The biogeochemical imprint of human metabolism in Paris Megacity: A regionalized analysis of a water-agro-food system

Fabien Esculier (1, 2) , Julia Le Noë (2) , Sabine Barles (3) , Gilles Billen (2) , Benjamin Créno (4) , Josette Garnier (2) , Jacques Lesavre (5) , Léo Petit (2) , Jean-Pierre Tabuchi (6)

1 LEESU - Laboratoire Eau Environnement et Systèmes Urbains
2 METIS - Milieux Environnementaux, Transferts et Interactions dans les hydrosystèmes et les Sols
3 GC (UMR_8504) - Géographie-cités
4 ENPC - École des Ponts ParisTech
5 Agence de l'Eau Seine-Normandie
6 SIAAP - Direction Santé et Environnement

Megacities are facing a twofold challenge regarding resources: (i) ensure their availability for a growing urban population and (ii) limit the impact of resource losses to the environment. This paper focuses on two essential resources – nitrogen and phosphorus – and challenges their sustainable management in the water-agro-food system of Paris Megacity. An in-depth analysis of the nitrogen and phosphorus imprint of Paris Megacity was conducted, originally centered on human metabolism through consumption and excretion of these two elements. Upstream, the whole agricultural production that feeds Paris Megacity was scrutinized and nitrogen and phosphorus flows in the agro-system were fully documented. Downstream, the analysis of solid waste and wastewater management in Paris Megacity showed the fate of nitrogen and phosphorus imported into the city.

Mots clés: Biogeochemical imprint; Water-agro-food system; Urban metabolism; Megacity; Nitrogen cycle; Phosphorus cycle

Mots clés: ACL; CRIA

Domaines: Sciences de l'Homme et Société; Etudes de l'environnement; Hydrologie; Biodiversité et Ecologie

Fabien Esculier, Julia Le Noë, Sabine Barles, Gilles Billen, Benjamin Créno, et al.. The biogeochemical imprint of human metabolism in Paris Megacity: A regionalized analysis of a water-agro-food system. Journal of Hydrology, 2018, 573, ⟨10.1016/j.jhydrol.2018.02.043⟩. ⟨hal-01821635⟩