How Can Material Stock Studies Assist the Implementation of the Circular Economy in Cities?

City and regional
planners have recently started exploring a circular
approach to urban development. Meanwhile, industrial ecologists have
been designing and refining methodologies to quantify and locate material
flows and stocks within systems. This Perspective explores to which
extent material stock studies can contribute to urban circularity,
focusing on the built environment. We conducted a critical literature
review of material stock studies that claim they contribute to circular
cities. We classified each article according to a matrix we developed
leveraging existing circular built environment frameworks of urban
planning, architecture, and civil engineering and included the terminology
of material stock studies. We found that, out of 271 studies, only
132 provided information that could be relevant to the implementation
of circular cities, albeit to vastly different degrees of effectiveness.
Of these 132, only 26 reported their results in a spatially explicit
manner, which is fundamental to the effective actuation of circular
city strategies. We argue that future research should strive to provide
spatial data, avoid being siloed, and increase engagement with other
sociopolitical fields to address the different needs of the relevant
stakeholders for urban circularity.