Sustainability, Urban Expansion, and Renaturalization

Abstract

The intensification of natural habitat degradation and the consequent loss of biodiversity represent central challenges to environmental sustainability on a global scale. Rapid urban expansion, combined with the unsustainable use of resources and the fragmentation of ecosystems, has exacerbated an unprecedented state of ecological vulnerability. Urban areas, as dynamic centers of consumption, innovation, and territorial transformation, occupy a strategic position in reversing these trends. Urban renaturalization, particularly through the adoption of Nature-Based Solutions (NBS), emerges as a diverse and evolving tool within urban planning frameworks aimed at climate resilience and ecological restoration.

Instruments such as the Municipal Ecological Structure already incorporate, in alignment with the specificities of the urban territory, tools such as ecological corridors, green infrastructure, sustainable drainage systems, and the rehabilitation of water bodies. These approaches simultaneously promote biodiversity conser

vation, population well-being, and urban environmental quality. However, the implementation and further development of such tools — or others of a similar nature — remain constrained by institutional barriers, the complexity of multi-level governance regimes, budgetary limitations, and political-cultural resistance.

This study offers a critical reflection on these challenges, exploring operational pathways to overcome them, with an emphasis on the importance of collaborative governance, informed citizen participation, and the strengthening of legal and financial frameworks. Ultimately, the work argues for the centrality of NBS as a structuring axis of contemporary urban agendas and a promising vector for the renaturalization of cities.