Effects of Blue-Green Infrastructures on carbon sequestration and the supply of other ecosystem services in Delta cities

Carbon sequestration is highly influenced by urban morphology, spatial distribution, and structure on a city scale due to ecological functional connectivity (Khan, 2016; Saura et al., 2011). This is especially important for delta cities, which are vulnerable to climate change. These kinds of cities are always densely occupied with man-made structures such as canals and dykes, as well as well-networked rivers, lakes and ponds, with unique hydrological and topographic conditions that form the basis of a robust and productive green–blue canvas. However, the existing landscape is under severe pressure from rapid urbanisation, and the overall ecological networks are fragmented (Yan Wang et al., 2021), which makes it harder to fulfil the real carbon benefit of urban BGI. The question of how urban BGI affects carbon benefits can be conceptualised as a synergistic response between ecological functional connectivity and carbon sequestration effects (CSE). In this light, this research will take Rotterdam and Hangzhou as case studies, analysing the landscape pattern of its BGI network and quantifying its existing urban carbon sinks with GIS and FRAGSTATS analysis. What’s more, calculation of the structural coefficients using regression and correlation analysis will determine which parameters are correlated with CSE. More importantly, this study will enable a more appropriate urban landscape structure to be proposed to achieve emission reductions as well as other regulating services for delta cities and inform BGI network planning for other cities around the world.