Using an improved 3SFCA method to assess inequities associated with multimodal accessibility to green spaces based on mismatches between supply and demand in the metropolitan of Shanghai, China

The problem that limited green spaces do not meet the increasingly demands of people living in urbanized areas is a global concerning. This study employed an improved 3SFCA method to estimate urban green space accessibility (UGSA) for residents in Shanghai based on walking, cycling, driving and public transport travel modes. It also integrated the Gini index and multiple spatial autocorrelations to evaluate the inequity and spatial disparity associated with UGSA from demand, supply and demand-supply-relationship aspects. An importance-performance analysis was conducted to identify improvement priorities for communities. The findings showed that UGSA in Shanghai was clearly unequal. Higher speed travel modes, such as driving, led to better and more equal UGSA than lower speed modes, such as walking. Old towns were generally more equal than built-up districts. The communities with worse and better UGSA supply results were mainly located in and out of the central city areas, respectively. The population demand index showed that communities with a high-supply-low-demand UGSA mismatch and a high-supply-high-demand UGSA match were in urgent and sub-urgent need of UGSA improvements, respectively, and that they were mainly clustered in the central city area. These clusters were very different to the results based on the population variable.