City-Level Decoupling-Full Report

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Paris are quite different because the common understanding of DMC is misleading when applied to cities. When the large bulk of solid waste is exported and exports are quite high, a low domestic material consumption per capita (DMC/cap) will result. This is obviously misleading. In the case of Paris for example, DMC is 2.2 t per capita, but all of the waste treatment facilities (both solid and liquid) are located outside the city. With the classic method, the related flows would be considered as exports, even if these flows are mostly flows to nature resulting from urban consumption. It seems more accurate, when calculating DMC, to consider exports minus exported wastes: for Paris the result becomes 5 t per capita. In order to avoid double counting and to give coherence to the MFA, it is then necessary to take into account DMI minus imported wastes (i.e. coming from outside the city, possibly to benefit from treatment facilities located within the city), even if they often equal zero in dense urban areas. The resulting DMC is called DMC (corrected).

where mobility is dominated by the private automobile will be very different to the DMI/ capita in cities that have an excellent public transport system. Similarly, cities with a large manufacturing base will have a DMO that includes a much higher proportion of exports than a city dominated by the services sector. Likewise, a city that is going through a phase of extensive investment in new infrastructures (urban regeneration) will have a much higher proportion of domestic material output per capita (DMO/cap) remaining fixed in NAS than a mature city where on average growth in NAS could be as low as 1 per cent per annum. Barles applied this approach to three scales of Paris: the core city of Paris itself (2.2 million people); Paris plus its surrounding suburbs (6.3 million people); and Paris, its suburbs plus the surrounding region (known as the Ile-de- France region) with 11.2 million people.

The results are reflected in Table 4.2. Note that the DMC and 'DMC (corrected)' for core

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