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1.5.2.1. Urban metabolism
Urban metabolism refers to the total sum of technical and socio-economic processes that
occur within cities, including growth, energy production, and waste disposal (Kennedy et al.,
2007, 2011). Comparable to a living organism's metabolism (ecosystems), urban metabolism
analysis (UMA) implies investigating the "city" system as a living system governed by input and
output flows, whereby the incoming flow reflects the supply of materials (natural resources)
and energy, and the outlet flow reflects the production and waste resulting from the
production processes (Guyonnaud, 2009). Wolman (1965), a leading pioneer, explicitly
described urban metabolism and applied the laws of thermodynamics in his article
"Metabolism of cities," which he described as the materials and commodities needed to
support the city's residents in the various environments they occupy (Wolman, 1965).
Therefore, the UMA investigates resource users' lifestyles and consumption patterns through
associated goods and services (Di Nardo, 2016). In addition, it provides an understanding of
such a complex system as a city by considering specific components, including economic
activities (Wolman, 1965; Kennedy et al., 2007, 2011; Bancheva, 2014). UMAs operate within
an accounting framework and have been integrated into several fields, including ecological
accounting and urban ecology (Bancheva, 2014; Movahedi & Derrible, 2021). Consequently,
and in line with sustainable development objectives, particularly those targeting climate
change mitigation and, thus, GHGs (CO2), UMA analysis is often used to identify activities or
processes that emit the most CO2 (Derrible et al., 2021). Hence, it can be associated with
analysis to improve environmental impact assessment, namely life cycle analysis (LCA), such
as transportation, water, and electricity LCA (Goldstein et al., 2013; Moore, 2013; Butt et al.,
2018; Maranghi et al., 2020; Butt et al., 2020). Indeed, associating the LCA with UMA enables
an assessment of the sustainability of an urban system (Maranghi et al., 2020). Figure 3 bellow
depicts for the "dwelling" system the overall input flows of material (construction materials),
energy (industry and conditioning), land use, and output flows (greenhouse gas production).
1.5.2.1. Urban metabolism
Urban metabolism refers to the total sum of technical and socio-economic processes that
occur within cities, including growth, energy production, and waste disposal (Kennedy et al.,
2007, 2011). Comparable to a living organism's metabolism (ecosystems), urban metabolism
analysis (UMA) implies investigating the "city" system as a living system governed by input and
output flows, whereby the incoming flow reflects the supply of materials (natural resources)
and energy, and the outlet flow reflects the production and waste resulting from the
production processes (Guyonnaud, 2009). Wolman (1965), a leading pioneer, explicitly
described urban metabolism and applied the laws of thermodynamics in his article
"Metabolism of cities," which he described as the materials and commodities needed to
support the city's residents in the various environments they occupy (Wolman, 1965).
Therefore, the UMA investigates resource users' lifestyles and consumption patterns through
associated goods and services (Di Nardo, 2016). In addition, it provides an understanding of
such a complex system as a city by considering specific components, including economic
activities (Wolman, 1965; Kennedy et al., 2007, 2011; Bancheva, 2014). UMAs operate within
an accounting framework and have been integrated into several fields, including ecological
accounting and urban ecology (Bancheva, 2014; Movahedi & Derrible, 2021). Consequently,
and in line with sustainable development objectives, particularly those targeting climate
change mitigation and, thus, GHGs (CO2), UMA analysis is often used to identify activities or
processes that emit the most CO2 (Derrible et al., 2021). Hence, it can be associated with
analysis to improve environmental impact assessment, namely life cycle analysis (LCA), such
as transportation, water, and electricity LCA (Goldstein et al., 2013; Moore, 2013; Butt et al.,
2018; Maranghi et al., 2020; Butt et al., 2020). Indeed, associating the LCA with UMA enables
an assessment of the sustainability of an urban system (Maranghi et al., 2020). Figure 3 bellow
depicts for the "dwelling" system the overall input flows of material (construction materials),
energy (industry and conditioning), land use, and output flows (greenhouse gas production).