Ecological Indicators (Jul 2021)
Taking one step further – Advancing the measurement of green and blue area accessibility using spatial network analysis
Abstract
Accessibility to green and blue areas (GBA) is one of the crucial factors in complex human-environmental systems, particularly in cities. Their quantification and mapping helps planners to reduce uncertainties in providing equal access to GBA or detect mismatches between supply and demand. Although a variety of GIS methods has been used, less attention has been paid to the pitfalls, merits, and potential of the way GBA accessibility is conceptualized and measured. This paper seeks to uncover differences between methods used for measuring two ways of conceptualizing GBA accessibility: provision and population pressure. Building on the trade-offs of these methods, this study suggests network characteristics as an approach to combine the two perspectives, and discuss the relevance of all methods for spatial planning.Network analysis can be well applied for measuring provision while buffer analysis is a good proxy for population pressure. Being of advantage compared to the polygon generation of network and buffer analysis, distance-decay analysis reports good results for both provision and population pressure. The paper demonstrates that all three methods have potentials which can be included for advancing the measurement of GBA accessibility using network characteristics. Measuring the complexity of the network and the connectivity of its nodes allows us to systematically combine provision and pressure perspectives that are relevant for planning. In particular, the suggested Local Significance in combination with the Detour Index are flexible and powerful proxies for connecting edges indicating how well people can actually walk along these routes and how spatial barriers might constrain this potential flow along service connecting areas. Using network characteristics for a proper monitoring of GBA accessibility emphasized the walkable environment surrounding GBA areas and resident’s homes what is even more challenging in ever growing and densifying urban environments.
