A definition for circular bio-based cities based on a reductionist metabolic approach

Abstract

The 2020 coronavirus pandemic demonstrated that moderation in living and consumption styles can contribute towards a more environmentally sustainable and resilient future. However, such restrained lifestyles are associated with the risk of global economic stagnation. Transitioning from linear to circular economy can potentially provide a framework to decouple environmental benefits from economic stasis. Circular cities are placed in the centre of such efforts to cradle and nurture humanity’s shift towards a sustainable future. However, we investigated the current state of circular cities around the world finding that a bio-based focus is not always prioritised. The lack of emphasis on bio-based solutions could lead to missed economic and environmental opportunities. A symbiosis between “circular”, “regenerative” and “bio-based” is here proposed as the foundation for sustainable societies transitioning to circularity. This Short Communication discusses the vision of circular bio-based cities and proposes a definition based on a reductionist metabolic approach. The aim is to set the basis for an international dialogue on urban development models capable of delivering both human and environmental prosperity beyond the reuse, refurbish and recycle concepts, and towards fully integrated regenerative urban systems which foster symbiotic relationships between urban communities and the natural ecosystem.