Identification of green infrastructure networks based on ecosystem services in a rapidly urbanizing area

Urban growth accompanied by sharp environmental changes has degraded ecosystem services (ESs). Green infrastructure (GI) is premised on the various social and ecological benefits of high-quality ESs that humans acquire from natural ecosystems; hence, the conservation of GI can be considered an effective way to safeguard ecological security and contain rapid urban sprawl and outward expansion. Taking Hangzhou, a typical ecologically sensitive but rapidly urbanizing area, as the case study, a GI network was established according to the quantification and mapping of diverse ES values. The equivalent ES value in China based on Xie’s table was adjusted by calculating the priority index and the spatial difference index, and then the adjusted value was applied to obtain the spatial distribution of the comprehensive ES value in Hangzhou. On this basis, the high-level spatial agglomeration area with the highest comprehensive ES value was extracted as a hub using Getis-Ord Gi∗ hotspot analysis, while the accumulated channel with the lowest cost of comprehensive ES value was generated as a corridor through the minimum cumulative resistance (MCR) model. Both the established GI network and its buffer were delineated as the GI conservation area, which further supported the revision of the construction area in the Hangzhou Urban Master Plan (2020–2040), which was formulated by urban development policy to coordinate the conflicts between rapid urbanization and ecological protection. This study provides a characteristic example of how to establish GI networks based on ES evaluations and provides a strong reference for land-use and environmental planning in other developing countries and regions that are exposed to severe ecological deterioration. It also proves that GI network identification is not only applicable to ecological security safeguards but can also be regarded as a useful tool for containing rapid urban sprawl and outward expansion to shape and promote a sustainable urban growth pattern.