Proposal of a GIS-based model to assess greenspace accessibility in the Metropolitan Area of Santiago, Chile

Abstract

The study uses the ‘two-step floating catchment area’ (2SFCA) model based on network analysis to quantify the accessibility of urban greenspaces in Santiago from the perspective of urban residents. This method provides a comprehensive and consistent accessibility measure, expressing the spatial relationship between the greenspace supply, and demand from the city’s residents, in m2 of greenspace per person.

Results show that 1 in 10 people in Santiago (over 580,000 inhabitants) do not have any accessible greenspaces based on the threshold distances proposed by the Ministry of Housing and Urbanism. The model mapping presented in this study suggests that the outskirts of Santiago are more disadvantaged regarding their greenspace provision compared to central areas, with the first two quintiles of accessibility (up to 1.9 m2/person) mostly concentrated at the Southern part of the city. Santiago’s municipalities also depict a segregated spatial trend of greenspace accessibility; all cases above the metropolitan average of 4.12 m2/person are clustered towards the Northeast, whilst the rest are typically located in pericentral and peripheric areas.

Recent investments made by the Ministry of Housing showed to have improved the accessibility in some of the most greenspace-deprived areas of the city, being Cerro Navia and Pudahuel the municipalities with the highest accessibility increase of 0.83 m2/person and 0.82 m2/person respectively. This model mapping can be further used to identify specific areas of the city (at a fine census tract scale) that should be prioritised for future greenspace investment.