Assessing Fine-Scale Urban Green and Blue Infrastructure Change in Manchester, UK: A Spatiotemporal Analysis Framework to Support Environmental Land Use Management

Understanding changes in urban green and blue infrastructure (UGBI) associated with land use management can inform planners on trends in environmental change that may impact urban resilience. While UGBI change resulting from land use conversion has received significant research interest, UGBI change within otherwise consistent land uses has received scant attention. This study developed a high-resolution spatiotemporal analysis framework to map fine-scale UGBI change across all land use classes in Manchester, UK, over a period (2000–2017) of significant population growth. The study found that UGBI declined in 17 out of 29 land use classes, with an overall city-wide UGBI loss of 11.9%, compared to UGBI gains for 6.4% of the city. Declines were most concerning in residential areas, which cover 33.6% of Manchester, as UGBI in these areas is important for delivering ecosystem services to citizens. Extrapolation of change rates indicate that two-thirds of future UGBI loss could occur in residential areas. These results provide insights into socio-economic processes which are likely to have similar implications for UGBI trends in other urban areas. Such knowledge is critical to inform land use planning and management to identify where UGBI is at risk and implement appropriate policies to reverse or minimise losses.