Ecological network, ecosystem services, and green infrastructure planning: a method for the Metropolitan City of Cagliari, Italy

Human settlements exert relevant pressures over contemporary landscapes, which are progressively fragmented and threatened. Fragile landscapes are vulnerable to external shocks, such as natural disasters, flooding, and other similar events that happen more frequently, because of the changes of climate conditions. Green infrastructures, a generalization of the ecological networks, can be conceived as ensembles of artificially and naturally shaped green areas able to deliver ecosystem services to local societies, in terms of series of benefit delivered to local communities. Green infrastructures counter act landscape fragmentation through reconnecting the isolated patches back towards a system which is more resilient than before. This is a major explanation of why the integration of green infrastructure in landscape planning is at the edge of innovation in planning theory and practice. In this paper, we aim at discussing the theoretical cornerstones underlying spatial network issues of green infrastructure analysis and planning and presenting a methodology based on the assessment of the efficiency of a green infrastructure for the Metropolitan City of Cagliari, Italy. Efficiency is measured, according to the capacity to deliver ecosystem services able to increase the resilience of local landscapes in the perspective of a higher ability to adapt to climate changes. Results demonstrate a very good viability of the method and a remarkable efficiency of the GI selected for the Metropolitan City of Cagliari.