City-Level Decoupling-Full Report

City-Level Decoupling: Urban resource flows and the governance of infrastructure transitions

Figure 2.2 Two aspects of decoupling 11 Figure 2.4 Stylised reprentation of resource decoupling and impact decoupling

Human well-being Economic activity (GDP)

Resource decoupling

Resource use

Impact decoupling

Time

Environmental impact

Sorce: (UNEP, 2011a)

Source: UNEP 2011

Integral to studies of urban metabolism is an analysis of stocks and flows. Stocks include the resources available within the city (buildings, roads, infrastructures), whereas flows involve resource inputs from within and outside the city and outputs from the city to areas within and beyond its borders. 16 Haberl and colleagues refer to the build-up of ’socio-economic stocks' within the city, consisting of material stocks (e.g. buildings and infrastructural systems) and the resources that go into maintaining and using these stocks (e.g. energy and water). Studying the patterns of matter and bayabasenergy moving through cities is critical in finding solutions to optimise

need for absolute resource reduction in developed economies and relative decoupling in developing economies, the actual pace of change would be determined by the level of investment in innovation for decoupling along the entire value chain. 12

2.3 Urban flows and infrastructure

The best way to understand how cities can provide a context where various catalysts for decoupling emerge and thrive is to view them in terms of the flows of resources that pass through them. Cities are complex networks of interlocked infrastructures that have been built over many years to manipulate vast and varied flows of resources that they require to support of human prosperity. Ravetz likens the city to a living organism, describing the continuous flow of inputs and outputs as its 'metabolism'. 13 Similarly, Girardet likens the city to a ’superorganism' with roads, railways and watercourses for veins, food markets for stomachs, and waste dumps for digestion systems. 14 Studying the patterns of matter and energy moving through cities is critical for finding solutions to optimise them in the pursuit of sustainable resource management, 15 and is an important starting point for identifying opportunities for decoupling.

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