Identifying and classifying, quantifying and visualizing green infrastructure via urban transects in Rome, Italy and Sydney, Australia

Green Infrastructure is increasingly recognised as an approach to deliver a wide-ranging set of ecosystem services in cities and to operationalize concepts of urban resilience through the better delivery of urban planning, water sensitive urban design and a broad diversity of open space types. This paper argues that the first step in the delivery of effective Green Infrastructure planning and hence ecosystem services is the identification, visualisation and calculus of the full spectrum of existing open space types within urban contexts. To test this idea two case study cities – Rome and Sydney – were selected for their differing geographical origins and planning history. In each city an analysis of the urban fabric through a novel transect mapping process revealed a range of Green Infrastructure types including a diversity of open space, public parks and plazas, streetscapes, greenways and terrain vague. This began by analysing and comparing identified land-uses with existing planning rules, strategies and mechanisms within each city. Through this process we found that for each city significant differences were evident between the formally recognised urban open space and a range of potential additional Green Infrastructure candidates were identified. We then considered the potential recognition and activation of these spaces as critical pieces of overlooked Green Infrastructure into the metrics of a sustainable future city. Comparing these two cities against each other also confirmed the richness of Green Infrastructure types globally across both expanding and contracting cities and highlights differences in data precision, land policy, governance, nomenclature and urban conditions. This research posits that in the absence of the holistic and multi-faceted understanding, metrification and the visualisation of the diversity and distribution of green infrastructure in all its forms then progress towards implementation of robust and resilient cities and their urban ecosystem services will be limited.