Thesis defense - Martial VIALLEIX

Urban Planning Put to the Test of Territorial Metabolism

Martial Vialleix (Université Paris 1 Panthéon-Sorbonne / Géographie-cités) will defend his doctoral dissertation, entitled “Urban Planning Put to the Test of Territorial Metabolism”, conducted under the supervision of Sabine Barles (Université Paris 1 Panthéon-Sorbonne / Géographie-cités), on

18 December 2025
2:00 p.m.
Centre des colloques
Room 100
Campus Condorcet
Place du Front Populaire
93300 Aubervilliers

Jury

Sabine Barles, Professor, Université Paris 1 Panthéon-Sorbonne – Dissertation Supervisor
Jean-Baptiste Bahers, CNRS Research Fellow – Reviewer
Natacha Gondran, Professor, Mines Saint-Étienne – Reviewer
Xavier Desjardins, Professor, Sorbonne Université – Examiner
Franck Aggeri, Professor, École des Mines Paris – PSL – Examiner
Christian Thibault, Department Director, Institut Paris Region – Guest Member

Abstract

Material issues (materials, waste, energy, etc.) have long been overlooked in urban planning theories and practices, which continue to strive for greater consideration of ecological issues. This thesis aims to better understand how territorial planning and operational urban planning can address these issues through the lens of the territorial metabolism approach. At the crossroads of territorial ecology and urban research, the thesis was carried out as part of a salaried position in an urban planning agency whose purpose is to develop studies and strategies for the circular economy and environmental planning. In this sense, it is strongly rooted in action, which it uses to support a two-tiered approach.

It offers an analysis of metabolism studies in France and how they fit into regional public policy. It also conducts a qualitative investigation of the development strategy of an intermunicipal community in Greater Paris (Est Ensemble) in which material issues have been introduced. The results contribute not only to research on and around territorial metabolism; but also to urban research studying the greening of development; and to the territorialization of the circular economy as a subject of public policy. The consideration of material issues in territorial and urban policies is progressing, both in urban planning instruments and in the implementation of territorial strategies and operational approaches aimed at reducing, reusing, or recycling materials. However, this progress is still tentative. It faces numerous obstacles (financial, technical, organizational, etc.), while many contradictions are at work, preventing the emergence of comprehensive, inter-territorial urban planning action capable of dematerializing metabolism.