross-scale mapping method to identify and present the BGI development process, and accordingly reveal the development laws of BGI in such aspects as composition, pattern, and scale in different periods. On this basis, the research argues that the study of the development laws, especially those in the representation and continuation of the historical pattern and scale, allows a more resilient BGI with richer connotations to continue and improve the stable state of the territory, despite the dramatic changes in both the scale and pattern of spatial development and governance.